National Library of Energy BETA

Sample records for benzene toluene ethylbenzene

  1. Mobility of Supercooled liquid Toluene, Ethylbenzene, and Benzene...

    Office of Scientific and Technical Information (OSTI)

    and Benzene near their Glass Transition Temperatures Investigated using Inert Gas Permeation Citation Details In-Document Search Title: Mobility of Supercooled liquid...

  2. Mobility of Supercooled liquid Toluene, Ethylbenzene, and Benzene near their Glass Transition Temperatures Investigated using Inert Gas Permeation

    SciTech Connect (OSTI)

    May, Robert A.; Smith, R. Scott; Kay, Bruce D.

    2013-11-21

    We investigate the mobility of supercooled liquid toluene, ethylbenzene, and benzene near their respective glass transition temperatures (Tg). The permeation rate of Ar, Kr, and Xe through the supercooled liquid created when initially amorphous overlayers heated above their glass transition temperature is used to determine the diffusivity. Amorphous benzene crystallizes at temperatures well below its Tg and as a result the inert gas underlayer remains trapped until the onset of benzene desorption. In contrast, for toluene and ethylbenzene the onset of inert gas permeation is observed at temperatues near Tg. The inert gas desorption peak temperature as a function of the heating rate and overlayer thickness is used to quantify the diffusivity of supercooled liquid toluene and ethylbenzene from 115 K to 135 K. In this temperature range, diffusivities are found to vary across five orders of magnitude (~10-14 to 10-9 cm2/s). These data are compared to viscosity measurements and used to determine the low temperature fractional Stokes-Einstein exponent. Efforts to determine the diffusivity of a mixture of benzene and ethylbenzene are detailed, and the effect of mixing these materials on benzene crystallization is explored using infrared spectroscopy.

  3. Headspace solid-phase microextraction (HS-SPME) for the determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) in foundry molding sand

    SciTech Connect (OSTI)

    Dungan, R.S. [USDA ARS, Beltsville, MD (United States). Environmental Management & Byproducts Utilization Laboratory

    2005-07-01

    The use of headspace solid-phase microextraction (HS-SPME) to determine benzene, toluene, ethylbenzene, and xylenes (BTEX) in foundry molding sand, specifically a 'green sand' (clay-bonded sand) was investigated. The BTEX extraction was conducted using a 75 {mu} M carboxen-polydimethylsiloxane (CAR-PDMS) fiber, which was suspended above 10 g of sample. The SPME fiber was desorbed in a gas chromatograph injector port (280{sup o}C for 1 min) and the analytes were characterized by mass spectrometry. The effects of extraction time and temperature, water content, and clay and bituminous coal percentage on HS-SPME of BTEX were investigated. Because green sands contain bentonite clay and carbonaceous material such as crushed bituminous coal, a matrix effect was observed. The detection limits for BTEX were determined to be {lt}= 0.18 ng g{sup -1} of green sand.

  4. Solubilities of Toluene, Benzene and TCE in High-Biomass Systems

    SciTech Connect (OSTI)

    Barton, John W.; Vodraska, Christopher D; Flanary, Sandie A.; Davison, Brian H

    2008-01-01

    We report measurements of solubility limits for benzene, toluene, and TCE in systems that contain varying levels of biomass up to 0.13 g/mL. The solubility limit increased from 20 to 48 mM when biomass (in the form of yeast) was added to aqueous batch systems containing benzene. The toluene solubility limit increased from 4.9 to greater than 20 mM. For TCE, the solubility increased from 8 mM to more than 1000 mM. Solubility for TCE was most heavily impacted by biomass levels, changing by two orders of magnitude.

  5. Reactions of the CN Radical with Benzene and Toluene: Product Detection and Low-Temperature Kinetics

    SciTech Connect (OSTI)

    Trevitt, Adam J.; Goulay, Fabien; Taatjes, Craig A.; Osborn, David L.; Leone, Stephen R.

    2009-12-23

    Low temperature rate coefficients are measured for the CN + benzene and CN + toluene reactions using the pulsed Laval nozzle expansion technique coupled with laser-induced fluorescence detection. The CN + benzene reaction rate coefficient at 105, 165 and 295 K is found to be relatively constant over this temperature range, 3.9 - 4.9 x 10-10 cm3 molecule-1 s-1. These rapid kinetics, along with the observed negligible temperature dependence, are consistent with a barrierless reaction entrance channel and reaction efficiencies approaching unity. The CN + toluene reaction is measured to have a slower rate coefficient of 1.3 x 10-10 cm3 molecule-1 s-1 at 105 K. At room temperature, non-exponential decay profiles are observed for this reaction that may suggest significant back-dissociation of intermediate complexes. In separate experiments, the products of these reactions are probed at room temperature using synchrotron VUV photoionization mass spectrometry. For CN + benzene, cyanobenzene (C6H5CN) is the only product recorded with no detectable evidence for a C6H5 + HCN product channel. In the case of CN + toluene, cyanotoluene (NCC6H4CH3) constitutes the only detected product. It is not possible to differentiate among the ortho, meta and para isomers of cyanotoluene because of their similar ionization energies and the ~;; 40 meV photon energy resolution of the experiment. There is no significant detection of benzyl radicals (C6H5CH2) that would suggest a H-abstraction or a HCN elimination channel is prominent at these conditions. As both reactions are measured to be rapid at 105 K, appearing to have barrierless entrance channels, it follows that they will proceed efficiently at the temperatures of Saturn?s moon Titan (~;;100 K) and are also likely to proceed at the temperature of interstellar clouds (10-20 K).

  6. Genotoxicity and apoptosis in Drosophila melanogaster exposed to benzene, toluene and xylene: Attenuation by quercetin and curcumin

    SciTech Connect (OSTI)

    Singh, Mahendra P.; Mishra, M.; Sharma, A.; Shukla, A.K.; Mudiam, M.K.R.; Patel, D.K.; Ram, K. Ravi; Chowdhuri, D. Kar

    2011-05-15

    Monocyclic aromatic hydrocarbons (MAHs) such as benzene, toluene and xylene are being extensively used for various industrial and household purposes. Exposure to these hydrocarbons, occupationally or non-occupationally, is harmful to organisms including human. Several studies tested for toxicity of benzene, toluene and xylene, and interestingly, only a few studies looked into the attenuation. We used Drosophila model to test the genotoxic and apoptotic potential of these compounds and subsequently evaluated the efficiency of two phytochemicals, namely, quercetin and curcumin in attenuating test chemical induced toxicity. We exposed third instar larvae of wild type Drosophila melanogaster (Oregon R{sup +}) to 1.0-100.0 mM benzene, toluene or xylene, individually, for 12, 24 and 48 h and examined their apoptotic and genotoxic potential. We observed significantly (P < 0.001) increased apoptotic markers and genotoxicity in a concentration- and time-dependent manner in organisms exposed to benzene, toluene or xylene. We also observed significantly (P < 0.001) increased cytochrome P450 activity in larvae exposed to test chemicals and this was significantly reduced in the presence of 3',4'-dimethoxyflavone, a known Aryl hydrocarbon receptor (AhR) blocker. Interestingly, we observed a significant reduction in cytochrome P450 activity, GST levels, oxidative stress parameters, genotoxic and apoptotic endpoints when organisms were exposed simultaneously to test chemical along with quercetin or curcumin. The study further suggests the suitability of D. melanogaster as an alternate animal model for toxicological studies involving benzene, toluene and xylene and its potential in studying the protective role(s) of phytochemicals.

  7. Toluene pyrolysis studies and high temperature reactions of propargyl chloride

    SciTech Connect (OSTI)

    Kern, R.D.; Chen, H.; Qin, Z.

    1993-12-01

    The main focus of this program is to investigate the thermal decompositions of fuels that play an important role in the pre-particle soot formation process. It has been demonstrated that the condition of maximum soot yield is established when the reaction conditions of temperature and pressure are sufficient to establish a radical pool to support the production of polyaromatic hydrocarbon species and the subsequent formation of soot particles. However, elevated temperatures result in lower soot yields which are attributed to thermolyses of aromatic ring structures and result in the bell-shaped dependence of soot yield on temperature. The authors have selected several acyclic hydrocarbons to evaluate the chemical thermodynamic and kinetic effects attendant to benzene formation. To assess the thermal stability of the aromatic ring, the authors have studied the pyrolyses of benzene, toluene, ethylbenzene, chlorobenzene and pyridine. Time-of-flight mass spectrometry (TOF) is employed to analyze the reaction zone behind reflected shock waves. Reaction time histories of the reactants, products, and intermediates are constructed and mechanisms are formulated to model the experimental data. The TOF work is often performed with use of laser schlieren densitometry (LS) to measure density gradients resulting from the heats of various reactions involved in a particular pyrolytic system. The two techniques, TOF and LS, provide independent and complementary information about ring formation and ring rupture reactions.

  8. Polyfunctional catalyst for processiing benzene fractions

    SciTech Connect (OSTI)

    G. Byakov; B.D. Zubitskii; B.G. Tryasunov; I.Ya. Petrov

    2009-05-15

    A by-product of the coke industry is a raw benzene fraction benzene- 1 which may serve as for catalytic processes. The paper reports a study on the influence of the composition and temperatures on the activity and selectivity of NiO-V{sub 2}O{sub 6}-MoO{sub 3}/{gamma}-Al{sub 2}O{sub 3} catalysts and the corresponding binary and tertiary subsystems are studied by a pulse method in model reactions; the hydrodealkylating of toluene and the hydrodesulfurizing of thioprhene. The optimal catalyst composition is established. The new catalyst is compared with industrial catalysts.

  9. Investigation of critical equivalence ratio and chemical speciation in flames of ethylbenzene-ethanol blends

    SciTech Connect (OSTI)

    Therrien, Richard J.; Ergut, Ali; Levendis, Yiannis A.; Richter, Henning; Howard, Jack B.; Carlson, Joel B.

    2010-02-15

    This work investigates five different one-dimensional, laminar, atmospheric pressure, premixed ethanol/ethylbenzene flames (0%, 25%, 50%, 75% and 90% ethanol by weight) at their soot onset threshold ({phi}{sub critical}). Liquid ethanol/ethylbenzene mixtures were pre-vaporized in nitrogen, blended with an oxygen-nitrogen mixture and, upon ignition, burned in premixed one-dimensional flames at atmospheric pressure. The flames were controlled so that each was at its visual soot onset threshold, and all had similar temperature profiles (determined by thermocouples). Fixed gases, light volatile hydrocarbons, polycyclic aromatic hydrocarbons (PAH), and oxygenated aromatic hydrocarbons were directly sampled at three locations in each flame. The experimental results were compared with a detailed kinetic model, and the modeling results were used to perform a reaction flux analysis of key species. The critical equivalence ratio was observed to increase in a parabolic fashion as ethanol concentration increased in the fuel mixture. The experimental results showed increasing trends of methane, ethane, and ethylene with increasing concentrations of ethanol in the flames. Carbon monoxide was also seen to increase significantly with the increase of ethanol in the flame, which removes carbon from the PAH and soot formation pathways. The PAH and oxygenated aromatic hydrocarbon values were very similar in the 0%, 25% and 50% ethanol flames, but significantly lower in the 75% and 90% ethanol flames. These results were in general agreement with the model and were reflected by the model soot predictions. The model predicted similar soot profiles for the 0%, 25% and 50% ethanol flames, however it predicted significantly lower values in the 75% and 90% ethanol flames. The reaction flux analysis revealed benzyl to be a major contributor to single and double ring aromatics (i.e., benzene and naphthalene), which was identified in a similar role in nearly sooting or highly sooting ethylbenzene flames. The presence of this radical was significantly reduced as ethanol concentration was increased in the flames, and this effect in combination with the lower carbon to oxygen ratios and the enhanced formation of carbon monoxide, are likely what allowed higher equivalence ratios to be reached without forming soot. (author)

  10. Degradative capacities and bioaugmentation potential of an anaerobic benzene-degrading bacterium strain DN11

    SciTech Connect (OSTI)

    Yuki Kasai; Yumiko Kodama; Yoh Takahata; Toshihiro Hoaki; Kazuya Watanabe

    2007-09-15

    Azoarcus sp. strain DN11 is a denitrifying bacterium capable of benzene degradation under anaerobic conditions. The present study evaluated strain DN11 for its application to bioaugmentation of benzene-contaminated underground aquifers. Strain DN11 could grow on benzene, toluene, m-xylene, and benzoate as the sole carbon and energy sources under nitrate-reducing conditions, although o- and p-xylenes were transformed in the presence of toluene. Phenol was not utilized under anaerobic conditions. Kinetic analysis of anaerobic benzene degradation estimated its apparent affinity and inhibition constants to be 0.82 and 11 {mu}M, respectively. Benzene-contaminated groundwater taken from a former coal-distillation plant site in Aichi, Japan was anaerobically incubated in laboratory bottles and supplemented with either inorganic nutrients (nitrogen, phosphorus, and nitrate) alone, or the nutrients plus strain DN11, showing that benzene was significantly degraded only when DN11 was introduced. Denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments, and quantitative PCR revealed that DN11 decreased after benzene was degraded. Following the decrease in DN11 16S rRNA gene fragments corresponding to bacteria related to Owenweeksia hongkongensis and Pelotomaculum isophthalicum, appeared as strong bands, suggesting possible metabolic interactions in anaerobic benzene degradation. Results suggest that DN11 is potentially useful for degrading benzene that contaminates underground aquifers at relatively low concentrations. 50 refs., 6 figs., 1 tab.

  11. Modeling theta-theta Interactions with the Effective Fragment Potential Method: The Benzene Dimer and Substituents

    SciTech Connect (OSTI)

    Toni Smithl; Lyudmila V. Slipchenko; Mark S. Gordon

    2008-02-27

    This study compares the results of the general effective fragment potential (EFP2) method to the results of a previous combined coupled cluster with single, double, and perturbative triple excitations [CCSD(T)] and symmetry-adapted perturbation theory (SAPT) study [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690] on substituent effects in {pi}-{pi} interactions. EFP2 is found to accurately model the binding energies of the benzene-benzene, benzene-phenol, benzene-toluene, benzene-fluorobenzene, and benzene-benzonitrile dimers, as compared with high-level methods [Sinnokrot and Sherrill, J. Am. Chem. Soc., 2004, 126, 7690], but at a fraction of the computational cost of CCSD(T). In addition, an EFP-based Monte Carlo/simulated annealing study was undertaken to examine the potential energy surface of the substituted dimers.

  12. Soot precursor measurements in benzene and hexane diffusion flames

    SciTech Connect (OSTI)

    Kobayashi, Y.; Furuhata, T.; Amagai, K.; Arai, M.

    2008-08-15

    To clarify the mechanism of soot formation in diffusion flames of liquid fuels, measurements of soot and its precursors were carried out. Sooting diffusion flames formed by a small pool combustion equipment system were used for this purpose. Benzene and hexane were used as typical aromatic and paraffin fuels. A laser-induced fluorescence (LIF) method was used to obtain spatial distributions of polycyclic aromatic hydrocarbons (PAHs), which are considered as soot particles. Spatial distributions of soot in test flames were measured by a laser-induced incandescence (LII) method. Soot diameter was estimated from the temporal change of LII intensity. A region of transition from PAHs to soot was defined from the results of LIF and LII. Flame temperatures, PAH species, and soot diameters in this transition region were investigated for both benzene and hexane flames. The results show that though the flame structures of benzene and hexane were different, the temperature in the PAHs-soot transition region of the benzene flame was similar to that of the hexane flame. Furthermore, the relationship between the PAH concentrations measured by gas chromatography in both flames and the PAH distributions obtained from LIF are discussed. It was found that PAHs with smaller molecular mass, such as benzene and toluene, remained in both the PAHs-soot transition and sooting regions, and it is thought that molecules heavier than pyrene are the leading candidates for soot precursor formation. (author)

  13. Fuel Dependence of Benzene Pathways

    SciTech Connect (OSTI)

    Zhang, H; Eddings, E; Sarofim, A; Westbrook, C

    2008-07-14

    The relative importance of formation pathways for benzene, an important precursor to soot formation, was determined from the simulation of 22 premixed flames for a wide range of equivalence ratios (1.0 to 3.06), fuels (C{sub 1}-C{sub 12}), and pressures (20 to 760 torr). The maximum benzene concentrations in 15 out of these flames were well reproduced within 30% of the experimental data. Fuel structural properties were found to be critical for benzene production. Cyclohexanes and C{sub 3} and C{sub 4} fuels were found to be among the most productive in benzene formation; and long-chain normal paraffins produce the least amount of benzene. Other properties, such as equivalence ratio and combustion temperatures, were also found to be important in determining the amount of benzene produced in flames. Reaction pathways for benzene formation were examined critically in four premixed flames of structurally different fuels of acetylene, n-decane, butadiene, and cyclohexane. Reactions involving precursors, such as C{sub 3} and C{sub 4} species, were examined. Combination reactions of C{sub 3} species were identified to be the major benzene formation routes with the exception of the cyclohexane flame, in which benzene is formed exclusively from cascading fuel dehydrogenation via cyclohexene and cyclohexadiene intermediates. Acetylene addition makes a minor contribution to benzene formation, except in the butadiene flame where C{sub 4}H{sub 5} radicals are produced directly from the fuel, and in the n-decane flame where C{sub 4}H{sub 5} radicals are produced from large alkyl radical decomposition and H atom abstraction from the resulting large olefins.

  14. Collision lifetimes of polyatomic molecules at low temperatures: Benzene–benzene vs benzene–rare gas atom collisions

    SciTech Connect (OSTI)

    Cui, Jie; Krems, Roman V.; Li, Zhiying

    2014-10-28

    We use classical trajectory calculations to study the effects of the interaction strength and the geometry of rigid polyatomic molecules on the formation of long-lived collision complexes at low collision energies. We first compare the results of the calculations for collisions of benzene molecules with rare gas atoms He, Ne, Ar, Kr, and Xe. The comparison illustrates that the mean lifetimes of the collision complexes increase monotonically with the strength of the atom–molecule interaction. We then compare the results of the atom–benzene calculations with those for benzene–benzene collisions. The comparison illustrates that the mean lifetimes of the benzene–benzene collision complexes are significantly reduced due to non-ergodic effects prohibiting the molecules from sampling the entire configuration space. We find that the thermally averaged lifetimes of the benzene–benzene collisions are much shorter than those for Xe with benzene and similar to those for Ne with benzene.

  15. Process for the preparation of ethyl benzene

    DOE Patents [OSTI]

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1995-12-19

    Ethyl benzene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50 C to 300 C, using as the catalyst a mole sieve characterized as acidic by feeding ethylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene and diethyl benzene in the bottoms. The bottoms are fractionated, the ethyl benzene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diethyl benzene to ethyl benzene which is again separated and recovered. 2 figs.

  16. Process for the preparation of ethyl benzene

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1995-01-01

    Ethyl benzene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50.degree. C. to 300.degree. C., using as the catalyst a mole sieve characterized as acidic by feeding ethylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene and diethyl benzene in the bottoms. The bottoms are fractionated, the ethyl benzene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diethyl benzene to ethyl benzene which is again separated and recovered.

  17. The role of CO2 as a soft oxidant for dehydrogenation of ethylbenzene to styrene over a high-surface-area ceria catalyst

    SciTech Connect (OSTI)

    Zhang, Li; Wu, Zili; Nelson, Nicholas; Sadow, Aaron D.; Slowing, Igor I.; Overbury, Steven H.

    2015-09-22

    Catalytic performance and the nature of surface adsorbates were investigated for high-surface-area ceria during ethylbenzene oxidative dehydrogenation (ODH) reaction using CO2 as a soft oxidant. A template assisted method was used to synthesize the high-surface-area ceria. The interactions between ethylbenzene, styrene and CO2 on the surface of ceria and the role of CO2 for the ethylbenzene ODH reaction have been investigated in detail by using activity test, in situ Diffuse Reflectance Infrared and Raman spectroscopy. Not only did CO2 as an oxidant favor the higher yield of styrene, but it also inhibited the deposition of coke during the ethylbenzene ODH reaction. Ethylbenzene ODH reaction over ceria followed a two-step pathway: Ethylbenzene is first dehydrogenated to styrene with H2 formed simultaneously, and then CO2 reacts with H2 via the reverse water gas shift. The styrene produced can easily polymerize to form polystyrene, a key intermediate for coke formation. In the absence of CO2, the polystyrene transforms into graphite-like coke at temperatures above 500 °C, which leads to catalyst deactivation. While in the presence of CO2, the coke deposition can be effectively removed via oxidation with CO2.

  18. The role of CO2 as a soft oxidant for dehydrogenation of ethylbenzene to styrene over a high-surface-area ceria catalyst

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Li; Wu, Zili; Nelson, Nicholas; Sadow, Aaron D.; Slowing, Igor I.; Overbury, Steven H.

    2015-09-22

    Catalytic performance and the nature of surface adsorbates were investigated for high-surface-area ceria during ethylbenzene oxidative dehydrogenation (ODH) reaction using CO2 as a soft oxidant. A template assisted method was used to synthesize the high-surface-area ceria. The interactions between ethylbenzene, styrene and CO2 on the surface of ceria and the role of CO2 for the ethylbenzene ODH reaction have been investigated in detail by using activity test, in situ Diffuse Reflectance Infrared and Raman spectroscopy. Not only did CO2 as an oxidant favor the higher yield of styrene, but it also inhibited the deposition of coke during the ethylbenzene ODHmore » reaction. Ethylbenzene ODH reaction over ceria followed a two-step pathway: Ethylbenzene is first dehydrogenated to styrene with H2 formed simultaneously, and then CO2 reacts with H2 via the reverse water gas shift. The styrene produced can easily polymerize to form polystyrene, a key intermediate for coke formation. In the absence of CO2, the polystyrene transforms into graphite-like coke at temperatures above 500 °C, which leads to catalyst deactivation. While in the presence of CO2, the coke deposition can be effectively removed via oxidation with CO2.« less

  19. Evaluation of a Polyvinyl Toluene Neutron Counter Array (Conference...

    Office of Scientific and Technical Information (OSTI)

    Utilizing a compact array of borated Polyvinyl Toluene light pipes and Photomultiplier Tubes, pulse shape analysis, standard spectral histogramming, and multiplicity counting can ...

  20. Low level benzene exposure in Sweden: effect on blood elements and body burden of benzene

    SciTech Connect (OSTI)

    Berlin, M.

    1985-01-01

    Measurements for benzene exposure were performed for different work places. In addition, breath benzene concentrations were measured in different occupations in order to establish toxico-kinetics of benzene in man; chromosomal aberrations in lymphocytes of exposed workers were also examined. Smoking appears to result in a large increase in benzene concentration in exhaled breath. The smoke from one cigarette contains 60-80 micrograms of benzene. It was found that exposure levels of 10 ppm are rather uncommon among workers handling gasoline or gasoline equipment. It was concluded that the gasoline load of road tankers cannot be responsible for chromosome changes of the driver, as milk truck drivers showed the same changes. These results did not prove that benzene was the cause of the observed changes. Smoking is the confounding factor, with a potency of at least the same order of magnitude as benzene. In addition, our present knowledge about mechanisms of benzene is not sufficiently developed to permit quantitative conclusions as to the human health risks.

  1. Indirect validation of benzene exposure assessment by association with benzene poisoning

    SciTech Connect (OSTI)

    Dosemeci, M.; Linet, M.; Wacholder, S.

    1996-12-01

    We present a validation study of a quantitative retrospective exposure assessment method used in a follow-up study of workers exposed to benzene. Assessment of exposure to benzene was carried out in 672 factories in 12 cities in China. Historical exposure data were collected for 3179 unique job titles. The basic unit for exposure assessment was a factory/work unit/job title combination over seven periods between 1949 and 1987. A total of 18,435 exposure estimates was developed, using all available historical information, including 8477 monitoring data. Overall, 38% of the estimates were based on benzene monitoring data. The highest time-weighted average exposures were observed for the rubber industry (30.7 ppm) and for rubber glue applicators (52.6 ppm). Because of its recognized link with benzene exposure, the association between a clinical diagnosis of benzene poisoning and benzene exposure was evaluated to validate the assessment method that we used in the cohort study. Our confidence in the assessment method is supported by the observation of a strong positive trend between benzene poisoning and various measures, especially recent intensity of exposure to benzene. 23 refs., 6 figs., 2 tabs.

  2. Exposure Evaluation for Benzene, Lead and Noise in Vehicle and Equipment Repair Shops

    SciTech Connect (OSTI)

    Sweeney, Lynn C.

    2013-04-10

    An exposure assessment was performed at the equipment and vehicle maintenance repair shops operating at the U. S. Department of Energy Hanford site, in Richland, Washington. The maintenance shops repair and maintain vehicles and equipment used in support of the Hanford cleanup mission. There are three general mechanic shops and one auto body repair shop. The mechanics work on heavy equipment used in construction, cranes, commercial motor vehicles, passenger-type vehicles in addition to air compressors, generators, and farm equipment. Services include part fabrication, installation of equipment, repair and maintenance work in the engine compartment, and tire and brake services. Work performed at the auto body shop includes painting and surface preparation which involves applying body filler and sanding. 8-hour time-weighted-average samples were collected for benzene and noise exposure and task-based samples were collected for lead dust work activities involving painted metal surfaces. Benzene samples were obtained using 3Mâ„¢ 3520 sampling badges and were analyzed for additional volatile organic compounds. These compounds were selected based on material safety data sheet information for the aerosol products used by the mechanics for each day of sampling. The compounds included acetone, ethyl ether, toluene, xylene, VM&P naphtha, methyl ethyl ketone, and trichloroethylene. Laboratory data for benzene, VM&P naphtha, methyl ethyl ketone and trichloroethylene were all below the reporting detection limit. Airborne concentrations for acetone, ethyl ether, toluene and xylene were all less than 10% of their occupational exposure limit. The task-based samples obtained for lead dusts were submitted for a metal scan analysis to identify other metals that might be present. Laboratory results for lead dusts were all below the reporting detection limit and airborne concentration for the other metals observed in the samples were less than 10% of the occupational exposure limit. Noise dosimetry sampling was performed on a random basis and was representative of the different work activities within the four shops. Twenty three percent of the noise samples exceeded the occupational exposure limit of 85 decibels for an 8-hour time-weightedaverage. Work activities where noise levels were higher included use of impact wrenches and grinding wheels.

  3. Pilot-Scale Benzene Retention and Release Demonstration

    SciTech Connect (OSTI)

    Marek, J.C.

    2003-11-10

    During the initial months of In-Tank Precipitation radioactive operation in 1995 the process experienced high rates of tetraphenylborate decomposition with assumed corresponding high rates of benzene generation. In March 1996 after a two month quiescent period, a water addition to Tank 48H resulted in an unexpected benzene release to the tank vapor phase. This was the first time a low energy input resulted in a significant release rate. This led to questions about how benzene, generated in-situ by TPB decomposition, was retained in the surrounding potassium tetraphenylborate slurry. It was postulated the retention mechanism may have changed during the quiescent period prior to March so the benzene present became readily releasable to the vapor phase with low energy input to the slurry or that enough benzene accumulated that some of it was in a different, more releasable form. Readily releasable is a qualitative term defined as a rapid release of benzene at a rate approaching evaporation of a free benzene layer. It is intended to distinguish between benzene in a form with high liquid phase resistance to mass transfer diffusion controlled from benzene in a form with minimal liquid phase resistance to mass transfer free benzene layer evaporation. If a readily releasable form of benzene was present, the vapor space profile during release tests was anticipated to have an initial benzene vapor space concentration peak followed by a lower vapor concentration, longer duration release.

  4. Toluene nitration in irradiated nitric acid and nitrite solution

    SciTech Connect (OSTI)

    Gracy Elias; Bruce J. Mincher; Stephen P. Mezyk; Jim Muller; Leigh R. Martin

    2011-04-01

    The kinetics, mechanisms, and stable products produced for the aryl alkyl mild ortho-para director - toluene, in irradiated nitric acid and neutral nitrite solutions were investigated using ?, and pulse radiolysis. Electron pulse radiolysis was used to determine the bimolecular rate constants for the reaction of toluene with different transient species produced by irradiation. HPLC with UV detection was primarily used to assess the stable reaction products. GC-MS and LC-MS were used to confirm the results from HPLC. Free-radical nitration reaction products were found in irradiated acidic and neutral media. In acidic medium, the ring substitution and side chain substitution and oxidation produced different nitro products. In ring substitution, nitrogen oxide radicals were added mainly to hydroxyl radical-produced cyclohexadienyl radical, and in side chain substitution they were added to the carbon-centered benzyl radical produced by H-atom abstraction. In neutral nitrite toluene solution, radiolytic ring nitration products approached a statistically random distribution, suggesting a free-radical reaction involving addition of the •NO2 radical.

  5. Biofiltration control of VOC emissions: Butane and benzene

    SciTech Connect (OSTI)

    Allen, E.R.

    1995-12-31

    Laboratory studies were conducted on the biological elimination of n-butane and benzene from air streams using activated sludge-treated compost biofilters. Four types of experimental biofilter systems were developed: a bench scale packed tower system used primarily for kinetic studies; a small scale column system used to study the effects of different filter media on n-butane removal; a three stage system used to study benzene elimination; and a static batch biofilter system used to study the effects of temperature, compost water content, compost pH, and initial benzene concentrations on benzene elimination. Removal efficiencies greater than 90% were obtained for n-butane. Removal followed first order kinetics at inlet concentrations less than 25 ppM n-butane and zero order kinetics above 100 ppM n-butane. Removal of benzene followed fractional order kinetics for inlet concentrations from 15 to 200 ppM benzene. Thus, the removal of benzene is both mass transfer and bioreaction limited for the concentration range studied. The removal efficiency of benzene was found to be highly dependent on compost water content, compost pH, and temperature. Compost showed a low capacity for benzene removal, which suggested that degradation of these hydrocarbons required different species of microorganisms.

  6. Catalytic conversion of alcohols to hydrocarbons with low benzene content

    DOE Patents [OSTI]

    Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin

    2016-03-08

    A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.

  7. In situ BTEX biotransformation under enhanced nitrate- and sulfate-reducing conditions

    SciTech Connect (OSTI)

    Reinhard, M.; Shang, S.; Kitanidis, P.K.; Orwin, E.; Hopkins, G.D.; LeBron, C.A.

    1997-01-01

    In situ anaerobic biotransformation of BTEX (benzene, toluene, ethylbenzene, o-xylene, and m-xylene) was investigated under enhanced nitrate- and sulfate-reducing conditions. Controlled amounts of BTEX compounds added to slugs of treated groundwater were released into a gasoline-contaminated aquifer at Seal Beach, CA. In a series of studies, the slugs, 470-1700 L in volume, were released into the aquifer through a multi-port injection/extraction well and were subsequently withdrawn over a 2-3 month period. To evaluate unamended in situ conditions, the injectate was treated with granular activated carbon (GAC) and augmented with bromide as a tracer. To evaluate nitrate- and sulfate-reducing conditions, the injectate was also deionized and augmented with 200-300 {mu}g/L BTEX, nitrate or sulfate, and background electrolytes. Under unamended conditions, transformation appeared to be limited to the slow removal of toluene and m,p-xylene (i.e. sum of m+p-xylene). Under nitrate-reducing conditions, toluene, ethylbenzene, and m-xylene were transformed without a lag phase in less than 10 days, and o-xylene was transformed in 72 days. Under sulfate-reducing conditions, toluene, m-xylene and o-xylene were completely transformed in less then 50 days, and ethylbenzene was removed in 60 days. Benzene appeared to be removed under sulfate-reducing conditions, but the trend was pronounced only at some levels. 47 refs., 11 figs., 2 tabs.

  8. Products of the Benzene + O(3P) Reaction

    SciTech Connect (OSTI)

    Taatjes, Craig A.; Osborn, David L.; Selby, Talitha M.; Meloni, Giovanni; Trevitt, Adam J.; Epifanovsky, Evgeny; Krylov, Anna I.; Sirjean, Baptiste; Dames, Enoch; Wang, Hai

    2009-12-21

    The gas-phase reaction of benzene with O(3P) is of considerable interest for modeling of aromatic oxidation, and also because there exist fundamental questions concerning the prominence of intersystem crossing in the reaction. While its overall rate constant has been studied extensively, there are still significant uncertainties in the product distribution. The reaction proceeds mainly through the addition of the O atom to benzene, forming an initial triplet diradical adduct, which can either dissociate to form the phenoxy radical and H atom, or undergo intersystem crossing onto a singlet surface, followed by a multiplicity of internal isomerizations, leading to several possible reaction products. In this work, we examined the product branching ratios of the reaction between benzene and O(3P) over the temperature range of 300 to 1000 K and pressure range of 1 to 10 Torr. The reactions were initiated by pulsed-laser photolysis of NO2 in the presence of benzene and helium buffer in a slow-flow reactor, and reaction products were identified by using the multiplexed chemical kinetics photoionization mass spectrometer operating at the Advanced Light Source (ALS) of Lawrence Berkeley National Laboratory. Phenol and phenoxy radical were detected and quantified. Cyclopentadiene and cyclopentadienyl radical were directly identified for the first time. Finally, ab initio calculations and master equation/RRKM modeling were used to reproduce the experimental branching ratios, yielding pressure-dependent rate expressions for the reaction channels, including phenoxy + H, phenol, cyclopentadiene + CO, which are proposed for kinetic modeling of benzene oxidation.

  9. Effect of ozonation on the composition of crude coal-tar benzene

    SciTech Connect (OSTI)

    Semenova, S.A.; Patrakov, Y.F.

    2007-05-15

    The effect of ozonation on the composition of crude benzene produced by the coal-tar chemical industry was studied.

  10. New packing in absorption systems for trapping benzene from coke-oven gas

    SciTech Connect (OSTI)

    V.V. Grabko; V.M. Li; T.A. Shevchenko; M.A. Solov'ev

    2009-07-15

    The efficiency of benzene removal from coke-oven gas in absorption units OAO Alchevskkoks with new packing is assessed.

  11. Molecular dynamics simulations of the effects of salts on the aggregation properties of benzene in water.

    SciTech Connect (OSTI)

    Smith, P. E.

    2003-07-16

    The specific aims of the project were: to provide an atomic level description of the interactions between benzene, water and ions in solutions. To determine the degree of association between two benzene molecules in aqueous and salt solutions. To investigate the structure and dynamics of the interface between benzene and water or salt solution.

  12. Benzene distribution in product streams from in-tank processing

    SciTech Connect (OSTI)

    Walker, D.D.

    1987-01-15

    Benzene is the major product of radiolytic decomposition of tetraphenylborate salts during in-tank salt decontamination. Its production rate has been measured at the Savannah River Laboratory (SR) and at the University of Florida under various conditions of importance to the in-tank process. Recent work has been concerned with the extent of decomposition for long storage periods, and the composition of the product streams from the process. The major results from this work are: the stored potassium tetraphenylborate precipitate will decompose at a rate of 7.3 {plus minus} 1.1% per year; the major products of the decomposition are benzene, phenol, biphenyl, and phenylboric acid; decomposition is directly proportional to the total dose and is unaffected by dose rate; the decomposition produces acidic compounds which will cause a decrease in the pH of the storage tank. 13 refs., 6 figs., 6 tabs.

  13. Tip-contact related low-bias negative differential resistance and rectifying effects in benzene–porphyrin–benzene molecular junctions

    SciTech Connect (OSTI)

    Cheng, Jue-Fei; Zhou, Liping E-mail: leigao@suda.edu.cn; Liu, Man; Yan, Qiang; Han, Qin; Gao, Lei E-mail: leigao@suda.edu.cn

    2014-11-07

    The electronic transport properties of benzene–porphyrin–benzene (BPB) molecules coupled to gold (Au) electrodes were investigated. By successively removing the front-end Au atoms, several BPB junctions with different molecule-electrode contact symmetries were constructed. The calculated current–voltage (I–V) curves depended strongly on the contact configurations between the BPB molecules and the Au electrodes. In particular, a significant low-voltage negative differential resistance effect appeared at ?0.3 V in the junctions with pyramidal electrodes on both sides. Along with the breaking of this tip-contact symmetry, the low-bias negative differential resistance effect gradually disappeared. This tip-contact may be ideal for use in the design of future molecular devices because of its similarity with experimental processes.

  14. Biocatalytic conversion of ethylene to ethylene oxide using an engineered toluene monooxygenase

    SciTech Connect (OSTI)

    Carlin, DA; Bertolani, SJ; Siegel, JB

    2015-01-01

    Mutants of toluene o-xylene monooxygenase are demonstrated to oxidize ethylene to ethylene oxide in vivo at yields of >99%. The best mutant increases ethylene oxidation activity by >5500-fold relative to the native enzyme. This is the first report of a recombinant enzyme capable of carrying out this industrially significant chemical conversion.

  15. Occupational Exposure to Benzene from Painting with Epoxy and Other High Performance Coatings

    SciTech Connect (OSTI)

    JAHN, STEVEN

    2005-04-20

    Following the discovery of trace benzene in paint products, an assessment was needed to determine potential for benzene exposures to exceed the established ACGIH Threshold Limit Value (TLV) during painting operations. Sample data was collected by area industrial hygienists for benzene during routine maintenance and construction activities at Savannah River Site. A set of available data from the IH database, Sentry, was analyzed to provide guidance to the industrial hygiene staff and draw conclusions on the exposure potential during typical painting operations.

  16. Electron localization in a mixed-valence diniobium benzene complex

    Office of Scientific and Technical Information (OSTI)

    £ 1 EDGE ARTICLE View Article Online View Journal | View Issue CrossMark <-click for updates Cite this: Chem. Sci., 2015, 6, 993 Electron localization in a mixed-valence diniobium benzene complexf Thomas L. Gianetti,a Gregory Nocton,*b Stefan G. Minasian,cd Nikolas Kaltsoyannis,*e A. L. David Kilcoyne,f Stosh A. Kozimor,d David K. Shuh,c Tolek Tyliszczak,f Robert G. Bergman*3 and John Arnold*3 Received 3rd September 2014 Accepted 17th October 2014 DOI: 10.1039/c4sc02705a

  17. Decomposition of toluene in a steady-state atmospheric-pressure glow discharge

    SciTech Connect (OSTI)

    Trushkin, A. N.; Grushin, M. E.; Kochetov, I. V.; Trushkin, N. I.; Akishev, Yu. S.

    2013-02-15

    Results are presented from experimental studies of decomposition of toluene (C{sub 6}H{sub 5}CH{sub 3}) in a polluted air flow by means of a steady-state atmospheric pressure glow discharge at different water vapor contents in the working gas. The experimental results on the degree of C{sub 6}H{sub 5}CH{sub 3} removal are compared with the results of computer simulations conducted in the framework of the developed kinetic model of plasma chemical decomposition of toluene in the N{sub 2}: O{sub 2}: H{sub 2}O gas mixture. A substantial influence of the gas flow humidity on toluene decomposition in the atmospheric pressure glow discharge is demonstrated. The main mechanisms of the influence of humidity on C{sub 6}H{sub 5}CH{sub 3} decomposition are determined. The existence of two stages in the process of toluene removal, which differ in their duration and the intensity of plasma chemical decomposition of C{sub 6}H{sub 5}CH{sub 3} is established. Based on the results of computer simulations, the composition of the products of plasma chemical reactions at the output of the reactor is analyzed as a function of the specific energy deposition and gas flow humidity. The existence of a catalytic cycle in which hydroxyl radical OH acts a catalyst and which substantially accelerates the recombination of oxygen atoms and suppression of ozone generation when the plasma-forming gas contains water vapor is established.

  18. Location of MTBE and toluene in the channel system of the zeolite mordenite: Adsorption and host-guest interactions

    SciTech Connect (OSTI)

    Arletti, Rossella; Martucci, Annalisa; Alberti, Alberto; Pasti, Luisa; Nassi, Marianna; Bagatin, Roberto

    2012-10-15

    This paper reports a study of the location of Methyl Tertiary Butyl Ether (MTBE) and toluene molecules adsorbed in the pores of the organophylic zeolite mordenite from an aqueous solution. The presence of these organic molecules in the zeolite channels was revealed by structure refinement performed by the Rietveld method. About 3 molecules of MTBE and 3.6 molecules of toluene per unit cell were incorporated into the cavities of mordenite, representing 75% and 80% of the total absorption capacity of this zeolite. In both cases a water molecule was localized inside the side pocket of mordenite. The saturation capacity determined by the adsorption isotherms, obtained by batch experiments, and the weight loss given by thermogravimetric (TG) analyses were in very good agreement with these values. The interatomic distances obtained after the structural refinements suggest MTBE could be connected to the framework through a water molecule, while toluene could be bonded to framework oxygen atoms. The rapid and high adsorption of these hydrocarbons into the organophylic mordenite zeolite makes this cheap and environmental friendly material a suitable candidate for the removal of these pollutants from water. - graphical abstract: Location of MTBE (a) and toluene (b) in mordenite channels (projection along the [001] direction). Highlights: Black-Right-Pointing-Pointer We investigated the MTBE and toluene adsorption process into an organophilic zeolite mordenite. Black-Right-Pointing-Pointer The presence of MTBE and toluene in mordenite was determined by X-ray diffraction studies. Black-Right-Pointing-Pointer About 3 molecules of MTBE and 3.6 molecules of toluene per unit cell were incorporated into the zeolite cavities. Black-Right-Pointing-Pointer MTBE is connected to the framework through a water molecule. Black-Right-Pointing-Pointer Toluene is directly bonded to framework oxygen atoms.

  19. Intermolecular C?H bond activation of benzene and pyridines by a vanadium(III) alkylidene including a stepwise conversion of benzene to a vanadium-benzyne complex

    SciTech Connect (OSTI)

    Andino, José G.; Kilgore, Uriah J.; Pink, Maren; Ozarowski, Andrew; Krzystek, J.; Telser, Joshua; Baik, Mu-Hyun; Mindiola, Daniel J.

    2012-01-20

    Breaking of the carbon-hydrogen bond of benzene and pyridine is observed with (PNP)V(CH{sub 2}tBu){sub 2} (1), and in the case of benzene, the formation of an intermediate benzyne complex (C) is proposed, and indirect proof of its intermediacy is provided by identification of (PNP)VO({eta}{sup 2}-C{sub 6}H{sub 4}) in combination with DFT calculations.

  20. Geographical distribution of benzene in air in northwestern Italy and personal exposure

    SciTech Connect (OSTI)

    Gilli, G.; Scursatone, E.; Bono, R.

    1996-12-01

    Benzene is a solvent strictly related to some industrial activities and to automotive emissions. After the reduction in lead content of fuel gasoline, and the consequent decrease in octane number, an increase in benzene and other aromatic hydrocarbons in gasoline occurred. Therefore, an increase in the concentration of these chemicals in the air as primary pollutants and as precursors of photochemical smog could occur in the future. The objectives of this study were to describe the benzene air pollution at three sites in northwestern Italy throughout 1991 and 1994; to examine the relationship between benzene air pollution in indoor, outdoor, and personal air as measured by a group of nonsmoking university students; and to determine the influence of environmental tobacco smoke on the level of benzene exposure in indoor air environments. The results indicate a direct relationship between population density and levels of contamination; an indoor/outdoor ratio of benzene air pollution higher than 1 during day and night; a similar level of personal and indoor air contamination; and a direct relationship between levels of personal exposure to benzene and intensity of exposure to tobacco smoke. Human exposure to airborne benzene has been found to depend principally on indoor air contamination not only in the home but also in many other confined environments. 29 refs., 2 figs., 6 tabs.

  1. Simulation of toluene decomposition in a pulse-periodic discharge operating in a mixture of molecular nitrogen and oxygen

    SciTech Connect (OSTI)

    Trushkin, A. N.; Kochetov, I. V.

    2012-05-15

    The kinetic model of toluene decomposition in nonequilibrium low-temperature plasma generated by a pulse-periodic discharge operating in a mixture of nitrogen and oxygen is developed. The results of numerical simulation of plasma-chemical conversion of toluene are presented; the main processes responsible for C{sub 6}H{sub 5}CH{sub 3} decomposition are identified; the contribution of each process to total removal of toluene is determined; and the intermediate and final products of C{sub 6}H{sub 5}CH{sub 3} decomposition are identified. It was shown that toluene in pure nitrogen is mostly decomposed in its reactions with metastable N{sub 2}(A{sub 3}{Sigma}{sub u}{sup +}) and N{sub 2}(a Prime {sup 1}{Sigma}{sub u}{sup -}) molecules. In the presence of oxygen, in the N{sub 2} : O{sub 2} gas mixture, the largest contribution to C{sub 6}H{sub 5}CH{sub 3} removal is made by the hydroxyl radical OH which is generated in this mixture exclusively due to plasma-chemical reactions between toluene and oxygen decomposition products. Numerical simulation showed the existence of an optimum oxygen concentration in the mixture, at which toluene removal is maximum at a fixed energy deposition.

  2. Anaerobic biodegradation of BTEX in aquifer material. Environmental research brief

    SciTech Connect (OSTI)

    Borden, R.C.; Hunt, M.J.; Shafer, M.B.; Barlaz, M.A.

    1997-08-01

    Laboratory and field experiments were conducted in two petroleum-contaminated aquifers to examine the anaerobic biodegradation of benzene, toluene, ethylbenzene and xylene isomers (BTEX) under ambient conditions. Aquifer material was collected from locations at the source, mid-plume and end-plume at both sites, incubated under ambient conditions, and monitored for disappearance of the test compounds. In the mid-plume location at the second site, in-situ column experiments were also conducted for comparison with the laboratory microscosm and field-scale results. In the end-plume microcosms, biodegradation was variable with extensive biodegradation in some microcosms and little or no biodegradation in others.

  3. Site-specific variability in BTEX biodegradation under denitrifying conditions

    SciTech Connect (OSTI)

    Kao, C.M.; Borden, R.C.

    1997-03-01

    Laboratory microcosm experiments were conducted to evaluate the feasibility of benzene, toluene, ethylbenzene, m-xylene, and o-xylene (BTEX) biodegradation under denitrifying conditions. Nine different sources of inocula, including contaminated and uncontaminated soil cores from four different sites and activated sludge, were used to establish microcosms. BTEX was not degraded under denitrifying conditions in microcosms inoculated with aquifer material from Rocky Point and Traverse City. However, rapid depletion of glucose under denitrifying conditions was observed in microcosms containing Rocky Point aquifer material. TEX degradation was observed in microcosms containing Rocky Point aquifer material. TEX degradation was observed in microcosms containing aquifer material from Fort Bragg and Sleeping Bear Dunes and sewage sludge. Benzene was recalcitrant in all microcosms tested. The degradation of o-xylene ceased after toluene, ethylbenzene, and m-xylene were depleted in the Fort Bragg and sludge microcosms, but o-xylene continued to degrade in microcosms with contaminated Sleeping Bear Dunes soil. The most probable number (MPN) of denitrifiers in these nine different inocula were measured using a microtiter technique. There was no correlation between the MPN of denitrifiers and the TEX degradation rate under denitrifying conditions. Experimental results indicate that the degradation sequence and TEX degradation rate under denitrifying conditions may differ among sites. Results also indicate that denitrification alone may not be a suitable bioremediation technology for gasoline-contaminated aquifers because of the inability of denitrifiers to degrade benzene.

  4. Process for hydrocracking carbonaceous material to provide fuels or chemical feed stock

    DOE Patents [OSTI]

    Duncan, Dennis A.

    1980-01-01

    A process is disclosed for hydrocracking coal or other carbonaceous material to produce various aromatic hydrocarbons including benzene, toluene, xylene, ethylbenzene, phenol and cresols in variable relative concentrations while maintaining a near constant maximum temperature. Variations in relative aromatic concentrations are achieved by changing the kinetic severity of the hydrocracking reaction by altering the temperature profile up to and quenching from the final hydrocracking temperature. The relative concentration of benzene to the alkyl and hydroxyl aromatics is increased by imposing increased kinetic severity above that corresponding to constant heating rate followed by immediate quenching at about the same rate to below the temperature at which dehydroxylation and dealkylation reactions appreciably occur. Similarly phenols, cresols and xylenes are produced in enhanced concentrations by adjusting the temperature profile to provide a reduced kinetic severity relative to that employed when high benzene concentrations are desired. These variations in concentrations can be used to produce desired materials for chemical feed stocks or for fuels.

  5. Electron localization in a mixed-valence diniobium benzene complex (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | DOE PAGES DOE PAGES Search Results Accepted Manuscript: Electron localization in a mixed-valence diniobium benzene complex « Prev Next » Title: Electron localization in a mixed-valence diniobium benzene complex Reaction of the neutral diniobium benzene complex {[Nb(BDI)NtBu]2(μ-C6H6)} (BDI = N,N'-diisopropylbenzene-β-diketiminate) with Ag[B(C6F5)4] results in a single electron oxidation to produce a cationic diniobium arene complex, {[Nb(BDI)NtBu]2(μ-C6H6)}{B(C6F5)4}.

  6. Numerical analysis of the effect of acetylene and benzene addition to low-pressure benzene-rich flat flames on polycyclic aromatic hydrocarbon formation

    SciTech Connect (OSTI)

    Kunioshi, Nilson; Komori, Seisaku; Fukutani, Seishiro

    2006-10-15

    A modification of the CHEMKIN II package has been proposed for modeling addition of an arbitrary species at an arbitrary temperature to an arbitrary distance from the burner along a flat flame. The modified program was applied to the problem of addition of acetylene or benzene to different positions of a 40-Torr, {phi}=2.4 benzene/O{sub 2}/40%-N{sub 2} premixed flame to reach final equivalence ratios of {phi}=2.5 and 2.681. The results obtained showed that acetylene addition to early positions of the flame led to significant increase in pyrene production rates, but pyrene concentrations were lower in the flames with acetylene addition in both the {phi}=2.5 and 2.681 cases. Addition of benzene to the flame did not alter pyrene production rates in either the {phi}=2.5 or 2.681 cases; however, for {phi}=2.5, pyrene concentrations increased with benzene addition, while for {phi}=2.681, pyrene contents decreased in comparison to the correspondent flames with no addition. Acetylene addition led to a significant increase in pyrene production rates, but the pyrene levels dropped due to increase in the flow velocity. Pyrene production rates were not sensitive to benzene addition, but pyrene contents increased with benzene addition when the flow velocity decreased. These results show that PAH concentration changes accompanying species addition to flames should be interpreted carefully, because an increase or decrease in the content of a PAH species does not necessarily reflect an effect on its formation rate or mechanism. (author)

  7. COSMIC-RAY-MEDIATED FORMATION OF BENZENE ON THE SURFACE OF SATURN'S MOON TITAN

    SciTech Connect (OSTI)

    Zhou Li; Zheng Weijun; Kaiser, Ralf I.; Landera, Alexander; Mebel, Alexander M.; Liang, Mao-Chang; Yung, Yuk L.

    2010-08-01

    The aromatic benzene molecule (C{sub 6}H{sub 6})-a central building block of polycyclic aromatic hydrocarbon molecules-is of crucial importance for the understanding of the organic chemistry of Saturn's largest moon, Titan. Here, we show via laboratory experiments and electronic structure calculations that the benzene molecule can be formed on Titan's surface in situ via non-equilibrium chemistry by cosmic-ray processing of low-temperature acetylene (C{sub 2}H{sub 2}) ices. The actual yield of benzene depends strongly on the surface coverage. We suggest that the cosmic-ray-mediated chemistry on Titan's surface could be the dominant source of benzene, i.e., a factor of at least two orders of magnitude higher compared to previously modeled precipitation rates, in those regions of the surface which have a high surface coverage of acetylene.

  8. Electron localization in a mixed-valence diniobium benzene complex

    SciTech Connect (OSTI)

    Gianetti, Thomas L.; Nocton, Grégory; Minasian, Stefan G.; Kaltsoyannis, Nikolas; Kilcoyne, A. L. David; Kozimor, Stosh A.; Shuh, David K.; Tyliszczak, Tolek; Bergman, Robert G.; Arnold, John

    2014-11-11

    Reaction of the neutral diniobium benzene complex {[Nb(BDI)NtBu]2(?-C6H6)} (BDI = N,N'-diisopropylbenzene-?-diketiminate) with Ag[B(C6F5)4] results in a single electron oxidation to produce a cationic diniobium arene complex, {[Nb(BDI)NtBu]2(?-C6H6)}{B(C6F5)4}. Investigation of the solid state and solution phase structure using single-crystal X-ray diffraction, cyclic voltammetry, magnetic susceptibility, and multinuclear NMR spectroscopy indicates that the oxidation results in an asymmetric molecule with two chemically inequivalent Nb atoms. Further characterization using density functional theory (DFT) calculations, UV-visible, Nb L3,2-edge X-ray absorption near-edge structure (XANES), and EPR spectroscopies supports assignment of a diniobium complex, in which one Nb atom carries a single unpaired electron that is not largely delocalized on the second Nb atom. During the oxidative transformation, one electron is removed from the ?-bonding HOMO, which causes a destabilization of the molecule and formation of an asymmetric product. Subsequent reactivity studies indicate that the oxidized product allows access to metal-based chemistry with substrates that did not exhibit reactivity with the starting neutral complex.

  9. Solubilities of toluene and n-octane in aqueous protosurfactant and surfactant solutions

    SciTech Connect (OSTI)

    Ho, P.C.

    1985-01-01

    The solubilities of toluene and n-octane in aqueous protosurfactant and surfactant solutins were determined at 25/sup 0/C. The protosurfactants studied are sodium salts of cyclohexanecarboxylic acid, 2,5-diisopropylbenzenesulfonic acid, and 3,5-diisopropyisalicylic acid. Each of them has six alkyl carbons (S /SUB AC/ =6) and does not form micelles in water. The two micelle-forming surfactants used are sodium n-hexanoate with six alkyl carbons (S /SUB AC/ =6) and sodium n-octanoate with eight alkyl carbons (S /SUB AC/ =8). In three-component systems of toluene or n-octane with water and organic salt (either protosurfactant or surfactant), the solubility of the hydrocarbon in the aqueous phase increases as the number of alkyl carbons of the organic salt and as the aqueous concentration of the organic salt increases. However, in this study we found that sodium 3,5-diisopropyisalicylate causes much more pronounced increases in hydrocarbon solubility than these two surfactants. Sodium 2,5-diisopropylbenzenesulfonate, although not as effective in solubilization as the salicylate, has much stronger hydrotropic properties for hydrocarbons than either of these two surfactants. Sodium cyclohexanoate, with a compact arrangement of the six alkyl carbons, shows a higher hydrotropic effect than sodium n-hexanoate.

  10. Interaction of toluene with two-color asymmetric laser fields: Controlling the directional emission of molecular hydrogen fragments

    SciTech Connect (OSTI)

    Kaziannis, S.; Kotsina, N.; Kosmidis, C.

    2014-09-14

    The interaction of toluene with strong asymmetric two-color laser irradiation of 40 fs duration is studied by means of Time of flight mass spectrometry. Highly energetic H{sub 2}{sup +} and H{sub 3}{sup +} fragment ions are produced through an isomerization process taking place within transient multiply charged parent ions. Comparative study of deuterium labeled toluene isotopes enables the discrimination between molecular hydrogen fragments formed exclusively within the CH{sub 3}- part from those that require hydrogen atom exchange between the former and the phenyl moiety. It is demonstrated that by manipulating the relative phase of the ?/2? field components the selective ionization of oriented toluene molecules can be used as a tool to control the directional emission of the H{sub 2}{sup +}, H{sub 3}{sup +} species.

  11. Diffusion of benzene confined in the oriented nanochannels of chrysotile asbestos fibers

    SciTech Connect (OSTI)

    Mamontov, E.; Kumzerov, Yu.A.; Vakhrushev, S.B.

    2005-11-01

    We used quasielastic neutron scattering to study the dynamics of benzene that completely fills the nanochannels of chrysotile asbestos fibers with a characteristic diameter of about 5 nm. The macroscopical alignment of the nanochannels in fibers provided an interesting opportunity to study anisotropy of the dynamics of confined benzene by means of collecting the data with the scattering vector either parallel or perpendicular to the fibers axes. The translational diffusive motion of benzene molecules was found to be isotropic. While bulk benzene freezes at 278.5 K, we observed the translational dynamics of the supercooled confined benzene on the time scale of hundreds of picoseconds even below 200 K, until at about 160 K its dynamics becomes too slow for the {mu}eV resolution of the neutron backscattering spectrometer. The residence time between jumps for the benzene molecules measured in the temperature range of 260 K to 320 K demonstrated low activation energy of 2.8 kJ/mol.

  12. Test of electron beam technology on Savannah River Laboratory low-activity aqueous waste for destruction of benzene, benzene derivatives, and bacteria

    SciTech Connect (OSTI)

    Dougal, R.A.

    1993-08-01

    High energy radiation was studied as a means for destroying hazardous organic chemical wastes. Tests were conducted at bench scale with a {sup 60}Co source, and at full scale (387 l/min) with a 1.5 MV electron beam source. Bench scale tests for both benzene and phenol included 32 permutations of water quality factors. For some water qualities, as much as 99.99% of benzene or 90% of phenol were removed by 775 krads of {sup 60}Co irradiation. Full scale testing for destruction of benzene in a simulated waste-water mix showed loss of 97% of benzene following an 800 krad dose and 88% following a 500 krad dose. At these loss rates, approximately 5 Mrad of electron beam irradiation is required to reduce concentrations from 100 g/l to drinking water quality (5 {mu}g/l). Since many waste streams are also inhabited by bacterial populations which may affect filtering operations, the effect of irradiation on those populations was also studied. {sup 60}Co and electron beam irradiation were both lethal to the bacteria studied at irradiation levels far lower than were necessary to remove organic contaminants.

  13. Hoe Creek groundwater restoration, 1989

    SciTech Connect (OSTI)

    Renk, R.R.; Crader, S.E.; Lindblom, S.R.; Covell, J.R.

    1990-01-01

    During the summer of 1989, approximately 6.5 million gallons of contaminated groundwater were pumped from 23 wells at the Hoe Creek underground coal gasification site, near Gillette, Wyoming. The organic contaminants were removed using activated carbon before the water was sprayed on 15.4 acres at the sites. Approximately 2647 g (5.8 lb) of phenols and 10,714 g (23.6 lb) of benzene were removed from the site aquifers. Phenols, benzene, toluene, ethylbenzene, and naphthalene concentrations were measured in 43 wells. Benzene is the only contaminant at the site exceeds the federal standard for drinking water (5 {mu}g/L). Benzene leaches into the groundwater and is slow to biologically degrade; therefore, the benzene concentration has remained high in the groundwater at the site. The pumping operation affected groundwater elevations across the entire 80-acre site. The water levels rebounded quickly when the pumping operation was stopped on October 1, 1989. Removing contaminated groundwater by pumping is not an effective way to clean up the site because the continuous release of benzene from coal tars is slow. Benzene will continue to leach of the tars for a long time unless its source is removed or the leaching rate retarded through mitigation techniques. The application of the treated groundwater to the surface stimulated plant growth. No adverse effects were noted or recorded from some 60 soil samples taken from twenty locations in the spray field area. 20 refs., 52 figs., 8 tabs.

  14. In utero exposure to benzene increases embryonic c-Myb and Pim-1 protein levels in CD-1 mice

    SciTech Connect (OSTI)

    Wan, Joanne; Winn, Louise M.

    2008-05-01

    Benzene is a known human leukemogen, but its role as an in utero leukemogen remains controversial. Epidemiological studies have correlated parental exposure to benzene with an increased incidence of childhood leukemias. We hypothesize that in utero exposure to benzene may cause leukemogenesis by affecting the embryonic c-Myb/Pim-1 signaling pathway and that this is mediated by oxidative stress. To investigate this hypothesis, pregnant CD-1 mice were treated with either 800 mg/kg of benzene or corn oil (i.p.) on days 10 and 11 of gestation and in some cases pretreated with 25 kU/kg of PEG-catalase. Phosphorylated and total embryonic c-Myb and Pim-1 protein levels were assessed using Western blotting and maternal and embryonic oxidative stress were assessed by measuring reduced to oxidized glutathione ratios. Our results show increased oxidative stress at 4 and 24 h after exposure, increased phosphorylated Pim-1 protein levels 4 h after benzene exposure, and increased Pim-1 levels at 24 and 48 h after benzene exposure. Embryonic c-Myb levels were elevated at 24 h after exposure. PEG-catalase pretreatment prevented benzene-mediated increases in embryonic c-Myb and Pim-1 protein levels, and benzene-induced oxidative stress. These results support a role for ROS in c-Myb and Pim-1 alterations after in utero benzene exposure.

  15. THE INFLUENCE OF BENZENE AS A TRACE REACTANT IN TITAN AEROSOL ANALOGS

    SciTech Connect (OSTI)

    Trainer, Melissa G.; Sebree, Joshua A.; Heidi Yoon, Y.; Tolbert, Margaret A.

    2013-03-20

    Benzene has been detected in Titan's atmosphere by Cassini instruments, with concentrations ranging from sub-ppb in the stratosphere to ppm in the ionosphere. Sustained levels of benzene in the haze formation region could signify that it is an important reactant in the formation of Titan's organic aerosol. To date, there have not been laboratory investigations to assess the influence of benzene on aerosol properties. We report a laboratory study on the chemical composition of organic aerosol formed from C{sub 6}H{sub 6}/CH{sub 4}/N{sub 2} via far ultraviolet irradiation (120-200 nm). The compositional results are compared to those from aerosol generated by a more ''traditional Titan'' mixture of CH{sub 4}/N{sub 2}. Our results show that even a trace amount of C{sub 6}H{sub 6} (10 ppm) has significant impact on the chemical composition and production rates of organic aerosol. There are several pathways by which photolyzed benzene may react to form larger molecules, both with and without the presence of CH{sub 4}, but many of these reaction mechanisms are only beginning to be explored for the conditions at Titan. Continued work investigating the influence of benzene in aerosol growth will advance understanding of this previously unstudied reaction system.

  16. Hydrogen-terminated silicon nanowire photocatalysis: Benzene oxidation and methyl red decomposition

    SciTech Connect (OSTI)

    Lian, Suoyuan; School of Chemical Engineering and Materials, Dalian Polytechnic University, Dalian 116034 ; Tsang, Chi Him A.; Centre of Super Diamond and Advanced Films, City University of Hong Kong, Hong Kong ; Kang, Zhenhui; Liu, Yang; Wong, Ningbew; Lee, Shuit-Tong; Centre of Super Diamond and Advanced Films, City University of Hong Kong, Hong Kong

    2011-12-15

    Graphical abstract: H-SiNWs can catalyze hydroxylation of benzene and degradation of methyl red under visible light irradiation. Highlights: Black-Right-Pointing-Pointer Hydrogen-terminated silicon nanowires were active photocatalyst in the hydroxylation of benzene under light. Black-Right-Pointing-Pointer Hydrogen-terminated silicon nanowires were also effective in the decomposition of methyl red dye. Black-Right-Pointing-Pointer The Si/SiO{sub x} core-shell structure is the main reason of the obtained high selectivity during the hydroxylation. -- Abstract: Hydrogen-terminated silicon nanowires (H-SiNWs) were used as heterogeneous photocatalysts for the hydroxylation of benzene and for the decomposition of methyl red under visible light irradiation. The above reactions were monitored by GC-MS and UV-Vis spectrophotometry, respectively, which shows 100% selectivity for the transformation of benzene to phenol. A complete decomposition of a 2 Multiplication-Sign 10{sup -4} M methyl red solution was achieved within 30 min. The high selectivity for the hydroxylation of benzene and the photodecomposition demonstrate the catalytic activity of ultrafine H-SiNWs during nanocatalysis.

  17. Total cross sections for positron scattering from benzene, cyclohexane, and aniline

    SciTech Connect (OSTI)

    Zecca, Antonio; Moser, Norberto; Perazzolli, Chiara; Salemi, Alessandro; Brunger, Michael J.

    2007-08-15

    We use a linear transmission technique to measure total cross sections for positron scattering from benzene, cyclohexane, and aniline. In the case of cyclohexane, the energy range of the present study is 0.1-20 eV, while for benzene and aniline it is 0.2-20 eV. With respect to benzene and cyclohexane, comparison is made to the only other existing results we know of [Makochekanwa and co-workers, Phys. Rev. A 68, 032707 (2003); 72, 042705 (2005)]. Agreement with those data is only marginal, being particularly poor at the overlap lower energies. Unlike Kimura et al. [J. Phys. B 37, 1461 (2004)], we find the low-energy dependence of the positron-benzene total cross sections to be qualitatively similar to those found in the electron channel [Gulley et al., J. Phys. B 31, 2735 (1998)]. We believe that the present positron-aniline total cross sections represent the first time such data have been measured. These cross sections are almost identical to those we found for benzene, suggesting that substitution of hydrogen by the amine group on the aromatic ring is largely irrelevant to the scattering process in the energy regimes considered.

  18. Final Technical Report - Autothermal Styrene Manufacturing Process with Net Export of Energy

    SciTech Connect (OSTI)

    Trubac, Robert , E.; Lin, Feng; Ghosh, Ruma: Greene, Marvin

    2011-11-29

    The overall objectives of the project were to: (a) develop an economically competitive processing technology for styrene monomer (SM) that would reduce process energy requirements by a minimum 25% relative to those of conventional technology while achieving a minimum 10% ROI; and (b) advance the technology towards commercial readiness. This technology is referred to as OMT (Oxymethylation of Toluene). The unique energy savings feature of the OMT technology would be replacement of the conventional benzene and ethylene feedstocks with toluene, methane in natural gas and air or oxygen, the latter of which have much lower specific energy of production values. As an oxidative technology, OMT is a net energy exporter rather than a net energy consumer like the conventional ethylbenzene/styrene (EB/SM) process. OMT plants would ultimately reduce the cost of styrene monomer which in turn will decrease the costs of polystyrene making it perhaps more cost competitive with competing polymers such as polypropylene.

  19. Revisiting benzene cluster cations for the chemical ionization of dimethyl sulfide and select volatile organic compounds

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kim, M. J.; Zoerb, M. C.; Campbell, N. R.; Zimmermann, K. J.; Blomquist, B. W.; Huebert, B. J.; Bertram, T. H.

    2015-10-01

    Benzene cluster cations were revisited as a sensitive and selective reagent ion for the chemical ionization of dimethyl sulfide (DMS) and a select group of volatile organic compounds (VOCs). Laboratory characterization was performed using both a new set of compounds (i.e. DMS, ?-caryophyllene) as well as previously studied VOCs (i.e., isoprene, ?-pinene). Using a field deployable chemical ionization time-of-flight mass spectrometer (CI-ToFMS), benzene cluster cations demonstrated high sensitivity (> 1 ncps ppt?1) to DMS, isoprene, and ?-pinene standards. Parallel measurements conducted using a chemical-ionization quadrupole mass spectrometer, with a weaker electric field, demonstrated that ion-molecule reactions likely proceed through amore »combination of ligand-switching and direct charge transfer mechanisms. Laboratory tests suggest that benzene cluster cations may be suitable for the selective ionization of sesquiterpenes, where minimal fragmentation (R2=0.80) over a wide range of sampling conditions.« less

  20. Theoretical study of reactions of HO{sub 2} in low-temperature oxidation of benzene

    SciTech Connect (OSTI)

    Altarawneh, Mohammednoor; Dlugogorski, Bogdan Z.; Kennedy, Eric M.; Mackie, John C.

    2010-07-15

    We have generated a set of thermodynamic and kinetic parameters for the reactions involving HO{sub 2} in the very early stages of benzene oxidation at low temperatures using density functional theory (DFT). In particular, we report the rate constants for the reactions of HO{sub 2} with benzene and phenyl. The calculated reaction rate constant for the abstraction of H-C{sub 6}H{sub 5} by HO{sub 2} is found to be in good agreement with the limited experimental values. HO{sub 2} addition to benzene is found to be more important than direct abstraction. We show that the reactions of HO{sub 2} with the phenyl radical generate the propagating radical OH in a highly exoergic reaction. The results presented herein should be useful in modeling the oxidation of aromatic compounds at low temperatures. (author)

  1. In utero and in vitro effects of benzene and its metabolites on erythroid differentiation and the role of reactive oxygen species

    SciTech Connect (OSTI)

    Badham, Helen J.; Winn, Louise M.

    2010-05-01

    Benzene is a ubiquitous occupational and environmental toxicant. Exposures to benzene both prenatally and during adulthood are associated with the development of disorders such as aplastic anemia and leukemia. Mechanisms of benzene toxicity are unknown; however, generation of reactive oxygen species (ROS) by benzene metabolites may play a role. Little is known regarding the effects of benzene metabolites on erythropoiesis. Therefore, to determine the effects of in utero exposure to benzene on the growth and differentiation of fetal erythroid progenitor cells (CFU-E), pregnant CD-1 mice were exposed to benzene and CFU-E numbers were assessed in fetal liver (hematopoietic) tissue. In addition, to determine the effect of benzene metabolite-induced ROS generation on erythropoiesis, HD3 chicken erythroblast cells were exposed to benzene, phenol, or hydroquinone followed by stimulation of erythrocyte differentiation. Our results show that in utero exposure to benzene caused significant alterations in female offspring CFU-E numbers. In addition, exposure to hydroquinone, but not benzene or phenol, significantly reduced the percentage of differentiated HD3 cells, which was associated with an increase in ROS. Pretreatment of HD3 cells with polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) prevented hydroquinone-induced inhibition of erythropoiesis, supporting the hypothesis that ROS generation is involved in the development of benzene erythrotoxicity. In conclusion, this study provided evidence that ROS generated as a result of benzene metabolism may significantly alter erythroid differentiation, potentially leading to the development of Blood Disorders.

  2. Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Niemeyer, Kyle E.; Sung, Chih-Jen

    2014-11-01

    Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, suchmore » as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.« less

  3. Formation and aging of secondary organic aerosol from toluene: changes in chemical composition, volatility, and hygroscopicity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hildebrandt Ruiz, L.; Paciga, A. L.; Cerully, K. M.; Nenes, A.; Donahue, N. M.; Pandis, S. N.

    2015-07-24

    Secondary organic aerosol (SOA) is transformed after its initial formation, but this chemical aging of SOA is poorly understood. Experiments were conducted in the Carnegie Mellon environmental chamber to form secondary organic aerosol (SOA) from the photo-oxidation of toluene and other small aromatic volatile organic compounds (VOCs) in the presence of NOx under different oxidizing conditions. The effects of the oxidizing condition on organic aerosol (OA) composition, mass yield, volatility, and hygroscopicity were explored. Higher exposure to the hydroxyl radical resulted in different OA composition, average carbon oxidation state (OSc), and mass yield. The OA oxidation state generally increased duringmore » photo-oxidation, and the final OA OSc ranged from -0.29 to 0.16 in the performed experiments. The volatility of OA formed in these different experiments varied by as much as a factor of 30, demonstrating that the OA formed under different oxidizing conditions can have a significantly different saturation concentration. There was no clear correlation between hygroscopicity and oxidation state for this relatively hygroscopic SOA.« less

  4. Mechanism reduction for multicomponent surrogates: A case study using toluene reference fuels

    SciTech Connect (OSTI)

    Niemeyer, Kyle E.; Sung, Chih-Jen

    2014-11-01

    Strategies and recommendations for performing skeletal reductions of multicomponent surrogate fuels are presented, through the generation and validation of skeletal mechanisms for a three-component toluene reference fuel. Using the directed relation graph with error propagation and sensitivity analysis method followed by a further unimportant reaction elimination stage, skeletal mechanisms valid over comprehensive and high-temperature ranges of conditions were developed at varying levels of detail. These skeletal mechanisms were generated based on autoignition simulations, and validation using ignition delay predictions showed good agreement with the detailed mechanism in the target range of conditions. When validated using phenomena other than autoignition, such as perfectly stirred reactor and laminar flame propagation, tight error control or more restrictions on the reduction during the sensitivity analysis stage were needed to ensure good agreement. In addition, tight error limits were needed for close prediction of ignition delay when varying the mixture composition away from that used for the reduction. In homogeneous compression-ignition engine simulations, the skeletal mechanisms closely matched the point of ignition and accurately predicted species profiles for lean to stoichiometric conditions. Furthermore, the efficacy of generating a multicomponent skeletal mechanism was compared to combining skeletal mechanisms produced separately for neat fuel components; using the same error limits, the latter resulted in a larger skeletal mechanism size that also lacked important cross reactions between fuel components. Based on the present results, general guidelines for reducing detailed mechanisms for multicomponent fuels are discussed.

  5. Biofiltration control of VOC and air toxic emissions: n-Butane and benzene

    SciTech Connect (OSTI)

    Allen, E.R.

    1996-12-31

    n-Butane and benzene vapors are routinely observed in urban atmospheres. Their presence in urban airsheds is of concern because of their ozone production potential as volatile organic compounds (VOCs) and/or potential toxicity. Also, these saturated hydrocarbons are representative of airborne aliphatic and aromatic compounds. Separate laboratory studies have been conducted on the biological elimination of n-butane (n-C{sub 4}H{sub 10}) and benzene (C{sub 6}H{sub 6}) from airstreams using treated compost biofilters. The removal efficiencies were found to exceed 90% for a conditioned biofilter medium and pollutant low concentrations (< 25 ppm) and zeroth order kinetics at higher concentrations (> 100 ppm), whereas benzene vapor elimination followed zeroth order kinetics at concentrations up to 200 ppm. The maximum n-butane and benzene elimination capacities observed for the compost biofilters and conditions employed were 25 and 70 g pollutant m{sup -3} h{sup -1}, respectively. 13 refs., 6 figs., 2 tabs.

  6. Formation of the diphenyl molecule in the crossed beam reaction of phenyl radicals with benzene

    SciTech Connect (OSTI)

    Zhang Fangtong; Gu Xibin; Kaiser, Ralf I.

    2008-02-28

    The chemical dynamics to form the D5-diphenyl molecule, C{sub 6}H{sub 5}C{sub 6}D{sub 5}, via the neutral-neutral reaction of phenyl radicals (C{sub 6}H{sub 5}) with D6-benzene (C{sub 6}D{sub 6}), was investigated in a crossed molecular beams experiment at a collision energy of 185 kJ mol{sup -1}. The laboratory angular distribution and time-of-flight spectra of the C{sub 6}H{sub 5}C{sub 6}D{sub 5} product were recorded at mass to charge m/z of 159. Forward-convolution fitting of our data reveals that the reaction dynamics are governed by an initial addition of the phenyl radical to the {pi} electron density of the D6-benzene molecule yielding a short-lived C{sub 6}H{sub 5}C{sub 6}D{sub 6} collision complex. The latter undergoes atomic deuterium elimination via a tight exit transition state located about 30 kJ mol{sup -1} above the separated reactants; the overall reaction to form D5-diphenyl from phenyl and D6-benzene was found to be weakly exoergic. The explicit identification of the D5-biphenyl molecules suggests that in high temperature combustion flames, a diphenyl molecule can be formed via a single collision event between a phenyl radical and a benzene molecule.

  7. Comparative Investigation of Benzene Steam Reforming over Spinel Supported Rh and Ir Catalysts

    SciTech Connect (OSTI)

    Mei, Donghai; Lebarbier, Vanessa MC; Rousseau, Roger J.; Glezakou, Vassiliki Alexandra; Albrecht, Karl O.; Kovarik, Libor; Flake, Matthew D.; Dagle, Robert A.

    2013-06-01

    In a combined experimental and first-principles density functional theory (DFT) study, benzene steam reforming (BSR) over MgAl2O4 supported Rh and Ir catalysts was investigated. Experimentally, it has been found that both highly dispersed Rh and Ir clusters (1-2 nm) on the MgAl2O4 spinel support are stable during the BSR in the temperature range of 700-850?C. Compared to the Ir/MgAl2O4 catalyst, the Rh/MgAl2O4 catalyst is more active with higher benzene turnover frequency and conversion. At typical steam conditions with the steam-to-carbon ratio > 12, the benzene conversion is only a weak function of the H2O concentration in the feed. This suggests that the initial benzene decomposition step rather than the benzene adsorption is most likely the rate-determined step in BSR over supported Rh and Ir catalysts. In order to understand the differences between the two catalysts, we followed with a comparative DFT study of initial benzene decomposition pathways over two representative model systems for each supported metal (Rh and Ir) catalysts. A periodic terrace (111) surface and an amorphous 50-atom metal cluster with a diameter of 1.0 nm were used to represent the two supported model catalysts under low and high dispersion conditions. Our DFT results show that the decreasing catalyst particle size enhances the benzene decomposition on supported Rh catalysts by lowering both C-C and C-H bond scission. The activation barriers of the C-C and the C-H bond scission decrease from 1.60 and 1.61 eV on the Rh(111) surface to 1.34 and 1.26 eV on the Rh50 cluster. For supported Ir catalysts, the decreasing particle size only affects the C-C scission. The activation barrier of the C-C scission of benzene decreases from 1.60 eV on the Ir(111) surface to 1.35 eV on the Ir50 cluster while the barriers of the C-H scission are practically the same. The experimentally measured higher BSR activity on the supported highly dispersed Rh catalyst can be rationalized by the thermodynamic limitation for the very first C-C bond scission of benzene on the small Ir50 catalyst. The C-C bond scission of benzene on the small Ir50 catalyst is highly endothermic although the barrier is competitive with the barriers of both the C-C and the C-H bond-breakings on the small Rh50 catalyst. The calculations also imply that, for the supported Rh catalysts the C-C and C-H bond scissions are competitive, independently of the Rh cluster sizes. After the initial dissociation step via either the C-C or the C-H bond scission, the C-H bond breaking seems to be more favorable rather than the C-C bond breaking on the larger Rh terrace surface. This work was financially supported by the United States Department of Energy’s Office of Biomass Program’s. Computing time was granted by a user project at the Molecular Science Computing Facility in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory.

  8. Products of the Benzene + O(3P) Reaction

    SciTech Connect (OSTI)

    Taatjes, Craig A.; Osborn, David L.; Selby, Talitha M.; Meloni, Giovanni; Trevitt, Adam J.; Epifanovsky, Evgeny; Krylov, Anna I.; Sirjean, Baptiste; Dames, Enoch; Wang, Hai

    2010-03-11

    The gas-phase reaction of benzene with O(3P) is of considerable interest for modeling of aromatic oxidation, and also because there exist fundamental questions concerning the prominence of intersystem crossing in the reaction. While its overall rate constant has been studied extensively, there are still significant uncertainties in the product distribution. The reaction proceeds mainly through the addition of the O atom to benzene, forming an initial triplet diradical adduct, which can either dissociate to form the phenoxy radical and H atom or undergo intersystem crossing onto a singlet surface, followed by a multiplicity of internal isomerizations, leading to several possible reaction products. In this work, we examined the product branching ratios of the reaction between benzene and O(3P) over the temperature range 300-1000 K and pressure range 1-10 Torr. The reactions were initiated by pulsed-laser photolysis of NO2 in the presence of benzene and helium buffer in a slow-flow reactor, and reaction products were identified by using the multiplexed chemical kinetics photoionization mass spectrometer operating at the Advanced Light Source (ALS) of Lawrence Berkeley National Laboratory. Phenol and phenoxy radical were detected and quantified. Cyclopentadiene and cyclopentadienyl radical were directly identified for the first time. Finally, ab initio calculations and master equation/RRKM modeling were used to reproduce the experimental branching ratios, yielding pressure-dependent rate expressions for the reaction channels, including phenoxy + H, phenol, cyclopentadiene + CO, which are proposed for kinetic modeling of benzene oxidation.

  9. On the role of delocalization in benzene: Theoretical and experimental investigation of the effects of strained ring fusion

    SciTech Connect (OSTI)

    Faust, R.

    1993-04-01

    When an important compound`s discovery dates back as far as 1825, one would imagine that every facet of its chemical and physical properties has been illuminated in the meantime. Benzene, however, has not ceased to challenge the chemist`s notion of structure and bonding since its first isolation by Michael Faraday. This report is divided into the following six chapters: 1. Aromaticity -- Criteria, manifestations, structural limitations; 2. The role of delocalization in benzene; 3. The thermochemical properties of benzocyclobutadienologs; 4. Ab initio study of benzenes fused to four-membered rings; 5. Non-planar polycyclic aromatic hydrocarbons; and 6. Experimental details and input decks. 210 Refs.

  10. Modeling Studies on the Transport of Benzene and H2S in CO2-Water Systems

    SciTech Connect (OSTI)

    Zheng, L.; Spycher, N.; Xu, T.; Apps, J.; Kharaka, Y.; Birkholzer, J.T.

    2010-11-05

    In this study, reactive transport simulations were used to assess the mobilization and transport of organics with supercritical CO{sub 2} (SCC), and the co-injection and transport of H{sub 2}S with SCC. These processes were evaluated at conditions of typical storage reservoirs, and for cases of hypothetical leakage from a reservoir to an overlying shallower fresh water aquifer. Modeling capabilities were developed to allow the simulation of multiphase flow and transport of H{sub 2}O, CO{sub 2}, H{sub 2}S, as well as specific organic compounds (benzene), coupled with multicomponent geochemical reaction and transport. This included the development of a new simulator, TMVOC-REACT, starting from existing modules of the TOUGH2 family of codes. This work also included an extensive literature review, calculation, and testing of phase-partitioning properties for mixtures of the phases considered. The reactive transport simulations presented in this report are primarily intended to illustrate the capabilities of the new simulator. They are also intended to help evaluate and understand various processes at play, in a more qualitative than quantitative manner, and only for hypothetical scenarios. Therefore, model results are not intended as realistic assessments of groundwater quality changes for specific locations, and they certainly do not provide an exhaustive evaluation of all possible site conditions, especially given the large variability and uncertainty in hydrogeologic and geochemical parameter input into simulations. The first step in evaluating the potential mobilization and transport of organics was the identification of compounds likely to be present in deep storage formations, and likely to negatively impact freshwater aquifers if mobilized by SCC. On the basis of a literature review related to the occurrence of these organic compounds, their solubility in water and SCC, and their toxicity (as reflected by their maximum contaminant levels MCL), benzene was selected as a key compound for inclusion into numerical simulations. Note that considering additional organic compounds and/or mixtures of such compounds in the simulations was beyond the scope of this study, because of the effort required to research, calculate, and validate the phase-partitioning data necessary for simulations. The injection of CO{sub 2} into a deep saline aquifer was simulated, followed by modeling the leaching of benzene by SCC and transport of benzene to an overlying aquifer along a hypothetical leakage pathway. One- and two-dimensional models were set up for this purpose. The target storage formation was assumed to initially contain about 10{sup -4} ppm benzene. Model results indicate that: (1) SCC efficiently extracts benzene from the storage formation. (2) Assuming equilibrium, the content of benzene in SCC is roportional to the concentration of benzene in the aqueous and solid phases. (3) Benzene may co-migrate with CO{sub 2} into overlying aquifers if a leakage pathway is present. Because the aqueous solubility of benzene in contact with CO{sub 2} is lower than the aqueous solubility of CO{sub 2}, benzene is actually enriched in the CO{sub 2} phase as the plume advances. (4) For the case studied here, the resulting aqueous benzene concentration in the overlying aquifer is on the same order of magnitude as the initial concentration in the storage formation. This generic modeling study illustrates, in a semi-quantitative manner, the possible mobilization of benzene by SCC. The extent to which the mobilization of this organic compound evolves temporally and spatially depends on a large number of controlling parameters and is largely site specific. Therefore, for more 'truly' predictive work, further sensitivity studies should be conducted, and further modeling should be integrated with site-specific laboratory and/or field experimental data. The co-injection of H{sub 2}S with CO{sub 2} into a deep saline aquifer was also simulated. In addition, the model considered leakage of the supercritical CO{sub 2}+H{sub 2}S mixture along a preferential pathway to an overlying fresh-water aquifer, followed by reaction of the CO{sub 2}+H{sub 2}S mixture with that aquifer. A simple 2-D model that included a storage formation and a sealing aquitard was developed to simulate the movement of H{sub 2}S in a typical CO{sub 2} storage formation. Model results indicate that H{sub 2}S is stripped off at the edge of the advancing supercritical plume, because of the H{sub 2}S preferential solubility in water compared to CO{sub 2}. The magnitude of H{sub 2}S preferential dissolution, however, decreases with decreasing temperature and pressure. To capture this behavior and evaluate the breakthrough of H{sub 2}S through a leakage pathway (from the deep storage formation to a shallower aquifer), another model was constructed, considering a storage formation, an overlying aquifer, and a vertical leakage pathway between them.

  11. Crystallographic Analysis of Active Site Contributions to Regiospecificity in the Diiron Enzyme Toluene 4-Monooxygenase

    SciTech Connect (OSTI)

    Bailey, Lucas J.; Acheson, Justin F.; McCoy, Jason G.; Elsen, Nathaniel L.; Phillips, Jr., George N.; Fox, Brian G.

    2014-10-02

    Crystal structures of toluene 4-monooxygenase hydroxylase in complex with reaction products and effector protein reveal active site interactions leading to regiospecificity. Complexes with phenolic products yield an asymmetric {mu}-phenoxo-bridged diiron center and a shift of diiron ligand E231 into a hydrogen bonding position with conserved T201. In contrast, complexes with inhibitors p-NH{sub 2}-benzoate and p-Br-benzoate showed a {mu}-1,1 coordination of carboxylate oxygen between the iron atoms and only a partial shift in the position of E231. Among active site residues, F176 trapped the aromatic ring of products against a surface of the active site cavity formed by G103, E104 and A107, while F196 positioned the aromatic ring against this surface via a {pi}-stacking interaction. The proximity of G103 and F176 to the para substituent of the substrate aromatic ring and the structure of G103L T4moHD suggest how changes in regiospecificity arise from mutations at G103. Although effector protein binding produced significant shifts in the positions of residues along the outer portion of the active site (T201, N202, and Q228) and in some iron ligands (E231 and E197), surprisingly minor shifts (<1 {angstrom}) were produced in F176, F196, and other interior residues of the active site. Likewise, products bound to the diiron center in either the presence or absence of effector protein did not significantly shift the position of the interior residues, suggesting that positioning of the cognate substrates will not be strongly influenced by effector protein binding. Thus, changes in product distributions in the absence of the effector protein are proposed to arise from differences in rates of chemical steps of the reaction relative to motion of substrates within the active site channel of the uncomplexed, less efficient enzyme, while structural changes in diiron ligand geometry associated with cycling between diferrous and diferric states are discussed for their potential contribution to product release.

  12. Adsorption characteristics of benzene on biosolid adsorbent and commercial activated carbons

    SciTech Connect (OSTI)

    Hung-Lung Chiang; Kuo-Hsiung Lin; Chih-Yu Chen; Ching-Guan Choa; Ching-Shyung Hwu; Nina Lai

    2006-05-15

    This study selected biosolids from a petrochemical wastewater treatment plant as the raw material. The sludge was immersed in 0.5-5 M of zinc chloride (ZnCl{sub 2}) solutions and pyrolyzed at different temperatures and times. Results indicated that the 1-M ZnCl{sub 2}-immersed biosolids pyrolyzed at 500{sup o}C for 30 min could be reused and were optimal biosolid adsorbents for benzene adsorption. Pore volume distribution analysis indicated that the mesopore contributed more than the macropore and micropore in the biosolid adsorbent. The benzene adsorption capacity of the biosolid adsorbent was 65 and 55% of the G206 (granular-activated carbon) and BPL (coal-based activated carbon; Calgon, Carbon Corp.) activated carbons, respectively. Data from the adsorption and desorption cycles indicated that the benzene adsorption capacity of the biosolid adsorbent was insignificantly reduced compared with the first-run capacity of the adsorbent; therefore, the biosolid adsorbent could be reused as a commercial adsorbent, although its production cost is high. 18 refs., 9 figs., 3 tabs.

  13. Molecular Characterization of Brown Carbon (BrC) Chromophores in Secondary Organic Aerosol Generated From Photo-Oxidation of Toluene

    SciTech Connect (OSTI)

    Lin, Peng; Liu, Jiumeng; Shilling, John E.; Kathmann, Shawn M.; Laskin, Julia; Laskin, Alexander

    2015-09-28

    Atmospheric Brown carbon (BrC) is a significant contributor to light absorption and climate forcing. However, little is known about a fundamental relationship between the chemical composition of BrC and its optical properties. In this work, light-absorbing secondary organic aerosol (SOA) was generated in the PNNL chamber from toluene photo-oxidation in the presence of NOx (Tol-SOA). Molecular structures of BrC components were examined using nanospray desorption electrospray ionization (nano-DESI) and liquid chromatography (LC) combined with UV/Vis spectroscopy and electrospray ionization (ESI) high-resolution mass spectrometry (HRMS). The chemical composition of BrC chromophores and the light absorption properties of toluene SOA (Tol-SOA) depend strongly on the initial NOx concentration. Specifically, Tol-SOA generated under high-NOx conditions (defined here as initial NOx/toluene of 5/1) appears yellow and mass absorption coefficient of the bulk sample (MACbulk@365nm = 0.78 m2 g-1) is nearly 80 fold higher than that measured for the Tol-SOA sample generated under low-NOx conditions (NOx/toluene < 1/300). Fifteen compounds, most of which are nitrophenols, are identified as major BrC chromophores responsible for the enhanced light absorption of Tol-SOA material produced in the presence of NOx. The integrated absorbance of these fifteen chromophores accounts for 40-60% of the total light absorbance by Tol-SOA at wavelengths between 300 nm and 500 nm. The combination of tandem LC-UV/Vis-ESI/HRMS measurements provides an analytical platform for predictive understanding of light absorption properties by BrC and their relationship to the structure of individual chromophores. General trends in the UV/vis absorption by plausible isomers of the BrC chromophores were evaluated using theoretical chemistry calculations. The molecular-level understanding of BrC chemistry is helpful for better understanding the evolution and behavior of light absorbing aerosols in the atmosphere.

  14. An Order-of-Magnitude Estimation of Benzene Concentration in Saltstone Vault

    SciTech Connect (OSTI)

    CHOI, A

    2006-03-20

    The contents of Tank 48H that include the tetraphenylborate (TPB) precipitates of potassium and cesium will be grouted and stored in the Saltstone vault. The grouting process is exothermic, which should accelerate the rate of decomposition of TPB precipitates eventually to benzene. Because the vault is not currently outfitted with an active ventilation system, there is a concern that a mixture of flammable gases may form in the vapor space of each cell filled with the curing grout. The purpose of this study was to determine if passive breathing induced by the diurnal fluctuations of barometric pressure would provide any mitigating measure against potential flammability in the cell vapor space. In Revision 0 of this document, a set of algorithms were presented that would predict the equilibrium concentration of benzene in the cell vapor space as a function of benzene generation rate, fill height, and passive breathing rate. The algorithms were derived based on several simplifying assumptions so that order of magnitude estimates could be made quickly for scoping purposes. In particular, it was assumed that passive breathing would occur solely due to barometric pressure fluctuations that were sinusoidal; the resulting algorithm for estimating the rate of passive breathing into or out of each cell is given in Eq. (10). Since Revision 0 was issued, the validity of this critical assumption on the mode of passive breathing was checked against available passive ventilation data for the Hanford waste tanks. It was found that the passive breathing rates estimated from Eq. (10) were on average 50 to 90% lower than those measured for 5 out of 6 Hanford tanks considered in this study (see Table 1); for Tank U-106, the estimated passive breathing rates were on average 20% lower than the measured data. These results indicate that Eq. (10) would most likely under predict passive breathing rates of the Saltstone vault. At a given fill height and benzene generation rate, under predicted breathing rates would in turn make the benzene concentration projections in the cell vapor space conservatively high, thus rendering the overall flammability assessment conservative. The results of this validation effort are summarized in Section 2.4 of this revision. It is to be noted that all the algorithms, numerical results and conclusions made in Revision 0 remain valid. In this work, the algorithms for estimating the equilibrium benzene concentration for a given scenario were derived by combining the asymptotic solutions to the transient mass balance equations for the exhaling and inhaling modes in a 24-hour period. These algorithms were then applied to simulate several test cases, including the baseline case where the cell was filled to the maximum height of 25 ft at the bulk benzene generation rate of 3.4 g/hr.

  15. Benzene under high pressure: A story of molecular crystals transforming to saturated networks, with a possible intermediate metallic phase

    SciTech Connect (OSTI)

    Wen, Xiao-Dong; Hoffmann, Roald; Ashcroft, N. W.

    2011-01-01

    In a theoretical study, benzene is compressed up to 300 GPa. The transformations found between molecular phases generally match the experimental findings in the moderate pressure regime (<20 GPa): phase I (Pbca) is found to be stable up to 4 GPa, while phase II (P43212) is preferred in a narrow pressure range of 4–7 GPa. Phase III (P21/c) is at lowest enthalpy at higher pressures. Above 50 GPa, phase V (P21 at 0 GPa; P21/c at high pressure) comes into play, slightly more stable than phase III in the range of 50–80 GP, but unstable to rearrangement to a saturated, four-coordinate (at C), one-dimensional polymer. Actually, throughout the entire pressure range, crystals of graphane possess lower enthalpy than molecular benzene structures; a simple thermochemical argument is given for why this is so. In several of the benzene phases there nevertheless are substantial barriers to rearranging the molecules to a saturated polymer, especially at low temperatures. Even at room temperature these barriers should allow one to study the effect of pressure on the metastable molecular phases. Molecular phase III (P21/c) is one such; it remains metastable to higher pressures up to ~200 GPa, at which point it too rearranges spontaneously to a saturated, tetracoordinate CH polymer. At 300 K the isomerization transition occurs at a lower pressure. Nevertheless, there may be a narrow region of pressure, between P = 180 and 200 GPa, where one could find a metallic, molecular benzene state. We explore several lower dimensional models for such a metallic benzene. We also probe the possible first steps in a localized, nucleated benzene polymerization by studying the dimerization of benzene molecules. Several new (C6H6)2 dimers are predicted.

  16. The flash pyrolysis and methanolysis of biomass (wood) for production of ethylene, benzene and methanol

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.T.; Sundaram, M.S.

    1990-02-01

    The process chemistry of the flash pyrolysis of biomass (wood) with the reactive gases, H{sub 2} and CH{sub 4} and with the non-reactive gases He and N{sub 2} is being determined in a 1 in. downflow tubular reactor at pressures from 20 to 1000 psi and temperatures from 600 to 1000{degrees}C. With hydrogen, flash hydropyrolysis leads to high yields of methane and CO which can be used for SNG and methanol fuel production. With methane, flash methanolysis leads to high yields of ethylene, benzene and CO which can be used for the production of valuable chemical feedstocks and methanol transportation fuel. At reactor conditions of 50 psi and 1000{degrees}C and approximately 1 sec residence time, the yields based on pine wood carbon conversion are up to 25% for ethylene, 25% for benzene, and 45% for CO, indicating that over 90% of the carbon in pine is converted to valuable products. Pine wood produces higher yields of hydrocarbon products than Douglas fir wood; the yield of ethylene is 2.3 times higher with methane than with helium or nitrogen, and for pine, the ratio is 7.5 times higher. The mechanism appears to be a free radical reaction between CH{sub 4} and the pyrolyzed wood. There appears to be no net production or consumption of methane. A preliminary process design and analysis indicates a potentially economical competitive system for the production of ethylene, benzene and methanol based on the methanolysis of wood. 10 refs., 18 figs., 1 tab.

  17. The benzene metabolite trans,trans-muconaldehyde blocks gap junction intercellular communication by cross-linking connexin43

    SciTech Connect (OSTI)

    Rivedal, Edgar Leithe, Edward

    2008-11-01

    Benzene is used at large volumes in many different human activities. Hematotoxicity and cancer-causation as a result of benzene exposure was recognized many years ago, but the mechanisms involved remain unclear. Aberrant regulation of gap junction intercellular communication (GJIC) has been linked to both cancer induction and interference with normal hematopoietic development. We have previously suggested that inhibition of GJIC may play a role in benzene toxicity since benzene metabolites were found to block GJIC, the ring-opened trans,trans-muconaldehyde (MUC) being the most potent metabolite. In the present work we have studied the molecular mechanisms underlying the MUC-induced inhibition of gap junctional communication. We show that MUC induces cross-linking of the gap junction protein connexin43 and that this is likely to be responsible for the induced inhibition of GJIC, as well as the loss of connexin43 observed in Western blots. We also show that glutaraldehyde possesses similar effects as MUC, and we compare the effects to that of formaldehyde. The fact that glutaraldehyde and formaldehyde have been associated with induction of leukemia as well as disturbance of hematopoiesis, strengthens the possible link between the effect of MUC on gap junctions, and the toxic effects of benzene.

  18. JV Task 86 - Identifying the Source of Benzene in Indoor Air Using Different Compound Classes from TO-15 Data

    SciTech Connect (OSTI)

    Steven B. Hawthorne

    2007-04-15

    Volatile organic compound (VOC) data that had already been collected using EPA method TO-15 at four different sites under regulatory scrutiny (a school, strip mall, apartment complex, and business/residential neighborhood) were evaluated to determine whether the source of indoor air benzene was outdoor air or vapor intrusion from contaminated soil. Both the use of tracer organics characteristic of different sources and principal component statistical analysis demonstrated that the source of indoor air at virtually all indoor sampling locations was a result of outdoor air, and not contaminated soil in and near the indoor air-sampling locations. These results show that proposed remediation activities to remove benzene-contaminated soil are highly unlikely to reduce indoor air benzene concentrations. A manuscript describing these results is presently being prepared for submission to a peer-reviewed journal.

  19. Evolution of soot size distribution in premixed ethylene/air and ethylene/benzene/air flames: Experimental and modeling study

    SciTech Connect (OSTI)

    Echavarria, Carlos A.; Sarofim, Adel F.; Lighty, JoAnn S.; D'Anna, Andrea

    2011-01-15

    The effect of benzene concentration in the initial fuel on the evolution of soot size distribution in ethylene/air and ethylene/benzene/air flat flames was characterized by experimental measurements and model predictions of size and number concentration within the flames. Experimentally, a scanning mobility particle sizer was used to allow spatially resolved and online measurements of particle concentration and sizes in the nanometer-size range. The model couples a detailed kinetic scheme with a discrete-sectional approach to follow the transition from gas-phase to nascent particles and their coagulation to larger soot particles. The evolution of soot size distribution (experimental and modeled) in pure ethylene and ethylene flames doped with benzene showed a typical nucleation-sized (since particles do not actually nucleate in the classical sense particle inception is often used in place of nucleation) mode close to the burner surface, and a bimodal behavior at greater height above burner (HAB). However, major features were distinguished between the data sets. The growth of nucleation and agglomeration-sized particles was faster for ethylene/benzene/air flames, evidenced by the earlier presence of bimodality in these flames. The most significant changes in size distribution were attributed to an increase in benzene concentration in the initial fuel. However, these changes were more evident for high temperature flames. In agreement with the experimental data, the model also predicted the decrease of nucleation-sized particles in the postflame region for ethylene flames doped with benzene. This behavior was associated with the decrease of soot precursors after the main oxidation zone of the flames. (author)

  20. Adsorption, Desorption, and Dissociation of Benzene on TiO2(110) and Pd/TiO2(110)

    SciTech Connect (OSTI)

    Zhou, Jing; Dag, Sefa; Senanayake, Sanjaya D; Hathorn, Bryan C; Kalinin, Sergei V; Meunier, Vincent; Mullins, David R; Overbury, Steven {Steve} H; Baddorf, Arthur P

    2006-01-01

    Adsorption and reaction of benzene molecules on clean TiO{sub 2}(110) and on TiO{sub 2}(110) with deposited Pd nanoparticles are investigated using a combination of scanning tunneling microscopy (STM), temperature-programmed desorption, and first-principles calculations. Above {approx}50 K, the one-dimensional motion of benzene between bridging oxygen rows is shown to be too fast for STM imaging. At 40 K benzene molecules form chains on top of titanium rows, with calculations indicating every other benzene is rotated 30{sup o}. Both experimental and theoretical studies find no dissociative reactivity of benzene on the clean TiO{sub 2}(110) surface, due to little hybridization between TiO{sub 2} and benzene electronic states. After deposition of Pd nanoparticles, molecular benzene is observed with STM both on the substrate and adjacent to metallic particles. Upon heating to 800 K, benzene fully breaks down into its atomic constituents in a multistep decomposition process.

  1. Natural bioreclamation of alkylbenzenes (BTEX) from a gasoline spill in methanogenic groundwater. Book chapter

    SciTech Connect (OSTI)

    Wilson, J.T.; Kampbell, D.H.; Armstrong, J.

    1994-01-01

    A spill of gasoline from underground storage tanks (USTS) at the Sleeping Bear Dunes National Lakeshore in Benzie County, Michigan, produced a plume of contamination that reached the banks of the Platte River. The plume was short (70 feet) and it had a short residence time (5 to 53 weeks). The plume was in transmissive glacial sands and gravels. The groundwater is cold (10 to 11 C), hard (alkalinity 200 to 350 milligrams/L), and well buffered (pH 6.1 to 7.6). Along the most contaminated flow path, methanogenesis, nitrate reduction, sulfate reduction, iron reduction, and oxygen respiration accepted enough electrons to destroy 30, 14, 4.2, 1.1, and 0.8 milligrams/L of benzene, toluene, ethylbenzene, and xylenes (BTEX compounds) respectively. The actual concentration of BTEX compounds consumed was 42 milligrams/L.

  2. In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents

    DOE Patents [OSTI]

    Taylor, Robert T.; Jackson, Kenneth J.; Duba, Alfred G.; Chen, Ching-I

    1998-01-01

    An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating.

  3. In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents

    DOE Patents [OSTI]

    Taylor, R.T.; Jackson, K.J.; Duba, A.G.; Chen, C.I.

    1998-05-19

    An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants are described. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating. 21 figs.

  4. Eielson Air Force Base Operable Unit 2 baseline risk assessment

    SciTech Connect (OSTI)

    Lewis, R.E.; Jarvis, T.T.; Jarvis, M.R.; Whelan, G.

    1994-10-01

    Operable Unit 2 at Eielson Air Force Base (AFB) near Fairbanks, is one of several operable units characterized by petroleum, oil, and lubricant contamination, and by the presence of organic products floating at the water table, as a result of Air Force operations since the 1940s. The base is approximately 19,270 acres in size, and comprises the areas for military operations and a residential neighborhood for military dependents. Within Operable Unit 2, there are seven source areas. These source areas were grouped together primarily because of the contaminants released and hence are not necessarily in geographical proximity. Source area ST10 includes a surface water body (Hardfill Lake) next to a fuel spill area. The primary constituents of concern for human health include benzene, toluene, ethylbenzene, and xylenes (BTEX). Monitored data showed these volatile constituents to be present in groundwater wells. The data also showed an elevated level of trace metals in groundwater.

  5. Health assessment for Vogel Paint and Wax, Maurice, Sioux County, Iowa, Region 7. CERCLIS No. IAD980630487. Final report

    SciTech Connect (OSTI)

    Not Available

    1989-04-29

    The Vogel Paint and Wax National Priority List site is situated in northwest Iowa in Sioux County. Contaminants found at the site consist of heavy metals (particularly cadmium, chromium, lead, and mercury) and volatile organic compounds (benzene, ethylbenzene, methyl ethyl ketone, toluene, and xylene). Two towns, Maurice and Struble, and the Southern Sioux County Rural Water System well field are located within three miles of the site, and two families live within 1600 feet of the waste-disposal site. Environmental pathways include contaminated soil and ground water, as well as potential surface water and air contamination. Although there does not appear to be any immediate public health threat, the site is of potential health concern because of the possibility for further off-site migration of contaminants into the ground water aquifer and for direct on-site contact.

  6. Thermodynamic Features of Benzene-1,2-Diphosphonic Acid Complexes with Several Metal Ions

    SciTech Connect (OSTI)

    Syouhei Nishihama; Ryan P. Witty; Leigh R Martin; Kenneth L. Nash

    2013-08-01

    Among his many contributions to the advancement of f-element chemistry and separation science, Professor Gregory R. Choppin’s research group completed numerous investigations featuring the application of distribution techniques to the determination of metal complexation equilibrium quotients. Most of these studies focused on the chemistry of lanthanide and actinide complexes. In keeping with that tradition, this report discusses the complex formation equilibrium constants for complexes of trivalent europium (Eu3+) with benzene-1,2-diphosphonic acid (H4BzDP) determined using solvent extraction distribution experiments in 0.2 M (Na,H)ClO4 media in the temperature range of 5 – 45 degrees C. Protonation constants for HnBzDP4-n and stoichiometry and stability of BzDP4- complexes with Zn2+, Ni2+, and Cu2+ have also been determined using potentiometric titration (at I = 0.1 M) and 31P NMR spectroscopy. Heats of protonation of HnBzDPn-4 species have been determined by titration calorimetry. From the temperature dependence of the complex Eu3+-HnBzDPn-4 equilibrium constant, a composite enthalpy (?H = -15.1 (+/-1.0) kJ mol-1) of complexation has been computed. Comparing these thermodynamic parameters with literature reports on other diphosphonic acids and structurally similar carboxylic acids indicates that exothermic heats of complexation are unique to the Eu-BzDP system. Comparisons with thermodynamic data from the literature indicate that the fixed geometry imposed by the benzene ring enhances complex stability.

  7. Changes in the peripheral blood transcriptome associated with occupational benzene exposure identified by cross-comparison on two microarray platforms

    SciTech Connect (OSTI)

    McHale, Cliona M.; Zhang, Luoping; Lan, Qing; Li, Guilan; Hubbard, Alan E.; Forrest, Matthew S.; Vermeulen, Roel; Chen, Jinsong; Shen, Min; Rappaport, Stephen M.; Yin, Songnian; Smith, Martyn T.; Rothman, Nathaniel

    2009-03-01

    Benzene is an established cause of leukemia and a possible cause of lymphoma in humans but the molecular pathways underlying this remain largely undetermined. This study sought to determine if the use of two different microarray platforms could identify robust global gene expression and pathway changes associated with occupational benzene exposure in the peripheral blood mononuclear cell (PBMC) gene expression of a population of shoe-factory workers with well-characterized occupational exposures to benzene. Microarray data was analyzed by a robust t-test using a Quantile Transformation (QT) approach. Differential expression of 2692 genes using the Affymetrix platform and 1828 genes using the Illumina platform was found. While the overall concordance in genes identified as significantly associated with benzene exposure between the two platforms was 26% (475 genes), the most significant genes identified by either array were more likely to be ranked as significant by the other platform (Illumina = 64%, Affymetrix = 58%). Expression ratios were similar among the concordant genes (mean difference in expression ratio = 0.04, standard deviation = 0.17). Four genes (CXCL16, ZNF331, JUN and PF4), which we previously identified by microarray and confirmed by real-time PCR, were identified by both platforms in the current study and were among the top 100 genes. Gene Ontology analysis showed over representation of genes involved in apoptosis among the concordant genes while Ingenuity{reg_sign} Pathway Analysis (IPA) identified pathways related to lipid metabolism. Using a two-platform approach allows for robust changes in the PBMC transcriptome of benzene-exposed individuals to be identified.

  8. Photocatalytic degradation of gaseous toluene over TiO{sub 2}-SiO{sub 2} composite nanotubes synthesized by sol-gel with template technique

    SciTech Connect (OSTI)

    Zou, Xuejun [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China)] [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China); Li, Xinyong, E-mail: xyli@dlut.edu.cn [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China) [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China); Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Qu, Zhenping; Zhao, Qidong; Shi, Yong; Chen, Yongying [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China)] [State Key Laboratory of Fine Chemical and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian, 116024 (China); Tade, Moses [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Liu, Shaomin, E-mail: shaomin.liu@curtin.edu.au [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)

    2012-02-15

    Graphical abstract: TiO{sub 2}-SiO{sub 2} nanotubes (b) were fabricated by sol-gel method using ZnO nanowires (a) as template. Highlights: Black-Right-Pointing-Pointer A simple method to prepare TiO{sub 2}-SiO{sub 2} nanotubes for photocatalytic toluene removal. Black-Right-Pointing-Pointer The TiO{sub 2}-SiO{sub 2} nanotubes have a small blue shift and higher absorption intensity. Black-Right-Pointing-Pointer The TiO{sub 2}-SiO{sub 2} nanotubes have an enhanced photoactivity in degrading gaseous toluene. -- Abstract: TiO{sub 2}-SiO{sub 2} composite nanotubes were successfully synthesized by a facile sol-gel technique utilizing ZnO nanowires as template. The nanotubes were well characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, N{sub 2} adsorption-desorption analysis and UV-vis diffuse reflectance spectroscopy. The nanotubular TiO{sub 2}-SiO{sub 2} composite photocatalysts showed diameter of 300-325 nm, fine mesoporous structure and high specific surface area. The results indicated that the degradation efficiency of gaseous toluene could get 65% after 4 h reaction using the TiO{sub 2}-SiO{sub 2} composite as the photocatalyst under UV light illumination, which was higher than that of P25.

  9. Sodium dodecyl benzene sulfonate-assisted synthesis through a hydrothermal reaction

    SciTech Connect (OSTI)

    Sobhani, Azam; Salavati-Niasari, Masoud; Institute of Nano Science and Nano Technology, University of Kashan, Kashan, P.O. Box 87317–51167, Islamic Republic of Iran

    2012-08-15

    Graphical abstract: Reaction of a SeCl{sub 4} aqueous solution with a NiCl{sub 2}·6H{sub 2}O aqueous solution in presence of sodium dodecyl benzene sulfonate (SDBS) as capping agent and hydrazine (N{sub 2}H{sub 4}·H{sub 2}O) as reductant, produces nanosized nickel selenide through a hydrothermal method. The effect of temperature, reaction time and amounts of reductant on the morphology, particle sizes of NiSe nanostructures has been investigated. Highlights: ? NiSe nanostructures were synthesized by hydrothermal method. ? A novel Se source was used to synthesize NiSe. ? SDBS as capping agent plays a crucial role on the morphology of products. ? A mixture of Ni{sub 3}Se{sub 2} and NiSe was prepared in the presence of 2 ml hydrazine. ? A pure phase of NiSe was prepared in the presence of 4 or 6 ml hydrazine. -- Abstract: The effects of the anionic surfactant on the morphology, size and crystallization of NiSe precipitated from NiCl{sub 2}·6H{sub 2}O and SeCl{sub 4} in presence of hydrazine (N{sub 2}H{sub 4}·H{sub 2}O) as reductant were investigated. The products have been successfully synthesized in presence of sodium dodecyl benzene sulfonate (SDBS) as surfactant via an improved hydrothermal route. A variety of synthesis parameters, such as reaction time and temperature, capping agent and amount of reducing agent have a significant effect on the particle size, phase purity and morphology of the obtained products. The sample size became bigger with decreasing reaction temperature and increasing reaction time. In the presence of 2 ml hydrazine, the samples were found to be the mixture of Ni{sub 3}Se{sub 2} and NiSe. With increasing the reaction time and amount of hydrazine a pure phase of hexagonal NiSe was obtained. X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) images indicate phase, particle size and morphology of the products. Chemical composition and purity of the products were characterized by X-ray energy dispersive spectroscopy (EDS). Photoluminescence (PL) was used to study the optical properties of NiSe samples.

  10. A pilot-scale field study on the anaerobic biotreatment of soil impacted with highly chlorinated benzenes

    SciTech Connect (OSTI)

    Ramanand, K.; Foulke, B.; Delnicki, W.A.; Ying, A.C.; Baek, N.H.; Coats, M.L.; Duffy, J.J.

    1995-12-31

    An on-site pilot-scale demonstration of anaerobic biodegradation of highly chlorinated benzenes was successfully performed at a chemical manufacturing industrial facility in Niagara Falls, New York. The field investigation was conducted in 6-yd{sup 3} capacity soil boxes. Approximately 4 yd{sup 3} of soil impacted with chlorinated compounds was placed in each soil box. Chlorinated benzenes with 3 or more chlorines accounted for about 85% of the total chemistry in the soil. The soil box amended with water, nutrients, and acclimated soil microbial inoculum exhibited greater than 78% reduction in the levels of highly chlorinated compounds after one year of field study. The total concentrations of hexa-, penta-, tetra-, and trichlorobenzenes decreased from 920 mg/kg to less than 190 mg/kg, while the total concentrations of di-, and monochlorobenzene increased from 8 mg/kg to greater than 400 mg/kg during one year of field operation. The control soil that did not receive any external nutrient or microbial amendments maintained the same percentage of the highly chlorinated benzenes after one year and di-, and monochlorobenzene never exceeded more than 4 mg/kg at any given time period. The anaerobic activity was further confirmed by monitored parameters such as nutrient consumption (butyrate, nitrogen, organic matter), sulfate depletion, and methane production.

  11. Photocatalytic degradation of gaseous toluene over hollow “spindle-like” ?-Fe{sub 2}O{sub 3} loaded with Ag

    SciTech Connect (OSTI)

    Li, Hong [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China) [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Department of Basic, Dalian Naval Academy, Dalian 116018 (China); Zhao, Qidong [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China)] [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Li, Xinyong, E-mail: xyli@dlut.edu.cn [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China) [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Shi, Yong [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China)] [State Key Laboratory of Fine Chemical, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Zhu, Zhengru [Research Center of Hydrology and Engineering, Academy of City and Environment, Liaoning Normal University, Dalian 116029 (China)] [Research Center of Hydrology and Engineering, Academy of City and Environment, Liaoning Normal University, Dalian 116029 (China); Tade, Moses [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia); Liu, Shaomin, E-mail: shaomin.liu@curtin.edu.au [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University, Perth, WA 6845 (Australia)

    2012-06-15

    Highlights: ? Hollow ?-Fe{sub 2}O{sub 3} spindle-shaped microparticles were prepared for Ag support. ? The hollow ?-Fe{sub 2}O{sub 3} and Ag/?-Fe{sub 2}O{sub 3} materials were used to degrade gaseous toluene. ? Complete degradation of toluene occurred on the Ag/?-Fe{sub 2}O{sub 3} surface. -- Abstract: In this work, hollow “spindle-like” ?-Fe{sub 2}O{sub 3} nanoparticles were synthesized by a hydrothermal route. The Ag/?-Fe{sub 2}O{sub 3} catalyst was prepared based on the spindle-shaped ?-Fe{sub 2}O{sub 3} with CTAB as the surfactant, which showed excellent photoelectric property and photocatalytic activity. The structural properties of these samples were systematically investigated by X-ray powder diffraction, scanning electronic microscopy, transmission electronic microscopy, energy-dispersive X-ray spectra, and UV–Vis diffuse reflectance spectroscopy techniques. The photo-induced charge separation in the samples was demonstrated by surface photovoltage measurement. The photocatalytic performances of the Ag/?-Fe{sub 2}O{sub 3} and ?-Fe{sub 2}O{sub 3} samples were comparatively studied in the degradation of toluene under xenon lamp irradiation by in situ FTIR spectroscopy. Benzaldehyde and benzoic acid species could be observed on the ?-Fe{sub 2}O{sub 3} surface rather than Ag/?-Fe{sub 2}O{sub 3} surface. The results indicate that the Ag/?-Fe{sub 2}O{sub 3} sample exhibited higher photocatalytic efficiency.

  12. Benchmark Theoretical Study of the π–π Binding Energy in the Benzene Dimer

    SciTech Connect (OSTI)

    Miliordos, Evangelos; Apra, Edoardo; Xantheas, Sotiris S.

    2014-09-04

    We establish a new estimate for the interaction energy between two benzene molecules in the parallel displaced (PD) conformation by systematically converging (i) the intra- and intermolecular geometry at the minimum geometry, (ii) the expansion of the orbital basis set and (iii) the level of electron correlation. The calculations were performed at the second order Møller - Plesset perturbation (MP2) and the Coupled Cluster including Singles, Doubles and a perturbative estimate of Triples replacements [CCSD(T)] levels of electronic structure theory. At both levels of theory, by including results corrected for Basis Set Superposition Error (BSSE), we have estimated the Complete Basis Set (CBS) limit by employing the family of Dunning’s correlation consistent polarized valence basis sets. The largest MP2 calculation was performed with the cc-pV6Z basis set (2,772 basis functions), whereas the largest CCSD(T) calculation with the cc-pV5Z basis set (1,752 basis functions). The cluster geometries were optimized with basis sets up to quadruple-ζ quality, observing that both its intra- and inter-molecular parts have practically converged with the triple-ζ quality sets. The use of converged geometries was found to play an important role for obtaining accurate estimates for the CBS limits. Our results demonstrate that the binding energies with the families of the plain (cc-pVnZ) and augmented (aug-cc-pVnZ) sets converge [to within < 0.01 kcal/mol for MP2 and < 0.15 kcal/mol for CCSD(T)] to the same CBS limit. In addition, the average of the uncorrected and BSSEcorrected binding energies was found to converge to the same CBS limit must faster than either of the two constituents (uncorrected or BSSE-corrected binding energies). Due to the fact that the family of augmented basis sets (especially for the larger sets) causes serious linear dependency problems, the plain basis sets (for which no linear dependencies were found) are deemed as a more efficient and straightforward path for obtaining an accurate CBS limit. We considered extrapolations of the uncorrected (Δ𝐸) and BSSE-corrected (Δ𝐸!") binding energies, their average value (Δ𝐸!"#) as well as the average of the latter over the plain and augmented sets (Δ𝐸!"#) with the cardinal number of the basis set n. Our best estimate of the CCSD(T)/CBS limit for the Ï€-Ï€ interaction energy in the PD benzene dimer is De = 2.65 ± 0.02 kcal/mol. The best CCSD(T)/cc-pV5Z calculated value is 2.62 kcal/mol, just 0.03 kcal/mol away from the CBS limit. For comparison, the MP2/CBS limit estimate is 5.00 ± 0.01 kcal/mol, demonstrating a 90% overbinding with respect to CCSD(T). The Spin-Component-Scaled (SCS) MP2 variant was found to closely reproduce the CCSD(T) results for each basis set, while Scaled-Opposite-Spin (SOS) yielded results that are too low when compared to CCSD(T).

  13. Impact of the revised OSHA exposure standard on evaluation and control of benzene and other volatile organic chemicals in the liquid petroleum pipeline industry

    SciTech Connect (OSTI)

    Mercer, D.O.

    1989-01-01

    The primary purpose of this study was to determine the benzene exposure potential of workers in the liquid petroleum pipeline industry and to assess the impact of compliance with the revised standard on this industry. In addition, exposure to ethylene dibromide (EDB), and ethylene dichloride (EDC), which have toxicological profiles similar to that of benzene and are routinely found in this industry, were evaluated and appropriate control protocols were recommended. Exposure potential to benzene in excess of the 0.5 ppm (8-hour TWA) OSHA action level was shown to be limited to three free product handling operations, and that this increased exposure potential was dependent on the length of time necessary to perform the operations. The incidence and magnitude of benzene overexposure was not severe and control could be accomplished with engineering methods, along with work practice controls and personal protective equipment. Through application of a risk assessment model it was shown that 14 excess leukemia deaths per one thousand workers could be expected in the employee population that routinely performs those operation having maximum benzene exposure potential. This compares to less than on excess leukemia death per one thousand workers in the total work population. The evaluation of EDB and EDC indicated that exposure potential to EDB was of greatest concern. Even though exposure could be limited through application of standard industrial hygiene methods, any control protocol short of total elimination of EDB from the product stream may be not sufficient to reduce exposure to accepted levels.

  14. Mobilization and Transport of Organic Compounds from Reservoir Rock and Caprock in Geological Carbon Sequestration Sites

    SciTech Connect (OSTI)

    Zhong, Lirong; Cantrell, Kirk J.; Mitroshkov, Alexandre V.; Shewell, Jesse L.

    2014-05-06

    Supercritical CO2 (scCO2) is an excellent solvent for organic compounds, including benzene, toluene, ethyl-benzene, and xylene (BTEX), phenols, and polycyclic aromatic hydrocarbons (PAHs). Monitoring results from geological carbon sequestration (GCS) field tests has shown that organic compounds are mobilized following CO2 injection. Such results have raised concerns regarding the potential for groundwater contamination by toxic organic compounds mobilized during GCS. Knowledge of the mobilization mechanism of organic compounds and their transport and fate in the subsurface is essential for assessing risks associated with GCS. Extraction tests using scCO2 and methylene chloride (CH2Cl2) were conducted to study the mobilization of volatile organic compounds (VOCs, including BTEX), the PAH naphthalene, and n-alkanes (n-C20 – n-C30) by scCO2 from representative reservoir rock and caprock obtained from depleted oil reservoirs and coal from an enhanced coal-bed methane recovery site. More VOCs and naphthalene were extractable by scCO2 compared to the CH2Cl2 extractions, while scCO2 extractable alkane concentrations were much lower than concentrations extractable by CH2Cl2. In addition, dry scCO2 was found to extract more VOCs than water saturated scCO2, but water saturated scCO2 mobilized more naphthalene than dry scCO2. In sand column experiments, moisture content was found to have an important influence on the transport of the organic compounds. In dry sand columns the majority of the compounds were retained in the column except benzene and toluene. In wet sand columns the mobility of the BTEX was much higher than that of naphthalene. Based upon results determined for the reservoir rock, caprock, and coal samples studied here, the risk to aquifers from contamination by organic compounds appears to be relatively low; however, further work is necessary to fully evaluate risks from depleted oil reservoirs.

  15. Raman Spectroscopy of the Reaction of Thin Films of Solid-State Benzene with Vapor-Deposited Ag, Mg, and Al

    SciTech Connect (OSTI)

    Schalnat, Matthew C.; Hawkridge, Adam M.; Pemberton, Jeanne E.

    2011-07-21

    Thin films of solid-state benzene at 30 K were reacted with small quantities of vapor-deposited Ag, Mg, and Al under ultrahigh vacuum, and products were monitored using surface Raman spectroscopy. Although Ag and Mg produce small amounts of metal–benzene adduct products, the resulting Raman spectra are dominated by surface enhancement of the normal benzene modes from metallic nanoparticles suggesting rapid Ag or Mg metallization of the film. In contrast, large quantities of Al adduct products are observed. Vibrational modes of the products in all three systems suggest adducts that are formed through a pathway initiated by an electron transfer reaction. The difference in reactivity between these metals is ascribed to differences in ionization potential of the metal atoms; ionization potential values for Ag and Mg are similar but larger than that for Al. These studies demonstrate the importance of atomic parameters, such as ionization potential, in solid-state metal–organic reaction chemistry.

  16. Facile preparation of sphere-like copper ferrite nanostructures and their enhanced visible-light-induced photocatalytic conversion of benzene

    SciTech Connect (OSTI)

    Shen, Yu; Wu, Yanbo; Xu, Hongfeng; Fu, Jie; Li, Xinyong; Zhao, Qidong; Hou, Yang

    2013-10-15

    Graphical abstract: - Highlights: • Spinel CuFe{sub 2}O{sub 4} nanospheres were successfully synthesized via a facile method. • CuFe{sub 2}O{sub 4} nanospheres showed high photocatalytic activity toward benzene. • Ethyl acetate, carboxylic acid and aldehyde were the intermediate products. - Abstract: Spinel copper ferrite nanospheres with diameters of about 116 nm were synthesized in high yield via a facile solvothermal route. The prepared nanospheres had cubic spinel structure and exhibited good size uniformity and regularity. The band-gap energy of CuFe{sub 2}O{sub 4} nanospheres was calculated to be about 1.69 eV, indicating their potential visible-light-induced photocatalytic activity. The dramatically enhanced photocatalytic activity of the CuFe{sub 2}O{sub 4} nanospheres was evaluated via the photocatalytic conversion of benzene under Xe lamp irradiation. By using the in situ FTIR technique, ethyl acetate, carboxylic acid and aldehyde could be regarded as the intermediate products, and CO{sub 2} was produced as the final product during the reaction process. This study provided new insight into the design and preparation of functional nanomaterials with sphere structure in high yield, and the as-grown architectures demonstrated an excellent ability to remove organic pollutants in the atmosphere.

  17. A density functional theory study of magneto-electric Jones birefringence of noble gases, furan homologues, and mono-substituted benzenes

    SciTech Connect (OSTI)

    Fahleson, Tobias; Norman, Patrick; Coriani, Sonia; Rizzo, Antonio; Rikken, Geert L. J. A.

    2013-11-21

    We report on the results of a systematic ab initio study of the Jones birefringence of noble gases, of furan homologues, and of monosubstituted benzenes, in the gas phase, with the aim of analyzing the behavior and the trends within a list of systems of varying size and complexity, and of identifying candidates for a combined experimental/theoretical study of the effect. We resort here to analytic linear and nonlinear response functions in the framework of time-dependent density functional theory. A correlation is made between the observable (the Jones constant) and the atomic radius for noble gases, or the permanent electric dipole and a structure/chemical reactivity descriptor as the para Hammett constant for substituted benzenes.

  18. Association of genetic polymorphisms in GADD45A, MDM2, and p14{sup ARF} with the risk of chronic benzene poisoning in a Chinese occupational population

    SciTech Connect (OSTI)

    Sun Pin; Zhang Zhongbin; Wan Junxiang; Zhao Naiqing; Jin Xipeng; Xia Zhaolin

    2009-10-01

    Benzene reactive metabolites can lead to DNA damage and trigger the p53-dependent defense responses to maintain genomic stability. We hypothesized that the p53-dependent genes may play a role in the development of chronic benzene poisoning (CBP). In a case-control study of 303 patients with benzene poisoning and 295 workers occupationally exposed to benzene in south China, we investigated associations between the risk of CBP and polymorphisms in three p53-dependent genes. Potential interactions of these polymorphisms with lifestyle factors were also explored. We found p14{sup ARF} rs3731245 polymorphism was associated with risk of CBP (P = 0.014). Compared with those carrying the GG genotype, individuals carrying p14{sup ARF} rs3731245 GA+AA genotypes had a reduced risk of CBP ([adjusted odds ratio (OR{sub adj}) = 0.57, 95%CI = 0.36-0.89]. Further analysis showed p14{sup ARF} TGA/TAG diplotype was associated with an increased risk of CBP (P = 0.0006), whereas p14{sup ARF} TGG/TAA diplotype was associated with a decreased risk of CBP (P = 0.0000001). In addition, we found individuals carrying both MDM2 Del1518 WW genotype and p14{sup ARF} rs3731245 GA+AA genotypes had a lower risk of CBP (OR{sub adj} = 0.25; 95%CI = 0.10-0.62; P = 0.003). Although these results require confirmation and extension, our findings suggest that genetic polymorphisms in p14{sup ARF} may have an impact on the risk of CBP in the study population.

  19. Characterization Of The Hydrogenation Products Of Bix (phenylethynyl) Benzene (DEB) Getter Using Combined GC/FTIR/MS, FT-Raman, and ATR Spectroscopies (U)

    SciTech Connect (OSTI)

    Smyrl, N. R.; Powell, G. L.

    2011-06-09

    Organic hydrogen getters are utilized to minimize hydrogen accumulation in sealed systems where such build up could produce either a safety problem from pressure build up or corrosion problem due the hydriding of metals contained in the sealed vessel. DEB (1,4 bis (phenyl ethynyl) benzene) is a hydrogen getter that is based on the palladium catalyzed hydrogenation of triple bonds to single bonds in aromatic aryl compound. DEB is a getter mixed with 25% carbon and 1% Pd and pressed into pellets with some porosity. The reaction mechanisms are complex involving solid state reactions with a heterogeneous catalyst leading to the many intermediates.

  20. State-selective laser photoionization of neutral benzene molecules ejected from keV ion bombarded C{sub 6}H{sub 6}/Ag{l_brace}111{r_brace}

    SciTech Connect (OSTI)

    Meserole, C. A.; Vandeweert, E.; Chatterjee, R.; Chakraborty, B. R.; Garrison, B. J.; Winograd, N.; Postawa, Z.

    1998-12-16

    One-color two-photon ionization spectroscopy was used to probe state-selectively neutral benzene molecules desorbed from a benzene overlayer physisorbed on a Ag{l_brace}111{r_brace} surface upon 8 keV Ar{sup +} bombardment. Time distributions were measured for benzene molecules ejected in the zero level of the molecular ground state and in the first state of the {nu}{sub 6} ' vibration. These distributions are found to show a strong dependence both on the internal energy of the ejected molecules and the degree of coverage of the Ag surface. Up to monolayer coverages, benzene molecules are ejected by direct collisions with Ag particles sputtered from the underlying substrate. Molecules with higher internal energy leave the surface with a distribution shifted towards lower flight times. At multilayer coverages, a second, thermal-like ejection mechanism gains significance. It is suggested that only molecules excited near the benzene-vacuum interface, survive the ejection process without being deexcited.

  1. FTIR study of the photocatalytic degradation of gaseous benzene over UV-irradiated TiO{sub 2} nanoballs synthesized by hydrothermal treatment in alkaline solution

    SciTech Connect (OSTI)

    Zhu, Zhengru [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian 116024 (China)] [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian 116024 (China); Li, Xinyong, E-mail: xyli@dlut.edu.cn [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian 116024 (China)] [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian 116024 (China); Zhao, Qidong; Qu, Zhenping; Hou, Yang; Zhao, Ling [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian 116024 (China)] [Key Laboratory of Industrial Ecology and Environmental Engineering and State Key Laboratory of Fine Chemical, School of Environmental Sciences and Technology, Dalian University of Technology, Dalian 116024 (China); Liu, Shaomin [Department of Chemical Engineering, Curtin University of Technology, Perth, WA 6845 (Australia)] [Department of Chemical Engineering, Curtin University of Technology, Perth, WA 6845 (Australia); Chen, Guohua [Department of Chemical and Biomolecular Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)] [Department of Chemical and Biomolecular Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

    2010-12-15

    In this study, photocatalysts of TiO{sub 2} nanoballs were obtained via a hydrothermal treating of commercial P25 in alkaline solution, and then characterized with SEM, XRD, BET and surface photovoltage spectroscopy techniques. The UV-assisted photodegradation of gaseous benzene over P25 and the prepared TiO{sub 2} nanoballs was monitored by an in situ infrared technique. The results demonstrated that the prepared TiO{sub 2} nanoballs in anatase form were more active than commercial P25 in photocatalytic oxidation of gaseous benzene. The promoted activity of the hydrothermal-treated TiO{sub 2} is attributed to the increasing specific surface area and larger band gap induced by the reduced crystallite size. The spectra of FTIR indicated that weakly adsorbed phenol was formed as the reaction progress. Hydroxyl groups on the surface of TiO{sub 2} nanoballs are able to react with photo-produced phenol, which is then retained on the catalyst surface leading to the progressive deactivation of the catalyst in the gas-solid system.

  2. Water on BN doped benzene: A hard test for exchange-correlation functionals and the impact of exact exchange on weak binding

    SciTech Connect (OSTI)

    Al-Hamdani, Yasmine S.; Alfè, Dario; von Lilienfeld, O. Anatole; Michaelides, Angelos

    2014-10-22

    Density functional theory (DFT) studies of weakly interacting complexes have recently focused on the importance of van der Waals dispersion forces, whereas the role of exchange has received far less attention. Here, by exploiting the subtle binding between water and a boron and nitrogen doped benzene derivative (1,2-azaborine) we show how exact exchange can alter the binding conformation within a complex. Benchmark values have been calculated for three orientations of the water monomer on 1,2-azaborine from explicitly correlated quantum chemical methods, and we have also used diffusion quantum Monte Carlo. For a host of popular DFT exchange-correlation functionals we show that the lack of exact exchange leads to the wrong lowest energy orientation of water on 1,2-azaborine. As such, we suggest that a high proportion of exact exchange and the associated improvement in the electronic structure could be needed for the accurate prediction of physisorption sites on doped surfaces and in complex organic molecules. Meanwhile to predict correct absolute interaction energies an accurate description of exchange needs to be augmented by dispersion inclusive functionals, and certain non-local van der Waals functionals (optB88- and optB86b-vdW) perform very well for absolute interaction energies. Through a comparison with water on benzene and borazine (B?N?H?) we show that these results could have implications for the interaction of water with doped graphene surfaces, and suggest a possible way of tuning the interaction energy.

  3. Assessing electronic structure approaches for gas-ligand interactions in metal-organic frameworks: The CO{sub 2}-benzene complex

    SciTech Connect (OSTI)

    Witte, Jonathon; Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720 ; Neaton, Jeffrey B.; Head-Gordon, Martin; Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720

    2014-03-14

    Adsorption of gas molecules in metal-organic frameworks is governed by many factors, the most dominant of which are the interaction of the gas with open metal sites, and the interaction of the gas with the ligands. Herein, we examine the latter class of interaction in the context of CO{sub 2} binding to benzene. We begin by clarifying the geometry of the CO{sub 2}–benzene complex. We then generate a benchmark binding curve using a coupled-cluster approach with single, double, and perturbative triple excitations [CCSD(T)] at the complete basis set (CBS) limit. Against this ?CCSD(T)/CBS standard, we evaluate a plethora of electronic structure approximations: Hartree-Fock, second-order Møller-Plesset perturbation theory (MP2) with the resolution-of-the-identity approximation, attenuated MP2, and a number of density functionals with and without different empirical and nonempirical van der Waals corrections. We find that finite-basis MP2 significantly overbinds the complex. On the other hand, even the simplest empirical correction to standard density functionals is sufficient to bring the binding energies to well within 1 kJ/mol of the benchmark, corresponding to an error of less than 10%; PBE-D in particular performs well. Methods that explicitly include nonlocal correlation kernels, such as VV10, vdW-DF2, and ?B97X-V, perform with similar accuracy for this system, as do ?B97X and M06-L.

  4. Correlating Extent of Pt–Ni Bond Formation with Low-temperature Hydrogenation of Benzene and 1,3-butadiene over Supported Pt/Ni Bimetallic Catalysts

    SciTech Connect (OSTI)

    Lonergan, W.; Vlachos, D; Chen, J

    2010-01-01

    Low-temperature hydrogenation of benzene and 1,3-butadiene on supported Pt/Ni catalysts have been used as probe reactions to correlate hydrogenation activity with the extent of Pt-Ni bimetallic bond formation. Pt/Ni bimetallic and Pt and Ni monometallic catalysts were supported on {gamma}-Al{sub 2}O{sub 3} using incipient wetness impregnation. Two sets of bimetallic catalysts were synthesized: one set to study the effect of metal atomic ratio and the other to study the effect of impregnation sequence. Fourier transform infrared spectroscopy (FTIR) CO adsorption studies were performed to characterize the surface composition of the bimetallic nanoparticles, and transmission electron microscopy (TEM) was utilized to characterize the particle size distribution. Batch reactor studies with FTIR demonstrated that all bimetallic catalysts outperformed monometallic catalysts for both benzene and 1,3-butadiene hydrogenation. Within the two sets of bimetallic catalysts, it was found that catalysts with a smaller Pt:Ni ratio possessed higher hydrogenation activity and that catalysts synthesized using co-impregnation had greater activity than sequentially impregnated catalysts. Extended X-ray absorption fine structure (EXAFS) measurements were performed in order to verify the extent of Pt-Ni bimetallic bond formation, which was found to correlate with the hydrogenation activity.

  5. Trip Report-Produced-Water Field Testing

    SciTech Connect (OSTI)

    Sullivan, Enid J.

    2012-05-25

    Los Alamos National Laboratory (LANL) conducted field testing of a produced-water pretreatment apparatus with assistance from faculty at the Texas A&M University (TAMU) protein separation sciences laboratory located on the TAMU main campus. The following report details all of the logistics surrounding the testing. The purpose of the test was to use a new, commercially-available filter media housing containing modified zeolite (surfactant-modified zeolite or SMZ) porous medium for use in pretreatment of oil and gas produced water (PW) and frac-flowback waters. The SMZ was tested previously in October, 2010 in a lab-constructed configuration ('old multicolumn system'), and performed well for removal of benzene, toluene, ethylbenzene, and xylenes (BTEX) from PW. However, a less-expensive, modular configuration is needed for field use. A modular system will allow the field operator to add or subtract SMZ filters as needed to accommodate site specific conditions, and to swap out used filters easily in a multi-unit system. This test demonstrated the use of a commercial filter housing with a simple flow modification and packed with SMZ for removing BTEX from a PW source in College Station, Texas. The system will be tested in June 2012 at a field site in Pennsylvania for treating frac-flowback waters. The goals of this test are: (1) to determine sorption efficiency of BTEX in the new configuration; and (2) to observe the range of flow rates, backpressures, and total volume treated at a given flow rate.

  6. Superfund Record of Decision (EPA Region 3): Rhinehart Tire Fire Dump, Operable Unit 2, Winchester, VA. (Second remedial action), September 1992

    SciTech Connect (OSTI)

    Not Available

    1992-09-29

    The Rhinehart Tire Fire Dump site is located in a 22-acre drainage area of a sparsely populated rural area in western Frederick County, Virginia. Surface water runoff flows into a north-south tributary that discharges to Hogue Creek, which is 4,000 feet downstream. Bedrock is noted to be highly fractured, and the ground water flow in the overburden aquifer is toward Massey Run. From 1972 to 1983, the site owner conducted a tire disposal operation, which consisted of transporting discarded tires from various locations and storing them on a 5-acre wooded slope behind his home. An estimated 5 to 7 million tires that had been accumulated caught on fire in October 1983 and burned until July 1984. As a result of the fire, a free-flowing oily-tar, which contained anthracene, benzene, cadmium, chromium, ethylbenzene, napthalene, nickel, pyrene, toluene, and zinc, began to seep out of the tire pile into Massey Run and on to Hogue Creek.

  7. Surface acoustic wave sensors/gas chromatography; and Low quality natural gas sulfur removal and recovery CNG Claus sulfur recovery process

    SciTech Connect (OSTI)

    Klint, B.W.; Dale, P.R.; Stephenson, C.

    1997-12-01

    This topical report consists of the two titled projects. Surface Acoustic Wave/Gas Chromatography (SAW/GC) provides a cost-effective system for collecting real-time field screening data for characterization of vapor streams contaminated with volatile organic compounds (VOCs). The Model 4100 can be used in a field screening mode to produce chromatograms in 10 seconds. This capability will allow a project manager to make immediate decisions and to avoid the long delays and high costs associated with analysis by off-site analytical laboratories. The Model 4100 is currently under evaluation by the California Environmental Protection Agency Technology Certification Program. Initial certification focuses upon the following organics: cis-dichloroethylene, chloroform, carbon tetrachloride, trichlorethylene, tetrachloroethylene, tetrachloroethane, benzene, ethylbenzene, toluene, and o-xylene. In the second study the CNG Claus process is being evaluated for conversion and recovery of elemental sulfur from hydrogen sulfide, especially found in low quality natural gas. This report describes the design, construction and operation of a pilot scale plant built to demonstrate the technical feasibility of the integrated CNG Claus process.

  8. Risk-based approach for bioremediation of fuel hydrocarbons at a major airport

    SciTech Connect (OSTI)

    Wiedemeier, T.H.; Guest, P.R.; Blicker, B.R.

    1994-12-31

    This paper describes a risk-based approach for bioremediation of fuel-hydrocarbon-contaminated soil and ground water at a major airport in Colorado. In situ bioremediation pilot testing, natural attenuation modeling, and full-scale remedial action planning and implementation for soil and ground water contamination has conducted at four airport fuel farms. The sources of fuel contamination were leaking underground storage tanks (USTs) or pipelines transporting Jet A fuel and aviation gasoline. Continuing sources of contamination were present in several small cells of free-phase product and in fuel residuals trapped within the capillary fringe at depths 15 to 20 feet below ground surface. Bioventing pilot tests were conducted to assess the feasibility of using this technology to remediate contaminated soils. The pilot tests included measurement of initial soil gas chemistry at the site, determination of subsurface permeability, and in situ respiration tests to determine fuel biodegradation rates. A product recovery test was also conducted. ES designed and installed four full-scale bioventing systems to remediate the long-term sources of continuing fuel contamination. Benzene, toluene, ethylbenzene, and xylenes (BTEX) and total petroleum hydrocarbons (TPH) were detected in ground water at concentrations slightly above regulatory guidelines.

  9. Operable Unit 1 remedial investigation report, Eielson Air Force Base, Alaska

    SciTech Connect (OSTI)

    Gilmore, T.J.; Fruland, R.M.; Liikala, T.L.

    1994-06-01

    This remedial investigation report for operable Unit 1 (OU-1) at Eielson Air Force Base presents data, calculations, and conclusions as to the nature and extent of surface and subsurface contamination at the eight source areas that make up OU-1. The information is based on the 1993 field investigation result and previous investigations. This report is the first in a set of three for OU-1. The other reports are the baseline risk assessment and feasibility study. The information in these reports will lead to a Record of Decision that will guide and conclude the environmental restoration effort for OU-1 at Eielson Air Force Base. The primary contaminants of concern include fuels and fuel-related contaminants (diesel; benzene, toluene, ethylbenzene, and xylene; total petroleum hydrocarbon; polycyclic aromatic hydrocarbons), maintenance-related solvents and cleaners (volatile chlorinated hydrocarbons such as trichloroothylene), polychlorinated biphenyls, and dichlorodiphenyltrichloroethane (DDT). The origins of contaminants of concern include leaks from storage tanks, drums and piping, and spills. Ongoing operations and past sitewide practices also contribute to contaminants of concern at OU-1 source areas. These include spraying mixed oil and solvent wastes on unpaved roads and aerial spraying of DDT.

  10. Synthesis and characterization of d{sup 10} metal complexes with mixed 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate ligands

    SciTech Connect (OSTI)

    Chen, Zhi-Hao; Zhao, Yue; Chen, Shui-Sheng; Wang, Peng; Sun, Wei-Yin

    2013-06-15

    Seven new coordination polymers [Zn(H{sub 2}L)(mbdc)] (1), [Zn(H{sub 3}L)(btc)] (2), [Zn(H{sub 2}L)(Hbtc)] (3), [Zn(H{sub 2}L)(Hbtc)]·H{sub 2}O (4), [Zn{sub 2}(H{sub 2}L)(btc)(?{sub 2}-OH)] (5), [Cd(H{sub 2}L)(mbdc)] (6) and [Cd{sub 3}(H{sub 2}L){sub 2}(btc){sub 2}(H{sub 2}O)]·5H{sub 2}O (7) were synthesized by reactions of the corresponding metal salt with rigid ligand 1,3-di(1H-imidazol-4-yl)benzene (H{sub 2}L) and different carboxylic acids of 1,3-benzenedicarboxylic acid (H{sub 2}mbdc) and benzene-1,3,5-tricarboxylic acid (H{sub 3}btc), respectively. The results of X-ray crystallographic analysis indicate that complex 1 is 1D chain while 2 is a (3,3)-connected 2D network with Point (Schläfli) symbol of (4,8{sup 2}). Complexes 3 and 6 are 2D networks, 4 is a 3-fold interpenetrating 3D framework with Point (Schläfli) symbol of (6{sup 5},8) and 5 is a (3,8)-connected 2D network with Point (Schläfli) symbol of (3,4{sup 2}){sub 2}(3{sup 4},4{sup 6},5{sup 6},6{sup 8},7{sup 3},8), while 7 is a (3,10)-connected 3D net with Schläfli symbol of (3,4,5){sub 2}(3{sup 4},4{sup 8},5{sup 18},6{sup 12},7{sup 2},8). The thermal stability and photoluminescence of the complexes were investigated. Furthermore, DFT calculations were performed for 2–4 to discuss the temperature controlled self-assembly of the complexes. - Graphical abstract: Seven new coordination polymers with multicarboxylate and rigid ditopic 4-imidazole containing ligands have been obtained and found to show different structures and topologies. - Highlights: • Metal complexes with diverse structures of 1D chain, 2D network and 3D framework. • Mixed ligands of 1,3-di(1H-imidazol-4-yl)benzene and multicarboxylate. • Photoluminescence property.

  11. The oxidation of a gasoline surrogate in the negative temperature coefficient region

    SciTech Connect (OSTI)

    Lenhert, David B.; Miller, David L.; Cernansky, Nicholas P.; Owens, Kevin G.

    2009-03-15

    This experimental study investigated the preignition reactivity behavior of a gasoline surrogate in a pressurized flow reactor over the low and intermediate temperature regime (600-800 K) at elevated pressure (8 atm). The surrogate mixture, a volumetric blend of 4.6% 1-pentene, 31.8% toluene, 14.0% n-heptane, and 49.6% 2,2,4-trimethyl-pentane (iso-octane), was shown to reproduce the low and intermediate temperature reactivity of full boiling range fuels in a previous study. Each of the surrogate components were examined individually to identify the major intermediate species in order to improve existing kinetic models, where appropriate, and to provide a basis for examining constituent interactions in the surrogate mixture. n-Heptane and 1-pentene started reacting at 630 K and 640 K, respectively, and both fuels exhibited a strong negative temperature coefficient (NTC) behavior starting at 700 and 710 K, respectively. Iso-octane showed a small level of reactivity at 630 K and a weak NTC behavior starting at 665 K. Neat toluene was unreactive at these temperatures. The surrogate started reacting at 630 K and exhibited a strong NTC behavior starting at 693 K. The extent of fuel consumption varied for each of the surrogate constituents and was related to their general autoignition behavior. Most of the intermediates identified during the surrogate oxidation were species observed during the oxidation of the neat constituents; however, the surrogate mixture did exhibit a significant increase in intermediates associated with iso-octane oxidation, but not from n-heptane. While neat toluene was unreactive at these temperatures, in the mixture it reacted with the radical pool generated by the other surrogate components, forming benzaldehyde, benzene, phenol, and ethyl-benzene. The observed n-heptane, iso-octane, and surrogate oxidation behavior was compared to predictions using existing kinetic models. The n-heptane model reasonably predicted the disappearance of the fuel, but overpredicted the formation of several of the smaller intermediates. The iso-octane model significantly overpredicted the reaction of the fuel and formation of the intermediates. The 1-pentene model reasonably predicted the fuel consumption, but underestimated the importance of radical addition to the double bond. The results of this study provide a critical experimental foundation for the investigation of surrogate mixtures and for validation of kinetic models. (author)

  12. Benzene analogues of (quasi-)planar M@B{sub n}H{sub n} compounds (M = V{sup ?}, Cr, Mn{sup +}): A theoretical investigation

    SciTech Connect (OSTI)

    Li, Lifen; Xu, Chang; Jin, Baokang; Cheng, Longjiu

    2013-11-07

    The stability of M@B{sub n}H{sub n} (M = V{sup ?}, Cr, Mn{sup +}; n = 5–8) is investigated by density functional theory. For n = 6–8, the isomers possess (quasi-)planar local minima showed by geometry optimization at TPSSh/6-311+G{sup **} level. All the optimized structures are thermodynamics stable according to the large HOMO-LUMO gap, binding energy, vertical ionization potential, and vertical electron affinity analysis. The peripheral and central atomic radius fit each other best at n = 7 confirmed by the variation of the binding energy values. The availability of d atom orbitals in M for participation in the ?-delocalized bonding with the peripheral ring leads to the aromaticity of the (quasi-)planar structures and makes them the benzene analogues. This work establishes firmly the metal-doped borane rings as a new type of aromatic molecule.

  13. Water on BN doped benzene: A hard test for exchange-correlation functionals and the impact of exact exchange on weak binding

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Al-Hamdani, Yasmine S.; Alfè, Dario; von Lilienfeld, O. Anatole; Michaelides, Angelos

    2014-10-22

    Density functional theory (DFT) studies of weakly interacting complexes have recently focused on the importance of van der Waals dispersion forces, whereas the role of exchange has received far less attention. Here, by exploiting the subtle binding between water and a boron and nitrogen doped benzene derivative (1,2-azaborine) we show how exact exchange can alter the binding conformation within a complex. Benchmark values have been calculated for three orientations of the water monomer on 1,2-azaborine from explicitly correlated quantum chemical methods, and we have also used diffusion quantum Monte Carlo. For a host of popular DFT exchange-correlation functionals we showmore » that the lack of exact exchange leads to the wrong lowest energy orientation of water on 1,2-azaborine. As such, we suggest that a high proportion of exact exchange and the associated improvement in the electronic structure could be needed for the accurate prediction of physisorption sites on doped surfaces and in complex organic molecules. Meanwhile to predict correct absolute interaction energies an accurate description of exchange needs to be augmented by dispersion inclusive functionals, and certain non-local van der Waals functionals (optB88- and optB86b-vdW) perform very well for absolute interaction energies. Through a comparison with water on benzene and borazine (B₃N₃H₆) we show that these results could have implications for the interaction of water with doped graphene surfaces, and suggest a possible way of tuning the interaction energy.« less

  14. Water on BN doped benzene: A hard test for exchange-correlation functionals and the impact of exact exchange on weak binding

    SciTech Connect (OSTI)

    Al-Hamdani, Yasmine S.; Michaelides, Angelos; Alfè, Dario; Lilienfeld, O. Anatole von

    2014-11-14

    Density functional theory (DFT) studies of weakly interacting complexes have recently focused on the importance of van der Waals dispersion forces, whereas the role of exchange has received far less attention. Here, by exploiting the subtle binding between water and a boron and nitrogen doped benzene derivative (1,2-azaborine) we show how exact exchange can alter the binding conformation within a complex. Benchmark values have been calculated for three orientations of the water monomer on 1,2-azaborine from explicitly correlated quantum chemical methods, and we have also used diffusion quantum Monte Carlo. For a host of popular DFT exchange-correlation functionals we show that the lack of exact exchange leads to the wrong lowest energy orientation of water on 1,2-azaborine. As such, we suggest that a high proportion of exact exchange and the associated improvement in the electronic structure could be needed for the accurate prediction of physisorption sites on doped surfaces and in complex organic molecules. Meanwhile to predict correct absolute interaction energies an accurate description of exchange needs to be augmented by dispersion inclusive functionals, and certain non-local van der Waals functionals (optB88- and optB86b-vdW) perform very well for absolute interaction energies. Through a comparison with water on benzene and borazine (B{sub 3}N{sub 3}H{sub 6}) we show that these results could have implications for the interaction of water with doped graphene surfaces, and suggest a possible way of tuning the interaction energy.

  15. Quantum effects and anharmonicity in the H{sub 2}-Li{sup +}-benzene complex: A model for hydrogen storage materials

    SciTech Connect (OSTI)

    Kolmann, Stephen J.; D'Arcy, Jordan H.; Jordan, Meredith J. T.

    2013-12-21

    Quantum and anharmonic effects are investigated in H{sub 2}-Li{sup +}-benzene, a model for hydrogen adsorption in metal-organic frameworks and carbon-based materials. Three- and 8-dimensional quantum diffusion Monte Carlo (QDMC) and rigid-body diffusion Monte Carlo (RBDMC) simulations are performed on potential energy surfaces interpolated from electronic structure calculations at the M05-2X/6-31+G(d,p) and M05-2X/6-311+G(2df,p) levels of theory using a three-dimensional spline or a modified Shepard interpolation. These calculations investigate the intermolecular interactions in this system, with three- and 8-dimensional 0 K H{sub 2} binding enthalpy estimates, ?H{sub bind} (0 K), being 16.5 kJ mol{sup ?1} and 12.4 kJ mol{sup ?1}, respectively: 0.1 and 0.6 kJ mol{sup ?1} higher than harmonic values. Zero-point energy effects are 35% of the value of ?H{sub bind} (0 K) at M05-2X/6-311+G(2df,p) and cannot be neglected; uncorrected electronic binding energies overestimate ?H{sub bind} (0 K) by at least 6 kJ mol{sup ?1}. Harmonic intermolecular binding enthalpies can be corrected by treating the H{sub 2} “helicopter” and “ferris wheel” rotations as free and hindered rotations, respectively. These simple corrections yield results within 2% of the 8-dimensional anharmonic calculations. Nuclear ground state probability density histograms obtained from the QDMC and RBDMC simulations indicate the H{sub 2} molecule is delocalized above the Li{sup +}-benzene system at 0 K.

  16. Absorption of ethanol, acetone, benzene and 1,2-dichloroethane through human skin in vitro: a test of diffusion model predictions

    SciTech Connect (OSTI)

    Gajjar, Rachna M.; Kasting, Gerald B.

    2014-11-15

    The overall goal of this research was to further develop and improve an existing skin diffusion model by experimentally confirming the predicted absorption rates of topically-applied volatile organic compounds (VOCs) based on their physicochemical properties, the skin surface temperature, and the wind velocity. In vitro human skin permeation of two hydrophilic solvents (acetone and ethanol) and two lipophilic solvents (benzene and 1,2-dichloroethane) was studied in Franz cells placed in a fume hood. Four doses of each {sup 14}C-radiolabed compound were tested — 5, 10, 20, and 40 μL cm{sup −2}, corresponding to specific doses ranging in mass from 5.0 to 63 mg cm{sup −2}. The maximum percentage of radiolabel absorbed into the receptor solutions for all test conditions was 0.3%. Although the absolute absorption of each solvent increased with dose, percentage absorption decreased. This decrease was consistent with the concept of a stratum corneum deposition region, which traps small amounts of solvent in the upper skin layers, decreasing the evaporation rate. The diffusion model satisfactorily described the cumulative absorption of ethanol; however, values for the other VOCs were underpredicted in a manner related to their ability to disrupt or solubilize skin lipids. In order to more closely describe the permeation data, significant increases in the stratum corneum/water partition coefficients, K{sub sc}, and modest changes to the diffusion coefficients, D{sub sc}, were required. The analysis provided strong evidence for both skin swelling and barrier disruption by VOCs, even by the minute amounts absorbed under these in vitro test conditions. - Highlights: • Human skin absorption of small doses of VOCs was measured in vitro in a fume hood. • The VOCs tested were ethanol, acetone, benzene and 1,2-dichloroethane. • Fraction of dose absorbed for all compounds at all doses tested was less than 0.3%. • The more aggressive VOCs absorbed at higher levels than diffusion model predictions. • We conclude that even small exposures to VOCs temporarily alter skin permeability.

  17. A case report of motor neuron disease in a patient showing significant level of DDTs, HCHs and organophosphate metabolites in hair as well as levels of hexane and toluene in blood

    SciTech Connect (OSTI)

    Kanavouras, Konstantinos; Tzatzarakis, Manolis N.; Mastorodemos, Vasileios; Plaitakis, Andreas; Tsatsakis, Aristidis M.

    2011-11-15

    Motor neuron disease is a devastating neurodegenerative condition, with the majority of sporadic, non-familial cases being of unknown etiology. Several epidemiological studies have suggested that occupational exposure to chemicals may be associated with disease pathogenesis. We report the case of a patient developing progressive motor neuron disease, who was chronically exposed to pesticides and organic solvents. The patient presented with leg spasticity and developed gradually clinical signs suggestive of amyotrophic lateral sclerosis, which was supported by the neurophysiologic and radiological findings. Our report is an evidence based case of combined exposure to organochlorine (DDTs), organophosphate pesticides (OPs) and organic solvents as confirmed by laboratory analysis in samples of blood and hair confirming systematic exposure. The concentration of non-specific dialkylphosphates metabolites (DAPs) of OPs in hair (dimethyphopshate (DMP) 1289.4 pg/mg and diethylphosphate (DEP) 709.4 pg/mg) and of DDTs (opDDE 484.0 pg/mg, ppDDE 526.6 pg/mg, opDDD 448.4 pg/mg, ppDDD + opDDT 259.9 pg/mg and ppDDT 573.7 pg/mg) were considerably significant. Toluene and n-hexane were also detected in blood on admission at hospital and quantified (1.23 and 0.87 {mu}g/l, respectively), while 3 months after hospitalization blood testing was found negative for toluene and n-hexane and hair analysis was provided decrease levels of HCHs, DDTs and DAPs. -- Highlights: Black-Right-Pointing-Pointer Exposure to pesticides and organic solvents might be a risk factor for sporadic MND. Black-Right-Pointing-Pointer We report a patient who developed progressive upper and lower motor neuron disease. Black-Right-Pointing-Pointer The patient had a history of occupational exposure to pesticides and solvents. Black-Right-Pointing-Pointer High DDTs' levels and increased levels of DMP and DEP were measured in his hair. Black-Right-Pointing-Pointer The patients' exposure to chemicals might have played a role in MND development.

  18. Ultra-low-temperature reactions of C({sup 3}P{sub 0}) atoms with benzene molecules in helium droplets

    SciTech Connect (OSTI)

    Krasnokutski, Serge A. Huisken, Friedrich

    2014-12-07

    The reaction of carbon atoms with benzene has been investigated in liquid helium droplets at T = 0.37 K. We found an addition of the carbon atom to form an initial intermediate complex followed by a ring opening and the formation of a seven-membered ring. In contrast to a previous gas phase study, the reaction is frozen after these steps and the loss of hydrogen does not occur. A calorimetric technique was applied to monitor the energy balance of the reaction. It was found that more than 267 kJ mol{sup ?1} were released in this reaction. This estimation is in line with quantum chemical calculations of the formation energy of a seven-membered carbon ring. It is suggested that reactions of this kind could be responsible for the low abundance of small polycyclic aromatic hydrocarbon molecules in the interstellar medium. We also found the formation of weakly bonded water-carbon adducts, in which the carbon atom is linked to the oxygen atom of the water molecule with a binding energy of about 33.4 kJ mol{sup ?1}.

  19. Treatment of Produced Water Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System

    SciTech Connect (OSTI)

    Lynn E. Katz; Kerry A. Kinney; Robert S. Bowman; Enid J. Sullivan; Soondong Kwon; Elaine B. Darby; Li-Jung Chen; Craig R. Altare

    2006-01-31

    Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. Produced waters typically contain a high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component as well as chemicals added during the oil-production process. It has been estimated that a total of 14 billion barrels of produced water were generated in 2002 from onshore operations (Veil, 2004). Although much of this produced water is disposed via reinjection, environmental and cost considerations can make surface discharge of this water a more practical means of disposal. In addition, reinjection is not always a feasible option because of geographic, economic, or regulatory considerations. In these situations, it may be desirable, and often necessary from a regulatory viewpoint, to treat produced water before discharge. It may also be feasible to treat waters that slightly exceed regulatory limits for re-use in arid or drought-prone areas, rather than losing them to reinjection. A previous project conducted under DOE Contract DE-AC26-99BC15221 demonstrated that surfactant modified zeolite (SMZ) represents a potential treatment technology for produced water containing BTEX. Laboratory and field experiments suggest that: (1) sorption of benzene, toluene, ethylbenzene and xylenes (BTEX) to SMZ follows linear isotherms in which sorption increases with increasing solute hydrophobicity; (2) the presence of high salt concentrations substantially increases the capacity of the SMZ for BTEX; (3) competitive sorption among the BTEX compounds is negligible; and, (4) complete recovery of the SMZ sorption capacity for BTEX can be achieved by air sparging the SMZ. This report summarizes research for a follow on project to optimize the regeneration process for multiple sorption/regeneration cycles, and to develop and incorporate a vapor phase bioreactor (VPB) system for treatment of the off-gas generated during air sparging. To this end, we conducted batch and column laboratory SMZ and VPB experiments with synthetic and actual produced waters. Based on the results of the laboratory testing, a pilot scale study was designed and conducted to evaluate the combined SMZ/VPB process. An economic and regulatory feasibility analysis was also completed as part of the current study to assess the viability of the process for various water re-use options.

  20. Modeling of 1,3-hexadiene, 2,4-hexadiene and 1,4-hexadiene-doped methane flames: Flame modeling, benzene and styrene formation

    SciTech Connect (OSTI)

    Sharma, Sandeep; Harper, Michael R.; Green, William H.

    2010-07-15

    In this work, we have developed a detailed chemical kinetic model and reacting flow simulation for the hexadiene-doped 2-d methane diffusion flames studied experimentally by McEnally and Pfefferle. The GRI-Mech 2.11 methane oxidation and Lawrence Livermore butane oxidation mechanisms were used as the base mechanism to which hexadiene chemistry generated by Reaction Mechanism Generator (RMG) was added. Some important chemically activated pathways leading to aromatic species formation, including the reactions on C{sub 5}H{sub 7}, C{sub 6}H{sub 10}, C{sub 6}H{sub 9}, C{sub 6}H{sub 7}, C{sub 8}H{sub 8} and C{sub 8}H{sub 9} potential energy surfaces, are examined in great detail using quantum chemistry (CBS-QB3) and master equation analysis as implemented in Variflex. An efficient program to solve the doped methane diffusion flame was developed. The solver uses the method of lines to solve the species mass balance equation arising in the diffusion flame. It assumes that the temperature and velocity profiles of the doped flame are the same as those of the undoped flame. The mole fractions of various species as predicted by our model are compared to the experimentally measured mole fractions. The agreement between theory and experiments is quite good for most molecules. The added hexadiene dopants to the flame decompose to produce significant amount of cyclopentadienyl radical, which combines with methyl radical to produce benzene. We also show that styrene is formed primarily by recombination of cyclopentadienyl and propargyl radicals, a pathway which to our knowledge, has not been included in prior flame simulations. (author)

  1. Biomass Burning Observation Project (BBOP) Final Campaign Report

    Office of Scientific and Technical Information (OSTI)

    ... proceed by OH + NO2 as the change in the toluene-to-benzene ... ARM Atmospheric Radiation Measurement ASR Atmospheric System ...nitroaromatics: a class of organics that are known ...

  2. Assessment and remediation at former manufactured gas plants

    SciTech Connect (OSTI)

    Mehan, D.G.

    1995-12-01

    Over 1,000 former Manufactured Gas Plants (MGP) have been identified in the United States. Gal Plants were used to produce gas for lighting and heating from coal and oil from the mid-1800s until the 1950s. Former MGP sites are typically impacted by a variety of compounds that do not collectively lend themselves to {open_quotes}standard{close_quotes} assessment and remedial solutions. These compounds include the volatile organic compounds (VOCs) benzene, toluene, ethylbenzene, and xylene, a variety of semi-volatile organic compound, and inorganic compounds (iron and cyanide). The assessment of former MGP sites is complicated because many former sites are now located in developed and industrialized areas. MGP wastes and by-products were typically disposed on-site. Many modern buildings are now located over former MGP sites. Standard assessment tools such as augering and drilling tend to encounter former structures, making their use difficult and ineffective. Assessment by excavation and geophysical methods allows the acquisition of only shallow data. The remediation of impacted soils and ground water at former MGP sites poses significant challenges due to the differing characteristics of the typical MGP compounds. For example, soil vapor extraction and ground water treatment may decrease VOC concentrations, yet be ineffective on the inorganic and PAH compounds. Because of the variety of typical MGP associated wastes, risk assessment is a vital tool in assessing and selecting the appropriate remedial strategies. Several states have aggressively adopted clean-up programs that rely on risk assessment to determine the appropriate remedial strategy at former MGP sites. At numerous sites, no further action is employed because of the VOCs have attenuated over time, the PAH and inorganic compounds are relatively immobile, ground water contamination plumes are limited, and risk assessment indicates acceptable risks.

  3. A lean methane premixed laminar flame doped with components of diesel fuel part III: Indane and comparison between n-butylbenzene, n-propylcyclohexane and indane

    SciTech Connect (OSTI)

    Pousse, E.; Tian, Z.Y.; Glaude, P.A.; Fournet, R.; Battin-Leclerc, F. [Laboratoire des Reactions et de Genie des Procedes, CNRS, Nancy Universite, 1 rue Grandville, BP 20451, 54001 NANCY Cedex (France)

    2010-07-15

    To better understand the chemistry of the combustion of components of diesel fuel, the structure of a laminar lean premixed methane flame doped with indane has been investigated. The inlet gases contained 7.1% (molar) of methane, 36.8% of oxygen and 0.9% of indane corresponding to an equivalence ratio of 0.67 and a ratio C{sub 10}H{sub 14}/CH{sub 4} of 12.8%. The flame has been stabilized on a burner at a pressure of 6.7 kPa (50 Torr) using argon as diluent, with a gas velocity at the burner of 49.1 cm s{sup -1} at 333 K. Quantified species included the usual methane C{sub 0}-C{sub 2} combustion products, but also 16 C{sub 3}-C{sub 5} non-aromatic hydrocarbons, 6 C{sub 1}-C{sub 3} non-aromatic oxygenated compounds, as well as 22 aromatic products, namely benzene, toluene, xylenes, phenylacetylene, ethylbenzene, styrene, propenylbenzene, allylbenzene, n-propylbenzene, methylstyrenes, ethyltoluenes, trimethylbenzenes, n-butylbenzene, dimethylethylbenzene, indene, methylindenes, methylindane, benzocyclobutene, naphthalene, phenol, benzaldehyde, and benzofuran. A new mechanism for the oxidation of indane was proposed whose predictions were in satisfactory agreement with measured species profiles in both flames and jet-stirred reactor experiments. The main reaction pathways of consumption of indane have been derived from flow rate analyses in the two types of reactors. A comparison of the effect of the addition of three components of diesel fuel, namely indane, n-butylbenzene and n-propylcyclohexane (parts I and II of this series of paper), on the structure of a laminar lean premixed methane flame is also presented. (author)

  4. Metagenomics, metatranscriptomics and single cell genomics reveal functional response of active Oceanospirillales to Gulf oil spill

    SciTech Connect (OSTI)

    Mason, Olivia U.; Hazen, Terry C.; Borglin, Sharon; Chain, Patrick S. G.; Dubinsky, Eric A.; Fortney, Julian L.; Han, James; Holman, Hoi-Ying N.; Hultman, Jenni; Lamendella, Regina; Mackelprang, Rachel; Malfatti, Stephanie; Tom, Lauren M.; Tringe, Susannah G.; Woyke, Tanja; Zhou, Jizhong; Rubin, Edward M.; Jansson, Janet K.

    2012-06-12

    The Deepwater Horizon oil spill in the Gulf of Mexico resulted in a deep-sea hydrocarbon plume that caused a shift in the indigenous microbial community composition with unknown ecological consequences. Early in the spill history, a bloom of uncultured, thus uncharacterized, members of the Oceanospirillales was previously detected, but their role in oil disposition was unknown. Here our aim was to determine the functional role of the Oceanospirillales and other active members of the indigenous microbial community using deep sequencing of community DNA and RNA, as well as single-cell genomics. Shotgun metagenomic and metatranscriptomic sequencing revealed that genes for motility, chemotaxis and aliphatic hydrocarbon degradation were significantly enriched and expressed in the hydrocarbon plume samples compared with uncontaminated seawater collected from plume depth. In contrast, although genes coding for degradation of more recalcitrant compounds, such as benzene, toluene, ethylbenzene, total xylenes and polycyclic aromatic hydrocarbons, were identified in the metagenomes, they were expressed at low levels, or not at all based on analysis of the metatranscriptomes. Isolation and sequencing of two Oceanospirillales single cells revealed that both cells possessed genes coding for n-alkane and cycloalkane degradation. Specifically, the near-complete pathway for cyclohexane oxidation in the Oceanospirillales single cells was elucidated and supported by both metagenome and metatranscriptome data. The draft genome also included genes for chemotaxis, motility and nutrient acquisition strategies that were also identified in the metagenomes and metatranscriptomes. These data point towards a rapid response of members of the Oceanospirillales to aliphatic hydrocarbons in the deep sea.

  5. Is It Homogeneous or Heterogeneous Catalysis Derived from [RhCp*Cl2]2? In Operando-XAFS, Kinetic and Crucial Kinetic Poisoning Evidence for Subnanometer Rh4 Cluster-Based Benzene Hydrogenation Catalysis

    SciTech Connect (OSTI)

    Bayram, Ercan; Linehan, John C.; Fulton, John L.; Roberts, John A.; Szymczak, Nathaniel; Smurthwaite, Tricia D.; Ozkar, Saim; Balasubramanian, Mahalingam; Finke, Richard G.

    2011-11-23

    Determining the true, kinetically dominant catalytically active species, in the classic benzene hydrogenation system pioneered by Maitlis and co-workers 34 years ago starting with [RhCp*Cl2]2 (Cp* = [{eta}5-C5(CH3)5]), has proven to be one of the most challenging case studies in the quest to distinguish single-metal-based 'homogeneous' from polymetallic, 'heterogeneous' catalysis. The reason, this study will show, is the previous failure to use the proper combination of (i) operando spectroscopy to determine the dominant form(s) of the precatalyst's mass under catalysis (i.e., operating) conditions, plus then and crucially also (ii) the previous lack of the necessary kinetic studies, catalysis being a 'wholly kinetic phenomenon' as J. Halpern long ago noted. An important contribution from this study will be to reveal the power of quantitiative kinetic poisoning experiments for distinguishing single-metal, or in this case subnanometer Rh4 cluster-based catalysis from larger, polymetallic Rh(0)n nanoparticle catalysis, at least under favorable conditions. The combined operando-XAFS (X-ray absorption fine structure) spectroscopy and kinetic evidences provide a compelling case for Rh4-based, with average stoichiometry 'Rh4Cp*2.4Cl4Hc', benzene hydrogenation catalysis in 2-propanol with added Et3N and at 100 C and 50 atm initial H2 pressure. The results also reveal, however, that if even ca. 1.4% of the total soluble Rh(0)n had formed nanoparticles, then those Rh(0)n nanoparticles would have been able to account for all the observed benzene hydrogenation catalytic rate (using commercial, ca. 2 nm, polyethyleneglycol-dodecylether hydrosol stabilized Rh(0)n nanoparticles as a model system). The results 'especially the poisoning methodology developed and employed' are of significant, broader interest since determining the nature of the true catalyst continues to be a central, often vexing issue in any and all catalytic reactions. The results are also of fundamental interest in that they add to a growing body of evidence indicating that certain, appropriately ligated, coordinatively unsaturated, subnanometer M4 transition-metal clusters can be relatively robust catalysts. Also demonstrated herein is that Rh4 clusters are poisoned by Hg(0), demonstrating for the first time that the classic Hg(0) poisoning test of 'homogeneous' vs 'heterogeneous'catalysts cannot distinguish Rh4-based subnanometer catalysts from Rh(0)n nanoparticle catalysts, at least for the present examples of these two specific, Rh-based catalysts.

  6. Method of uranium reclamation from aqueous systems by reactive ion exchange. [US DOE patent application; anion exchange resin of copolymerized divinyl-benzene and styrene having quarternary ammonium groups and bicarbonate ligands

    DOE Patents [OSTI]

    Maya, L.

    1981-11-05

    A reactive ion exchange method for separation and recovery of values of uranium, neptunium, plutonium, or americium from substantially neutral aqueous systems of said metals comprises contacting said system with an effective amount of a basic anion exchange resin of copolymerized divinyl-benzene and styrene having quarternary ammonium groups and bicarbonate ligands to achieve nearly 100% sorption of said actinyl ion onto said resin and an aqueous system practically free of said actinyl ions. The method is operational over an extensive range of concentrations from about 10/sup -6/ M to 1.0 M actinyl ion and a pH range of about 4 to 7. The method has particulr application to treatment of waste streams from Purex-type nuclear fuel reprocessing facilities and hydrometallurgical processes involving U, Np, P, or Am.

  7. Rapid microwave hydrothermal synthesis of ZnGa{sub 2}O{sub 4} with high photocatalytic activity toward aromatic compounds in air and dyes in liquid water

    SciTech Connect (OSTI)

    Sun Meng; Li Danzhen; Zhang Wenjuan; Chen Zhixin; Huang Hanjie; Li Wenjuan; He Yunhui; Fu Xianzhi

    2012-06-15

    ZnGa{sub 2}O{sub 4} was synthesized from Ga(NO{sub 3}){sub 3} and ZnCl{sub 2} via a rapid and facile microwave-assisted hydrothermal method. The photocatalytic properties of the as-prepared ZnGa{sub 2}O{sub 4} were evaluated by the degradation of pollutants in air and aqueous solution under ultraviolet (UV) light illumination. The results demonstrated that ZnGa{sub 2}O{sub 4} had exhibited efficient photocatalytic activities higher than that of commercial P25 (Degussa Co.) in the degradation of benzene, toluene, and ethylbenzene, respectively. In the liquid phase degradation of dyes (methyl orange, Rhodamine B, and methylene blue), ZnGa{sub 2}O{sub 4} has also exhibited remarkable activities higher than that of P25. After 32 min of UV light irradiation, the decomposition ratio of methyl orange (10 ppm, 150 mL) over ZnGa{sub 2}O{sub 4} (0.06 g) was up to 99%. The TOC tests revealed that the mineralization ratio of MO (10 ppm, 150 mL) was 88.1% after 90 min of reaction. A possible mechanism of the photocatalysis over ZnGa{sub 2}O{sub 4} was also proposed. - Graphical abstract: In the degradation of RhB under UV light irradiation, ZnGa{sub 2}O{sub 4} had exhibited efficient photo-activity, and after only 24 min of irradiation the decomposition ratio was up to 99.8%. Highlights: Black-Right-Pointing-Pointer A rapid and facile M-H method to synthesize ZnGa{sub 2}O{sub 4} photocatalyst. Black-Right-Pointing-Pointer The photocatalyst exhibits high activity toward benzene and dyes. Black-Right-Pointing-Pointer The catalyst possesses more surface hydroxyl sites than TiO{sub 2} (P25). Black-Right-Pointing-Pointer Deep oxidation of different aromatic compounds and dyes over catalyst.

  8. Variations in the structure of aromatic solvents under the influence of microadditives of the C{sub 60} fullerene

    SciTech Connect (OSTI)

    Ginzburg, B. M. Tuichiev, Sh.

    2007-02-15

    The structural ordering of aromatic solvents is investigated using wide-angle X-ray diffraction. It is shown that the degree of structural ordering of aromatic solvents at room temperature decreases in the following sequence: benzene, toluene, and n-xylene. The introduction of the C{sub 60} fullerene ({approx}0.001%) into these solvents leads to an increase in the degree of their ordering. Upon introduction of the fullerene, the degree of structural ordering increases significantly in n-xylene and only slightly in toluene and remains virtually unchanged in benzene. An analysis of the small-angle X-ray diffraction patterns of C{sub 60} fullerene solutions in benzene likewise demonstrates that the introduction of the fullerene into benzene leads to an insignificant change in the degree of structural ordering of this solvent. The specific features of the structure and behavior of benzene upon interaction with C{sub 60} fullerene additives are discussed.

  9. Infrared identification of the {sigma}-complex of Cl-C{sub 6}H{sub 6} in the reaction of chlorine atom and benzene in solid para-hydrogen

    SciTech Connect (OSTI)

    Bahou, Mohammed; Witek, Henryk; Lee, Yuan-Pern

    2013-02-21

    The reaction of a chlorine atom with benzene (C{sub 6}H{sub 6}) is important in organic chemistry, especially in site-selective chlorination reactions, but its product has been a subject of debate for five decades. Previous experimental and theoretical studies provide no concrete conclusion on whether the product is a {pi}- or {sigma}-form of the Cl-C{sub 6}H{sub 6} complex. We took advantage of the diminished cage effect of para-hydrogen (p-H{sub 2}) to produce Cl in situ to react with C{sub 6}H{sub 6} (or C{sub 6}D{sub 6}) upon photolysis of a Cl{sub 2}/C{sub 6}H{sub 6} (or C{sub 6}D{sub 6})/p-H{sub 2} matrix at 3.2 K. The infrared spectrum, showing intense lines at 1430.5, 833.6, 719.8, 617.0, and 577.4 cm{sup -1}, and several weaker ones for Cl-C{sub 6}H{sub 6}, and the deuterium shifts of observed new lines unambiguously indicate that the product is a 6-chlorocyclohexadienyl radical, i.e., the {sigma}-complex of Cl-C{sub 6}H{sub 6}. Observation of the {sigma}-complex rather than the {pi}-complex indicates that the {sigma}-complex is more stable in solid p-H{sub 2} at 3.2 K. The spectral information is crucial for further investigations of the Cl + C{sub 6}H{sub 6} reaction either in the gaseous or solution phase.

  10. Density functional theory study of the interaction of vinyl radical, ethyne, and ethene with benzene, aimed to define an affordable computational level to investigate stability trends in large van der Waals complexes

    SciTech Connect (OSTI)

    Maranzana, Andrea E-mail: anna.giordana@hotmail.com E-mail: mauro.causa@unina.it Giordana, Anna E-mail: anna.giordana@hotmail.com E-mail: mauro.causa@unina.it Indarto, Antonius Tonachini, Glauco; Barone, Vincenzo E-mail: anna.giordana@hotmail.com E-mail: mauro.causa@unina.it; Causà, Mauro E-mail: anna.giordana@hotmail.com E-mail: mauro.causa@unina.it; Pavone, Michele E-mail: anna.giordana@hotmail.com E-mail: mauro.causa@unina.it

    2013-12-28

    Our purpose is to identify a computational level sufficiently dependable and affordable to assess trends in the interaction of a variety of radical or closed shell unsaturated hydro-carbons A adsorbed on soot platelet models B. These systems, of environmental interest, would unavoidably have rather large sizes, thus prompting to explore in this paper the performances of relatively low-level computational methods and compare them with higher-level reference results. To this end, the interaction of three complexes between non-polar species, vinyl radical, ethyne, or ethene (A) with benzene (B) is studied, since these species, involved themselves in growth processes of polycyclic aromatic hydrocarbons (PAHs) and soot particles, are small enough to allow high-level reference calculations of the interaction energy ΔE{sub AB}. Counterpoise-corrected interaction energies ΔE{sub AB} are used at all stages. (1) Density Functional Theory (DFT) unconstrained optimizations of the A−B complexes are carried out, using the B3LYP-D, ωB97X-D, and M06-2X functionals, with six basis sets: 6-31G(d), 6-311 (2d,p), and 6-311++G(3df,3pd); aug-cc-pVDZ and aug-cc-pVTZ; N07T. (2) Then, unconstrained optimizations by Møller-Plesset second order Perturbation Theory (MP2), with each basis set, allow subsequent single point Coupled Cluster Singles Doubles and perturbative estimate of the Triples energy computations with the same basis sets [CCSD(T)//MP2]. (3) Based on an additivity assumption of (i) the estimated MP2 energy at the complete basis set limit [E{sub MP2/CBS}] and (ii) the higher-order correlation energy effects in passing from MP2 to CCSD(T) at the aug-cc-pVTZ basis set, ΔE{sub CC-MP}, a CCSD(T)/CBS estimate is obtained and taken as a computational energy reference. At DFT, variations in ΔE{sub AB} with basis set are not large for the title molecules, and the three functionals perform rather satisfactorily even with rather small basis sets [6-31G(d) and N07T], exhibiting deviation from the computational reference of less than 1 kcal mol{sup −1}. The zero-point vibrational energy corrected estimates Δ(E{sub AB}+ZPE), obtained with the three functionals and the 6-31G(d) and N07T basis sets, are compared with experimental D{sub 0} measures, when available. In particular, this comparison is finally extended to the naphthalene and coronene dimers and to three π−π associations of different PAHs (R, made by 10, 16, or 24 C atoms) and P (80 C atoms)

  11. Evaluation of a Polyvinyl Toluene Neutron Counter Array (Conference...

    Office of Scientific and Technical Information (OSTI)

    Results demonstrate that analysis with Monte Carlo N-Particle (MCNP) can be used to obtain a better understanding of field measurement results and aid in algorithm development for ...

  12. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect (OSTI)

    Ramanathan Sampath

    2004-09-30

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period April 01, 2004 to September 30, 2004 which covers the fourth six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. During this reporting period, work was under way and the electrical conductivity experimental system was set up at the Atlanta University Center. Following the set-up of the emulsion measurement system, the electronic instruments and data acquisition modules involved were tested for proper operation of the system. Then, the conductivity output was normalized with that obtained for 10mM NaCl water. Radial coreflooding experiments with ethanol injection prior to and after water injection were completed to assess the effectiveness of the surfactant flooding in the recovery of condensate by our industrial partner, Surtek, CO, in this reporting period. In Run 1, 10 mM NaCl without ethanol injection recovered 31.5% of the initial ethyl benzene saturation. Injection of ethanol following 10 mM NaCl produced a tertiary ethyl benzene bank with maximum ethyl benzene cuts of 32%. In Run 2, 50 vol% of pure (100%) ethanol was injected and flowed through the Berea sandstone after Ethyl Benzene Saturation. 69% of the initial ethyl benzene was recovered. Results of the radial corefloods are very encouraging. Emulsion conductivity measurements for conjugate pair phases are in progress at Morehouse.

  13. Direct Push Groundwater Circulation Wells for Remediation of BTEX and Volatile Organics

    SciTech Connect (OSTI)

    Borden, R. E.; Cherry, Robert Stephen

    2000-09-01

    Direct push groundwater circulation wells (DP-GCW) are a promising technology for remediation of groundwater contaminated with dissolved hydrocarbons and chlorinated solvents. In these wells, groundwater is withdrawn from the formation at the bottom of the well, aerated and vapor stripped and injected back into the formation at or above the water table. Previous field studies have shown that: (a) GCWs can circulate significant volumes of groundwater; and (b) GCWs can effectively remove volatile compounds and add oxygen. In this work, we describe the development and field-testing of a system of DP-GCWs for remediation of volatile organics such as benzene, toluene, ethylbenzene, and toluene (BTEX). The GCWs were constructed with No. 20 slotted well screen (2.4 cm ID) and natural sand pack extending from 1.5 to 8.2 m below grade. Air is introduced ~7.5 m below grade via 0.6 cm tubing. Approximately 15% of the vertical length of the air supply tubing is wrapped in tangled mesh polypropylene geonet drainage fabric to provide surface area for biological growth and precipitation of oxidized iron. These materials were selected to allow rapid installation of the GCWs using 3.8 cm direct push Geoprobe® rods, greatly reducing well installation costs. Laboratory testing of these sparged wells and computational fluid dynamics (CFD) modeling showed that these wells, although they used only about 1 L/min of air, could circulate about 1 L/min of water through the surrounding aquifer. This flow was sufficient to capture all of a flowing contaminant if the wells are sufficiently closely together, about 1 meter on center depending on the air flow rate supplied, in a line across the plume. The CFD work showed the details of this ability to capture, and also showed that unforeseen heterogeneities in the aquifer such as a gradient of permeability or a thin impermeable layer (such as a clay layer) did not prevent the system from working largely as intended. The system was tested in a petroleum contaminated aquifer near Rocky Point, NC. The contaminant plume there is approximately 10 m deep, 50 m wide and contains up to 4 µg/L total BTEX and 75 µg/L dissolved iron. An extensive pilot test was first performed to estimate the zone of influence for a single well. At this site an air injection rate of 1.2 L/min resulted in a water flow rate of 1 to 2 L/min based on bromide dilution tests in the GCW. The GCW increased the dissolved oxygen concentration in the discharge water to between 6 and 8 µg/L and reduced contaminant concentrations to less than 20 µg/L total BTEX. Monitoring results from a 73 day pilot test were then used to define the zone of influence for a single DP-GCW and to design a full scale barrier system.

  14. Direct Push Groundwater Circulation Wells for Remediation of BTEX and Volatile Organics

    SciTech Connect (OSTI)

    Borden, R.C.; Cherry, R.S.

    2000-09-30

    Direct push groundwater circulation wells (DP-GCW) are a promising technology for remediation of groundwater contaminated with dissolved hydrocarbons and chlorinated solvents. In these wells, groundwater is withdrawn from the formation at the bottom of the well, aerated and vapor stripped and injected back into the formation at or above the water table. Previous field studies have shown that: (a) GCWs can circulate significant volumes of groundwater; and (b) GCWs can effectively remove volatile compounds and add oxygen. In this work, we describe the development and field-testing of a system of DP-GCWs for remediation of volatile organics such as benzene, toluene, ethylbenzene, and toluene (BTEX). The GCWs were constructed with No. 20 slotted well screen (2.4 cm ID) and natural sand pack extending from 1.5 to 8.2 m below grade. Air is introduced {approximately}7.5 m below grade via 0.6 cm tubing. Approximately 15% of the vertical length of the air supply tubing is wrapped in tangled mesh polypropylene geonet drainage fabric to provide surface area for biological growth and precipitation of oxidized iron. These materials were selected to allow rapid installation of the GCWs using 3.8 cm direct push Geoprobe{reg_sign} rods, greatly reducing well installation costs. Laboratory testing of these sparged wells and computational fluid dynamics (CFD) modeling showed that these wells, although they used only about 1 L/min of air, could circulate about 1 L/min of water through the surrounding aquifer. This flow was sufficient to capture all of a flowing contaminant if the wells are sufficiently closely together, about 1 meter on center depending on the air flow rate supplied, in a line across the plume. The CFD work showed the details of this ability to capture, and also showed that unforeseen heterogeneities in the aquifer such as a gradient of permeability or a thin impermeable layer (such as a clay layer) did not prevent the system from working largely as intended. The system was tested in a petroleum contaminated aquifer near Rocky Point, NC. The contaminant plume there is approximately 10 m deep, 50 m wide and contains up to 4 {micro}g/L total BTEX and 75 {micro}g/L dissolved iron. An extensive pilot test was first performed to estimate the zone of influence for a single well. At this site an air injection rate of 1.2 L/min resulted in a water flow rate of 1 to 2 L/min based on bromide dilution tests in the GCW. The GCW increased the dissolved oxygen concentration in the discharge water to between 6 and 8 {micro}g/L and reduced contaminant concentrations to less than 20 {micro}g/L total BTEX. Monitoring results from a 73 day pilot test were then used to define the zone of influence for a single DP-GCW and to design a full scale barrier system.

  15. A novel plug-flow digester for biogasification of conventional and hazardous organics

    SciTech Connect (OSTI)

    Ghosh, S.; Kato, Y.; Liu, T.; Fukushi, K.

    1996-12-31

    A novel plug-flow digestion system of simple construction was designed, fabricated and operated for several years with a synthetic mixture of solid and liquid wastes simulating conditions south of the US-Mexican border and other developing countries. Benzene, toluene, and o-xylene (BTX) were mixed with the synthetic feed in several phases of this research to simulate field conditions where these solvents are discharged to public sewers and mixed with non-hazardous pollutants. The mesophilic plug-flow digester exhibited a high gas yield of 0.46 SCM /kg VS added, a methane content of 77 mol%, and a VS reduction of 75% at an HRT of 13 days with a 96% biodegradation of the feed toluene. At a feed concentration of 50 mg/l, toluene did not inhibit anaerobic fermentation. Gas and methane yields, and VS and COD conversion efficiencies were about the same with or without toluene present in the feed. At a reduced HRT of 8 days, a high feed COD concentration of 50,000 mg/l, and a loading rate of 0.48 kg VS/m{sup 3}-day, the digester afforded a gas yield of 3.1 SCM /kg VS added, and a methane content of 67 mol%. Benzene, toluene, and o-xylene were biodegraded at efficiencies of 94%, 90%, and 88%, respectively. The degradation kinetics of the xenobiotic compound could be described by a model based on cometabolic degradation of these secondary substrates.

  16. PREPARATION OF HIGH PURITY UF$sub 4$

    DOE Patents [OSTI]

    Magner, J.E.; Long, R.S.; Ellis, D.A.; Grinstead, R.R.

    1962-04-17

    S>A process for preparing very highly pure uranous tetrafluoride from impure uranium laden solvent extraction strip solutions, ion exchange process and resin-inpulp process eluate solutions which are at least 8M in hydrochloric acid is described. The process first comprises treating any of the above-mentioned solutions with a reducing agent to reduce the uranium to the + 4 oxidation state, and then contacting the reduced solution with an extractant phase comprising about 10 to 70% of tri-butyl phosphate in an organic solvent-diluent selected from benzene, ethyl-benzene, chlorobenzene, xylene, kerosene, or the like. The uranium is extracted into the extractant phase and is subsequently precipitated by treating the extractant with an aqueous fluoride solution. The highly pure uranous tetrafluoride precipitate is separated from the phases and recovered for subsequent utilization. (AEC)

  17. Chemistry of Furan Conversion into Aromatics and Olefins over HZSM-5: A Model Biomass Conversion Reaction

    SciTech Connect (OSTI)

    Cheng, Yu-Ting; Huber, George W.

    2011-06-03

    The conversion of furan (a model of cellulosic biomass) over HZSM-5 was investigated in a thermogravimetric analysis–mass spectrometry system, in situ Fourier transform infrared analysis, and in a continuous-flow fixed-bed reactor. Furan adsorbed as oligomers at room temperature with a 1.73 of adsorbed furan/Al ratio. These oligomers were polycyclic aromatic compounds that were converted to CO, CO?, aromatics, and olefins at temperatures from 400 to 600 °C. Aromatics (e.g., benzene, toluene, and naphthalene), oligomer isomers (e.g., benzofuran, 2,2-methylenebisfuran, and benzodioxane), and heavy oxygenates (C??{sub +} oligomers) were identified as intermediates formed inside HZSM-5 at different reaction temperatures. During furan conversion, graphite-type coke formed on the catalyst surface, which caused the aromatics and olefins formation to deactivate within the first 30 min of time on-stream. We have measured the effects of space velocity and temperature for furan conversion to help us understand the chemistry of biomass conversion inside zeolite catalysts. The major products for furan conversion included CO, CO?, allene, C?–C? olefins, benzene, toluene, styrene, benzofuran, indene, and naphthalene. The aromatics (benzene and toluene) and olefins (ethylene and propylene) selectivity decreased with increasing space velocity. Unsaturated hydrocarbons such as allene, cyclopentadiene, and aromatics selectivity increased with increasing space velocity. The product distribution was selective to olefins and CO at high temperatures (650 °C) but was selective to aromatics (benzene and toluene) at intermediate temperatures (450–600 °C). At low temperatures (450 °C), benzofuran and coke contributed 60% of the carbon selectivity. Several different reactions were occurring for furan conversion over zeolites. Some important reactions that we have identified in this study include Diels–Alder condensation (e.g., two furans form benzofuran and water), decarbonylation (e.g., furan forms CO and allene), oligomerization (allene forms olefins and aromatics plus hydrogen), and alkylation (e.g., furan plus olefins). The product distribution was far from thermodynamic equilibrium.

  18. Electron localization in a mixed-valence diniobium benzene complex...

    Office of Scientific and Technical Information (OSTI)

    Investigation of the solidstate and solution phase structure using single-crystal X-ray diffraction, cyclic voltammetry, magnetic susceptibility, and multinuclear NMR spectroscopy ...

  19. Carbon Nanothreads from Compressed Benzene | U.S. DOE Office...

    Office of Science (SC) Website

    variations, such as cross-linking or chemical functionalization (adding atoms or small ... properties associated with their low dimensionality and graphite-like chemical bonding. ...

  20. The use of white-rot fungi as active biofilters

    SciTech Connect (OSTI)

    Braun-Luellemann, A.; Johannes, C.; Majcherczyk, A.; Huettermann, A.

    1995-12-31

    White-rot fungi, growing on lignocellulosic substrates, have been successfully used as active organisms in biofilters. Filters using these fungi have a very high biological active surface area, allowing for high degrees of retention, a comparatively low pressure drop, and a high physical stability. The unspecific action of the extracellular enzymes of the white-rot fungi allows for the degradation of a wide variety of substances by the same organism. Degradation of several compounds in the gas phase by the white-rot fungi Trametes versicolor, Pleurotus ostreatus, Bjerkandera adusta, and Phanerochaete chrysosporium was tested. Among the aromatic solvents, styrene was the compound that was most readily degraded, followed by ethylbenzene, xylenes, and toluene. Tetrahydrofuran and dichloromethane were also degraded, whereas dioxane could not be attacked by fungi under the conditions used. Acrylonitrile and aniline were degraded very well, whereas pyridine was resistant to degradation. The process for removing styrene is now in the scaling-up stage.

  1. INVESTIGATION OF PHASE AND EMULSION BEHAVIOR, SURFACTANT RETENTION, AND CONDENSATE RECOVERY FOR CONDENSATE/WATER/ETHANOL MIXTURES

    SciTech Connect (OSTI)

    Ramanathan Sampath

    2005-12-01

    This final technical report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period October 01, 2002 to September 30, 2005, which covers the total performance period of the project. During this period, work was conducted to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number was used as the model condensate. Salinity scans were performed for 0, 5, 10, 20, 50, 100, 250, 500, and 1000 mM salt concentrations at room temperature to identify the optimal salinity and salinity intervals in which all phases coexisted. It was found that only two phases formed, and salinity has no significant effect in the volumes of the phases formed. Experiments were repeated at 30 C and observed salinity has no effect at higher temperatures as well. Following the salinity experiments, measurements were made with 10mM NaCl water for surfactant concentrations from 2 to 70 volume percent at room temperature. It was found that only two phases were formed upto 60 vol% concentration of the surfactant. Above 60 vol% surfactant, the mixture produced only a single phase. Experiments were repeated from 2 to 70 C and observed that temperature has no significant effect on the number of phases formed. At the temperatures and surfactant concentration tested, volume fraction of the aqueous bottom phase was found to be larger than that of the top phase. Electrical conductivity measurements were then conducted for bottom/top, and top/bottom conjugate pair phases of the ethylbenzene/water/ethanol system formed by mixing ethanol at various volume percentages including 2,10,33,and 56% while keeping the volumes of ethylbenzene and water the same in the mixture. Electrical conductivity of the bottom phase decreased as ethanol volume fraction in the mixture increased. Conductivity of the top phase was found small and remained almost the same for variations in ethanol volume fraction in the mixture. Also inversion phenomena was observed. Prediction of the conductivity data obtained was then conducted employing a theoretical model developed in this project based on Maxwell relations. Results of the comparisons for 2, 10, 33, and 56% ethanol volume in the mixture are presented here. A good agreement was obtained between the predicted emulsion conductivities and the measured values. Work was also conducted at Surtek, Golden, CO, our industrial partner in this project, to measure the effectiveness for condensate recovery employing coreflooding techniques. In Run 1 of the radial coreflooding experiments conducted, 10 mM NaCl without ethanol injection recovered 31.5% of the initial ethyl benzene saturation. Injection of ethanol following 10 mM NaCl produced a tertiary ethyl benzene bank with maximum ethyl benzene cuts of 32%. In Run 2, 50 vol% of pure (100%) ethanol was injected and flowed through the Berea sandstone after Ethyl Benzene Saturation. 69% of the initial ethyl benzene was recovered. While 50 vol% of ethanol injection does not make economic sense when injecting a large fraction of a pore volume, injection of sufficient volume to remove water and condensate from around the near well bore area of a gas well could be economic.

  2. Superfund Record of Decision (EPA region 5): Seymour Recycling Corporation, Seymour, Indiana, September 1986. Final report

    SciTech Connect (OSTI)

    Not Available

    1986-09-30

    The Seymour Recycling Corporation (SRC) operated a processing center for waste chemicals. Toxic and hazardous wastes, including solvents, metal finishing wastes, and other materials, accumulated on the site in 55-gallon drums, bulk tanks, and other containers. Wastes leaked and spilled from the drums creating fire and odor problems. A Consent Decree resulted in the removal of the upper one foot of contaminated soil from about 75% of the site's surface. Contaminated soil remains, however, and extends throughout the shallow and deep aquifer. The primary contaminants of concern include: VOCs, organics, TCE, DCE, benzene, toluene, and heavy metals. Selected remedies have been proposed and are included.

  3. Secondary battery containing zinc electrode with modified separator and method

    DOE Patents [OSTI]

    Poa, D.S.

    1984-02-16

    A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

  4. Secondary battery containing zinc electrode with modified separator and method

    DOE Patents [OSTI]

    Poa, David S.; Yao, Neng-Ping

    1985-01-01

    A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

  5. Make aromatics from LPG

    SciTech Connect (OSTI)

    Doolan, P.C. ); Pujado, P.R. )

    1989-09-01

    Liquefied petroleum gas (LPG) consists mainly of the propane and butane fraction recovered from gas fields, associated petroleum gas and refinery operations. Apart from its use in steam cracking and stream reforming, LPG has few petrochemical applications. The relative abundance of LPG and the strong demand for aromatics - benzene, toluene and xylenes (BTX) - make it economically attractive to produce aromatics via the aromatization of propane and butanes. This paper describes the Cyclar process, which is based on a catalyst formulation developed by BP and which uses UOP's CCR catalyst regeneration technology, converts propane, butanes or mixtures thereof to petrochemical-quality aromatics in a single step.

  6. Storm-water characterization and lagoon sediment analysis, Grand Forks Air Force Base, North Dakota. Final report

    SciTech Connect (OSTI)

    Garland, J.G.; Vaughn, R.W.; Scott, P.T.

    1990-08-01

    Sampling was conducted in the wastewater treatment lagoons and stormwater runoff at Grand Forks AFB. The base was concerned about whether the unlined lagoons were creating a potential groundwater contamination problem and whether their stormwater runoff met North Dakota state stream standards. Lagoon sediment did not contain Extraction Procedure hazardous chemicals. Stormwater runoff exceeded state standards for boron, phosphates, and phenols and contained trace levels of methylene chloride. Characterization of lagoon influent showed it to be generally representative of domestic sewage, but also contained trace levels of boron, phenols, toluene, cyanide, chloroform, methylene chloride and ethyl benzene.

  7. Investigation of optical limiting properties of Aluminium nanoparticles prepared by pulsed laser ablation in different carrier media

    SciTech Connect (OSTI)

    Kuladeep, Rajamudili; Jyothi, L.; Narayana Rao, D.; Prakash, P.; Mayank Shekhar, S.; Durga Prasad, M.

    2013-12-28

    In this communication, we carried out the systematic investigation of nonlinear absorption and scattering properties of Aluminium nanoparticles (Al NPs) in various polar and non-polar solvents. Al NPs were synthesized with pulsed Nd:YAG laser operated at 1064 nm by ablating Al target in polar and non-polar liquid environment like chloroform, chlorobenzene, toluene, benzene, and carbon tetrachloride. Synthesized Al NPs colloids of various solvents differ in appearance and UV-Vis extinction spectra exhibit absorption in the UV region. The characterization of Al NPs performed by Transmission electron microscopy (TEM) studies reveal that NPs are made up of a well crystallized Al inner part (bright zone) embedded with an amorphous metal Al shell (dark region). Growth, aggregation, and precipitation mechanisms which influence the optical properties and stability of NPs are found to be related to the dipole moment of the surrounding liquid environment. The nonlinear absorption and scattering studies are performed by open aperture Z-scan technique with 532 nm under nanosecond pulse excitation. The Z-scan measurements are fitted theoretically to estimate both two-photon absorption (TPA) and nonlinear scattering (NLS) coefficients. In polar solvents like chlorobenzene, chloroform synthesized Al NPs exhibited higher TPA, NLS coefficient values, and lower optical limiting threshold values in comparison with partially polar solvent like toluene and non-polar solvents like benzene and carbontetrachloride. These results indicate the potential use of Al NPs as a versatile optical limiting material.

  8. Carbon-Supported bimetallic Pd-Fe catalysts for vapor-phase hydrodeoxygenation of guaiacol

    SciTech Connect (OSTI)

    Sun, Junming; Karim, Ayman M.; Zhang, He; Kovarik, Libor; Li, Xiaohong S.; Hensley, Alyssa; McEwen, Jean-Sabin; Wang, Yong

    2013-10-01

    Abstract Carbon supported metal catalysts (Cu/C, Fe/C, Pd/C, Pt/C, PdFe/C and Ru/C) have been prepared, characterized and tested for vapor-phase hydrodeoxygenation (HDO) of guaiacol (GUA) at atmospheric pressure. Phenol was the major intermediate on all catalysts. Over the noble metal catalysts saturation of the aromatic ring was the major pathway observed at low temperature (250 °C), forming predominantly cyclohexanone and cyclohexanol. Substantial ring opening reaction was observed on Pt/C and Ru/C at higher reaction temperatures (e.g., 350 °C). Base metal catalysts, especially Fe/C, were found to exhibit high HDO activity without ring-saturation or ring-opening with the main products being benzene, phenol along with small amounts of cresol, toluene and trimethylbenzene (TMB). A substantial enhancement in HDO activity was observed on the PdFe/C catalysts. Compared with Fe/C, the yield to oxygen-free aromatic products (i.e., benzene/toluene/TMB) on PdFe/C increased by a factor of four at 350 °C, and by approximately a factor of two (83.2% versus 43.3%) at 450 °C. The enhanced activity of PdFe/C is attributed to the formation of PdFe alloy as evidenced by STEM, EDS and TPR.

  9. Benzene TCLP results from saltstone prepared with 2X ITP flowsheet concentrations of phenylborates

    SciTech Connect (OSTI)

    Poirier, M.R.

    2000-07-25

    The Savannah River Site (SRS) teamed with the Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), and ITT Flygt Corporation to conduct a test program evaluating shrouded axial propeller mixers (Flygt mixers) for heel removal in SRS Tank 19. SRS is identifying and investigating techniques to remove sludge heels from waste tanks such as Tank 19.

  10. Non-Incineration Treatment to Reduce Benzene and VOC Emissions from Green Sand Molding Systems

    SciTech Connect (OSTI)

    Fred S. Cannon; Robert C. Voigt

    2002-06-28

    Final report describing laboratory, pilot scale and production scale evaluation of advanced oxidation systems for emissions and cost reduction in metal casting green sand systems.

  11. Effect of hydrotropic salts on phase relationships involving hydrocarbons, water, and alcohols

    SciTech Connect (OSTI)

    Ho, P.C.; Kraus, K.A.

    1980-01-01

    Hydrotropic salts, which can increase the solubility of organic materials in aqueous solutions, are useful to tertiary oil recovery. We have examined effects on solubility of hydrocarbons in water (with and without alcohols) through addition of inorganic hydrotropic salts, such as perchlorates, thiocyanates, and iodides - high in the usual Hofmeister series - and of organic salts such as short chain alkyl benzene sulfonates and other salts based on substituted benzene derivatives. Although the inorganic salts are relatively ineffective in increasing solubility of hydrocarbons in water, many of the organic salts are excellent hydrotropic agents for hydrocarbons. We have examined the phase relationships for several series of aromatic salts such as sulfonates, carboxylates and hydroxycarboxylates, as a function of alkyl-carbon substitution in three-component (hydrocarbon, salt, water) and in four-component (hydrocarbon, salt, alcohol, water) systems. We have also examined miscibility relationships for a given hydrotropic salt as the chain length of alkanes and alkyl benzenes is systematically varied. While miscibilities decrease with increase in chain length of the hydrocarbon, the hydrotropic properties in these systems increase rapidly with the number of alkyl carbons on the benzene ring of the salts and they are relatively insensitive to the type of charged group (sulfonate vs carboxylate) attached to the benzene ring. However, there were significant increases in hydrotropy as one goes from equally substituted sulfonates or carboxylates to salicylates. A number of salts have been identified which have much greater hydrotropic properties for hydrocarbons than such well-known hydrotropic materials as toluene and xylene sulfonates.

  12. Mass transfer of volatile organic compounds from drinking water to indoor air: The role of residential dishwashers

    SciTech Connect (OSTI)

    Howard-Reed, C.; Corsi, R.L.; Moya, J.

    1999-07-01

    Contaminated tap water may be a source of volatile organic compounds (VOCs) in residential indoor air. To better understand the extent and impact of chemical emissions from this source, a two-phase mass balance model was developed based on mass transfer kinetics between each phase. Twenty-nine experiments were completed using a residential dishwasher to determine model parameters. During each experiment, inflow water was spiked with a cocktail of chemical tracers with a wide range of physicochemical properties. In each case, the effects of water temperature, detergent, and dish-loading pattern on chemical stripping efficiencies and mass transfer coefficients were determined. Dishwasher headspace ventilation rates were also measured using an isobutylene tracer gas. Chemical stripping efficiencies for a single cycle ranged from 18% to 55% for acetone, from 96% to 98% for toluene, and from 97% to 98% for ethylbenzene and were consistently 100% for cyclohexane. Experimental results indicate that dishwashers have a relatively low but continuous ventilation rate that results in significant chemical storage within the headspace of the dishwasher. In conjunction with relatively high mass transfer coefficients, low ventilation rates generally lead to emissions that are limited by equilibrium conditions after approximately 1--2 min of dishwasher operation.

  13. Methods for chemical recovery of non-carrier-added radioactive tin from irradiated intermetallic Ti-Sb targets

    DOE Patents [OSTI]

    Lapshina, Elena V.; Zhuikov, Boris L.; Srivastava, Suresh C.; Ermolaev, Stanislav V.; Togaeva, Natalia R.

    2012-01-17

    The invention provides a method of chemical recovery of no-carrier-added radioactive tin (NCA radiotin) from intermetallide TiSb irradiated with accelerated charged particles. An irradiated sample of TiSb can be dissolved in acidic solutions. Antimony can be removed from the solution by extraction with dibutyl ether. Titanium in the form of peroxide can be separated from tin using chromatography on strong anion-exchange resin. In another embodiment NCA radiotin can be separated from iodide solution containing titanium by extraction with benzene, toluene or chloroform. NCA radiotin can be finally purified from the remaining antimony and other impurities using chromatography on silica gel. NCA tin-117m can be obtained from this process. NCA tin-117m can be used for labeling organic compounds and biological objects to be applied in medicine for imaging and therapy of various diseases.

  14. Selective aromatization of C[sub 3] and C[sub 4] paraffins over modified encilite catalysts. 1. Qualitative study

    SciTech Connect (OSTI)

    Jana, A.K.; Rao, M.S. . Department of Chemical Engineering)

    1993-06-01

    The catalytic activity of Zn-encilite in the aromatization of propane and n-butane has been studied by a comparative study of the yields of benzene, toluene, and xylenes (BTX) using propane and n-butane as feeds. The results showed that n-butane had better activity and selectivity to BTX than propane. The effects of reaction temperature, contact time, inlet concentration, poisoning with ammonia on H-encilite, and different degrees of ion exchange with Zn[sup 2+] ion were studied in detail in order to obtain information on the reaction mechanism. The results indicated that the activity and the selectivity were dictated by the acidity and Zn loading on the catalyst.

  15. Superfund Record of Decision (EPA Region 2): Hooker-102nd Street Landfill, Niagara Falls, NY. (First remedial action), September 1990. Final report

    SciTech Connect (OSTI)

    Not Available

    1990-09-26

    The 22-acre Hooker-102nd Street site is a former industrial landfill in the city of Niagara Falls, Niagara County, New York. The site is adjacent to, and partially within the Niagara River's 100-year floodplain. These studies and the Remedial Investigation (RI) initiated in 1984, identified contamination in ground water, onsite and offsite soil, rivershore sediment, and within a storm sewer. Additionally, the presence of a leachate plume of non-aqueous phase liquids (NAPLs) was discovered emanating from the landfill area. The Record of Decision (ROD) is the final remedy which addresses all of the contaminated media. The primary contaminants of concern affecting the soil, sediment, and ground water are VOCs including benzene, TCE, and toluene; other organics including PCBs and phenols; and metals including arsenic.

  16. Catalytic Fast Pyrolysis for the Production of the Hydrocarbon Biofuels

    SciTech Connect (OSTI)

    Nimlos, M. R.; Robichaud, D. J.; Mukaratate, C.; Donohoe, B. S.; Iisa, K.

    2013-01-01

    Catalytic fast pyrolysis is a promising technique for conversion of biomass into hydrocarbons for use as transportation fuels. For over 30 years this process has been studied and it has been demonstrated that oils can be produced with high concentrations of hydrocarbons and low levels of oxygen. However, the yields from this type of conversion are typically low and the catalysts, which are often zeolites, are quickly deactivated through coking. In addition, the hydrocarbons produced are primarily aromatic molecules (benzene, toluene, xylene) that not desirable for petroleum refineries and are not well suited for diesel or jet engines. The goals of our research are to develop new multifunction catalysts for the production of gasoline, diesel and jet fuel range molecules and to improve process conditions for higher yields and low coking rates. We are investigating filtration and the use of hydrogen donor molecules to improve catalyst performance.

  17. Product analysis from direct liquefaction of several high-moisture biomass feedstocks

    SciTech Connect (OSTI)

    Elliott, D.C.; Sealock, L.J. Jr.; Butner, R.S.

    1987-04-01

    Product analysis in support of the process development research in biomass direct liquefaction began at rudimentary level of determining solvent-soluble portions of the product. Analysis was soon extended to elemental analyses and proximate analyses, such as ash and moisture. Later, spectrometric analyses were performed followed by detailed chemical analyses used in conjunction with chromatographic separation techniques. At all stages of development, the significant differences in composition between the products of flash pyrolysis and high-pressure processing have been evident. While polar solvents are most effective for both products, less polar solvents such as methylene chloride and even benzene and toluene have been used as extractants for high-pressure product oils.

  18. Genome analysis and physiological comparison of Alicycliphilus denitrificans strains BC and K601T

    SciTech Connect (OSTI)

    Oosterkamp, Margreet J.; Veuskens, Teun; Saia, Flavia Talarico; Weelink, Sander A.B.; Goodwin, Lynne A.; Daligault, Hajnalka E.; Bruce, David; Detter, J. Chris; Tapia, Roxanne; Han, Cliff; Land, Miriam L; Hauser, Loren John; Langenhoff, A. M.; Gerritse, Jan; Van Berkel, Willem J. H.; Pieper, Dietmar; Junca, Howard; Smidt, Hauke; Schraa, Gosse; Davids, Mark; Schaap, Peter J; Plugge, Caroline M.; Stams, Alfons J. M.

    2013-01-01

    The genomes of the Betaproteobacteria Alicycliphilus denitrificans strains BC and K601T have been sequenced to get insight into the physiology of the two strains. Strain BC degrades benzene with chlorate as electron acceptor. The cyclohexanol-degrading denitrifying strain K601T is not able to use chlorate as electron acceptor, while strain BC cannot degrade cyclohexanol. The 16S rRNA sequences of strains BC and K601T are identical and the fatty acid methyl ester patterns of the strains are similar. Basic Local Alignment Search Tool (BLAST) analysis of predicted open reading frames of both strains showed most hits with Acidovorax sp. JS42, a bacterium that degrades nitro-aromatics. The genomes include strain-specific plasmids (pAlide201 in strain K601T and pAlide01 and pAlide02 in strain BC). Key genes of chlorate reduction in strain BC were located on a 120 kb megaplasmid (pAlide01), which was absent in strain K601T. Genes involved in cyclohexanol degradation were only found in strain K601T. Benzene and toluene are degraded via oxygenase-mediated pathways in both strains. Genes involved in the meta-cleavage pathway of catechol are present in the genomes of both strains. Strain BC also contains all genes of the ortho-cleavage pathway. The large number of mono- and dioxygenase genes in the genomes suggests that the two strains have a broader substrate range than known thus far.

  19. Fossil fuel and hydrocarbon conversion using hydrogen-rich plasmas. Topical report February 1994--February 1995

    SciTech Connect (OSTI)

    1995-02-01

    Experiments were made on use of H and CH plasmas for converting waste materials and heavy oils to H-rich transportation fuels. Batch and continuous experiments were conducted with an industrial microwave generator and a commercial microwave oven. A continuously circulating reactor was constructed for conducting experiments on flowing oils. Experiments on decomposition of scrap tires showed that microwave plasmas can be used to decompose scrap tires into potentially useful liquid products. In a batch experiment using a commercial microwave oven, about 20% of the tire was converted to liquid products in about 9 minutes. Methane was decomposed in a microwave plasma to yield a liquid products composed of various compound types; GC/MS analyses identified unsaturated compounds including benzene, toluene, ethyl benzene, methyl and ethyl naphthalene, small amounts of larger aromatic rings, and olefinic compounds. Experiments on a crude oil in a continuously flowing reactor showed that distillate materials are produced using H and CH plasmas. Also, the recycle oils had an overall carbon aromaticity lower than that of starting feed material, indicating that some hydrogenation and methanation had taken place in the recycle oils.

  20. Introducing constricted variational density functional theory in its relaxed self-consistent formulation (RSCF-CV-DFT) as an alternative to adiabatic time dependent density functional theory for studies of charge transfer transitions

    SciTech Connect (OSTI)

    Krykunov, Mykhaylo; Seth, Mike; Ziegler, Tom

    2014-05-14

    We have applied the relaxed and self-consistent extension of constricted variational density functional theory (RSCF-CV-DFT) for the calculation of the lowest charge transfer transitions in the molecular complex X-TCNE between X = benzene and TCNE = tetracyanoethylene. Use was made of functionals with a fixed fraction (?) of Hartree-Fock exchange ranging from ? = 0 to ? = 0.5 as well as functionals with a long range correction (LC) that introduces Hartree-Fock exchange for longer inter-electronic distances. A detailed comparison and analysis is given for each functional between the performance of RSCF-CV-DFT and adiabatic time-dependent density functional theory (TDDFT) within the Tamm-Dancoff approximation. It is shown that in this particular case, all functionals afford the same reasonable agreement with experiment for RSCF-CV-DFT whereas only the LC-functionals afford a fair agreement with experiment using TDDFT. We have in addition calculated the CT transition energy for X-TCNE with X = toluene, o-xylene, and naphthalene employing the same functionals as for X = benzene. It is shown that the calculated charge transfer excitation energies are in as good agreement with experiment as those obtained from highly optimized LC-functionals using adiabatic TDDFT. We finally discuss the relation between the optimization of length separation parameters and orbital relaxation in the RSCF-CV-DFT scheme.

  1. Studies of Immobilized Homogeneous Metal Catalysts on Silica Supports

    SciTech Connect (OSTI)

    Keith James Stanger

    2003-05-31

    The tethered, chiral, chelating diphosphine rhodium complex, which catalyzes the enantioselective hydrogenation of methyl-{alpha}-acetamidocinnamate (MAC), has the illustrated structure as established by {sup 31}P NMR and IR studies. Spectral and catalytic investigations also suggest that the mechanism of action of the tethered complex is the same as that of the untethered complex in solution. The rhodium complexes, [Rh(COD)H]{sub 4}, [Rh(COD){sub 2}]{sup +}BF{sub 4}{sup -}, [Rh(COD)Cl]{sub 2}, and RhCl{sub 3} {center_dot} 3H{sub 2}O, adsorbed on SiO{sub 2} are optimally activated for toluene hydrogenation by pretreatment with H{sub 2} at 200 C. The same complexes on Pd-SiO{sub 2} are equally active without pretreatments. The active species in all cases is rhodium metal. The catalysts were characterized by XPS, TEM, DRIFTS, and mercury poisoning experiments. Rhodium on silica catalyzes the hydrogenation of fluorobenzene to produce predominantly fluorocyclohexane in heptane and 1,2-dichloroethane solvents. In heptane/methanol and heptane/water solvents, hydrodefluorination to benzene and subsequent hydrogenation to cyclohexane occurs exclusively. Benzene inhibits the hydrodefluorination of fluorobenzene. In DCE or heptane solvents, fluorocyclohexane reacts with hydrogen fluoride to form cyclohexene. Reaction conditions can be chosen to selectively yield fluorocyclohexane, cyclohexene, benzene, or cyclohexane. The oxorhenium(V) dithiolate catalyst [-S(CH{sub 2}){sub 3}s-]Re(O)(Me)(PPh{sub 3}) was modified by linking it to a tether that could be attached to a silica support. Spectroscopic investigation and catalytic oxidation reactivity showed the heterogenized catalyst's structure and reactivity to be similar to its homogeneous analog. However, the immobilized catalyst offered additional advantages of recyclability, extended stability, and increased resistance to deactivation.

  2. Functionalization/passivation of porous graphitic carbon with di-tert-amylperoxide

    SciTech Connect (OSTI)

    Jensen, David S.; Gupta, Vipul; Olsen, Rebecca E.; Miller, Alex T.; Davis, Robert C.; Ess, Daniel; Zhu, Zihua; Vail, Michael A.; Dadson, Andrew; Linford, Matthew R.

    2011-11-18

    Porous graphitic carbon (PGC) particles were functionalized/passivated in situ in packed beds at elevated temperature with neat di-tert-amylperoxide (DTAP) in a column oven. The performance of these particles for high performance liquid chromatography (HPLC) was assayed before and after this chemistry with the following analytes: benzene, toluene, ethyl benzene, n-propyl benzene, n-butyl benzene, p-xylene, phenol, 4-methylphenol, phenetole, 3,5-xylenol, and anisole. After the first functionalization/passivation, the retention factors, k, of these compounds decreased by about 5% and the number of theoretical plates (N) increased by ca. 15%. These values of k then remained roughly constant after a second functionalization/ passivation but a further increase in N was noticed. In addition, after each of the reactions, the peak asymmetries decreased by ca. 15%, for a total of ca. 30%. The columns were then subjected twice to methanol at 100 C for 5 h at 1 mL/min. After these stability tests, the values of k remained roughly constant, the number of plates increased, which is favorable, and the asymmetries rose and then declined, where they remained below the initial values for the unfunctionalized columns. Functionalized and unfunctionalized particles were characterized by scanning electron microscopy and BET measurements, which showed no difference between the functionalized and unfunctionalized materials, and X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS), where ToF-SIMS suggested some chemical differences between the functionalized and unfunctionalized materials. In particular ToF-SIMS suggested that the expected five-carbon fragments from DTAP exist at higher concentrations on DTAP-functionalized PGC. First principle calculations on model graphitic surfaces suggest that the first addition of a DTAP radical to the surface proceeds in an approximately isothermal or slightly favorable fashion, but that subsequent DTAP additions are then increasingly thermodynamically favorable. Thus, this analysis suggests that the direct functionalization/passivation of PGC with DTAP is plausible. Chemometric analyses of the chromatographic and ToF-SIMS data are also presented.

  3. Source Term Modeling for Evaluating the Potential Impacts to Groundwater of Fluids Escaping from a Depleted Oil Reservoir Used for Carbon Sequestration

    SciTech Connect (OSTI)

    Cantrell, Kirk J.; Brown, Christopher F.

    2014-06-13

    In recent years depleted oil reservoirs have received special interest as carbon storage reservoirs because of their potential to offset costs through collaboration with enhanced oil recovery projects. Modeling is currently being conducted to evaluate potential risks to groundwater associated with leakage of fluids from depleted oil reservoirs used for storage of CO2. Modeling results reported here focused on understanding how toxic organic compounds found in oil will distribute between the various phases within a storage reservoir after introduction of CO2, understanding the migration potential of these compounds, and assessing potential groundwater impacts should leakage occur. Two model scenarios were conducted to evaluate how organic components in oil will distribute among the phases of interest (oil, CO2, and brine). The first case consisted of 50 wt.% oil and 50 wt.% water; the second case was 90 wt.% CO2 and 10 wt.% oil. Several key organic compounds were selected for special attention in this study based upon their occurrence in oil at significant concentrations, relative toxicity, or because they can serve as surrogate compounds for other more highly toxic compounds for which required input data are not available. The organic contaminants of interest (COI) selected for this study were benzene, toluene, naphthalene, phenanthrene, and anthracene. Partitioning of organic compounds between crude oil and supercritical CO2 was modeled using the Peng-Robinson equation of state over temperature and pressure conditions that represent the entire subsurface system (from those relevant to deep geologic carbon storage environments to near surface conditions). Results indicate that for a typical set of oil reservoir conditions (75°C, and 21,520 kPa) negligible amounts of the COI dissolve into the aqueous phase. When CO2 is introduced into the reservoir such that the final composition of the reservoir is 90 wt.% CO2 and 10 wt.% oil, a significant fraction of the oil dissolves into the vapor phase. As the vapor phase moves up through the stratigraphic column, pressures and temperatures decrease, resulting in significant condensation of oil components. The heaviest organic components condense early in this process (at higher pressures and temperatures), while the lighter components tend to remain in the vapor phase until much lower pressures and temperatures are reached. Based on the model assumptions, the final concentrations of COI to reach an aquifer at 1,520 kPa and 25°C were quite significant for benzene and toluene, whereas the concentrations of polynuclear aromatic hydrocarbons that reach the aquifer were very small. This work demonstrates a methodology that can provide COI source term concentrations in CO2 leaking from a reservoir and entering an overlying aquifer for use in risk assessments.

  4. SYNTHESIS OF THE FULLY PROTECTED PHOSPHORAMIDITE OF THE BENZENE-DNA ADDUCT, N2- (4-HYDROXYPHENYL)-2'-DEOXYGUANOSINE AND INCORPORATION OF THE LATER INTO DNA OLIGOMERS

    SciTech Connect (OSTI)

    Chenna, Ahmed; Gupta, Ramesh C.; Bonala, Radha R.; Johnson, Francis; Huang, Bo

    2008-06-09

    N2-(4-Hydroxyphenyl)-2'-deoxyguanosine-5'-O-DMT-3'-phosphoramidite has been synthesized and used to incorporate the N2-(4-hydroxyphenyl)-2'-dG (N2-4-HOPh-dG) into DNA, using solid-state synthesis technology. The key step to obtaining the xenonucleoside is a palladium (Xantphos-chelated) catalyzed N2-arylation (Buchwald-Hartwig reaction) of a fully protected 2'-deoxyguanosine derivative by 4-isobutyryloxybromobenzene. The reaction proceeded in good yield and the adduct was converted to the required 5'-O-DMT-3'-O-phosphoramidite by standard methods. The latter was used to synthesize oligodeoxynucleotides in which the N2-4-HOPh-dG adduct was incorporated site-specifically. The oligomers were purified by reverse-phase HPLC. Enzymatic hydrolysis and HPLC analysis confirmed the presence of this adduct in the oligomers.

  5. Process for the production of ethylene and other hydrocarbons from coal

    DOE Patents [OSTI]

    Steinberg, M.; Fallon, P.

    1984-02-15

    The subject invention comprises the steps of first reacting particulate coal with methane at a temperature in the approximate range of 500/sup 0/C to 1100/sup 0/C and at a partial pressure of methane of less than about 200 psig for a period of less than 10 seconds. More preferably, the method of the subject invention is carried out at a temperature of approximately 850/sup 0/C to 1000/sup 0/C and a pressure of 50 psig for a period of approximately 1.5 seconds. Surprisingly, it has been found that in the practice of the subject invention not only are commercially significant quantities of ethylene produced, namely yields in excess of 10% (percent carbon converted to product), along with economically significant quantities of-benzene and light oils, namely toluene and xylene, but also that there is little, if any, net consumption of methane in the reaction and possibly even a small net production. Since it is apparent that the carbonaceous solids or char remaining after the reaction is carried out may be burned to provide the necessary energy to carry out the process of the subject invention, it is apparent that the subject invention advantageously provides a method for the conversion of coal to economically significant quantities of ethylene, benzene and light oils while requiring only coal and, possibly, small amounts of make-up methane. Other objects and advantages of the subject invention will be apparent to those skilled in the art from a consideration of the attached drawings, the detailed description of the invention, and the experimental examples set forth below.

  6. Flash methanolysis of wood for the production of fuels and chemicals

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.T.; Sundaram, M.S.

    1983-01-01

    Biomass in the form of less than 1000 micron oven dried fir wood particles was flash pyrolyzed in the presence of methane (methanolysis) in a downflow 1 in. I.D. tubular reactor at pressures of 20 to 200 psi and temperatures between 800/sup 0/ and 1050/sup 0/C. The major products were benzene, toluene and xylene (BTX), a heavy oily liquid (greater than or equal to C/sub 9/), ethylene and carbon monoxide. As much as 12% of the available carbon in the wood was converted to BTX, 21% to ethylene and 48% to carbon monoxide at 50 psi and 1000/sup 0/C. The maximum heavier oil yield of 11% was observed at 50 psi and 800/sup 0/C. Wood particle residence times for all experiments were calculated to be less than 1 second at 20 and 50 psi and up to 2.8 sec at 200 psi. The yelds were found to be greatly influenced by the methane to wood feed ratio. Experiments were conducted to insure the results to be that produced from the wood and methane and not a catalytic effect of the reactor wall of foreign matter. Material balance, including char analyses, indicate approximately 75 to 80% of the available carbon in the feed wood reacted. Methane balances were within the margin of error of the measuring equipment showing that there is no significant net production or consumption of methane. A preliminary economic evaluation of a 2000 ton/day wood processing plant producing ethylene, benzene and methanol showed a reasonably cmpetitive plant investment of $29,000/barrel fuel oil equivalent/day assuming 15% return on investment and present market values for the products.

  7. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect (OSTI)

    Ramanathan Sampath

    2004-03-31

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period October 01, 2003 to March 31, 2004 which covers the third six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. During this reporting period, temperature scans were performed mixing equal volumes of ethylbenzene and 10mM NaCl water with various concentrations of ethanol ranging from 2 to 70 vol%. For the range of temperatures tested (2 to 70 C), results indicate that temperature is invariant and produced a single phase for ethanol concentrations greater than 60 vol%. For ethanol concentrations less than 60 vol%, only two phases were obtained with aqueous rich bottom phase more in volume than that of the ethylbenzene rich top phase. Linear coreflooding experiments were completed by our industrial partner in this project, Surtek, CO, to measure the condensate recovery in flooding processes. It was found about 30% ethylbenzene recovery was obtained by the waterflooding, however, 2wt% ethanol flooding did not produce incremental recovery of the ethylbenzene. Radial coreflooding with ethanol injection prior to water injection is in progress to assess the effectiveness of the surfactant flooding in the recovery of condensate.

  8. Superfund Record of Decision (EPA Region 7): John Deere DDubuque Works, Dubuque, Iowa (first remedial action), September 1988. Final report

    SciTech Connect (OSTI)

    Not Available

    1988-09-29

    The John Deere Dubuque Works site is located approximately 2.5 miles north of the City of Dubuque, Iowa. The site is owned by Deere and Company, which has operated a manufacturing plant at the site since 1946. The plant property includes an area of 1,447 acres located in the flood plain at the confluence of the Little Maquoketa River and the Mississippi River. The waste-management history of the plant is complex, but the primary area of concern is an unlined landfill originally placed in a natural depression caused by the Little Maquoketa River. Prior to 1968, wastes were placed in the low areas of the landfill and combustible materials were burned. Another area of concern at the facility is the site of a 1980, 200,000-gallon diesel fuel spill. Investigations conducted by John Deere indicated that human health hazards at the landfill could be considered minimal with the primary hazard being the possibility of dissolved organic chemicals impacting offsite domestic wells located east of the plant along the Mississippi River. The primary contaminants of concern affecting the ground water are volatile organic compounds including benzene, PCE, TCE, and toluene. The selected remedial action for the site is included.

  9. Source profiles for nonmethane organic compounds in the atmosphere of Cairo, Egypt.

    SciTech Connect (OSTI)

    Doskey, P. V.; Fukui, Y.; Sultan, M.; Maghraby, A. A.; Taher, A.; Environmental Research; Cairo Univ.

    1999-07-01

    Profiles of the sources of nonmethane organic compounds (NMOCs) were developed for emissions from vehicles, petroleum fuels (gasoline, liquefied petroleum gas (LPG), and natural gas), a petroleum refinery, a smelter, and a cast iron factory in Cairo, Egypt. More than 100 hydrocarbons and oxygenated hydrocarbons were tentatively identified and quantified. Gasoline-vapor and whole-gasoline profiles could be distinguished from the other profiles by high concentrations of the C{sub 5} and C{sub 6} saturated hydrocarbons. The vehicle emission profile was similar to the whole-gasoline profile, with the exception of the unsaturated and aromatic hydrocarbons, which were present at higher concentrations in the vehicle emission profile. High levels of the C{sub 2}-C{sub 4} saturated hydrocarbons, particularly n-butane, were characteristic features of the petroleum refinery emissions. The smelter and cast iron factory emissions were similar to the refinery emissions; however, the levels of benzene and toluene were greater in the former two sources. The LPG and natural gas emissions contained high concentrations of n-butane and ethane, respectively. The NMOC source profiles for Cairo were distinctly different from profiles for U.S. sources, indicating that NMOC source profiles are sensitive to the particular composition of petroleum fuels that are used in a location.

  10. Application and results of whole-body autoradiography in distribution studies of organic solvents

    SciTech Connect (OSTI)

    Bergman, K.

    1983-01-01

    With the growing concern for the health hazards of occupational exposure to toxic substances attention has been focused on the organic solvents, which are associated with both deleterious nervous system effects and specific tissue injuries. Relatively little is known about the distribution of organic solvents and their metabolites in the living organism. Knowledge of the specific tissue localizations and retention of solvents and solvent metabolites is of great value in revealing and understanding the sites and mechanisms of organic solvent toxicity. Whole-body autoradiography has been modified and applied to distribution studies of benzene, toluene, m-xylene, styrene, methylene chloride, chloroform, carbon tetrachloride, trichloroethylene and carbon disulfide. The high volatility of these substances has led to the development of cryo-techniques. Whole-body autoradiographic techniques applicable to the study of volatile substances are reviewed. The localizations of nonvolatile solvent metabolites and firmly bound metabolites have also been examined. The obtained results are discussed in relation to toxic effects and evaluated by comparison with other techniques used in distribution studies of organic solvents and their metabolites.

  11. Furan production from glycoaldehyde over HZSM-5

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kim, Seonah; Evans, Tabitha J.; Mukarakate, Calvin; Bu, Lintao; Beckham, Gregg T.; Nimlos, Mark R.; Paton, Robert S.; Robichaud, David J.

    2016-04-03

    Catalytic fast pyrolysis of biomass over zeolite catalysts results primarily in aromatic (e.g. benzene, toluene, xylene) and olefin products. However, furans are a higher value intermediate for their ability to be readily transformed into gasoline, diesel, and chemicals. Here we investigate possible mechanisms for the coupling of glycoaldehyde, a common product of cellulose pyrolysis, over HZSM-5 for the formation of furans. Experimental measurements of neat glycoaldehyde over a fixed bed of HZSM-5 confirm furans (e.g. furanone) are products of this reaction at temperatures below 300 degrees C with several aldol condensation products as co-products (e.g. benzoquinone). However, under typical catalyticmore » fast pyrolysis conditions (>400 degrees C), further reactions occur that lead to the usual aromatic product slate. ONIOM calculations were utilized to identify the pathway for glycoaldehyde coupling toward furanone and hydroxyfuranone products with dehydration reactions serving as the rate determining steps with typical intrinsic reaction barriers of 40 kcal mol-1. The reaction mechanisms for glycoaldehyde will likely be similar to that of other small oxygenates such as acetaldehyde, lactaldehyde, and hydroxyacetone and this study provides a generalizable mechanism of oxygenate coupling and furan formation over zeolite catalysts.« less

  12. Vapor Sensing Using Conjugated Molecule-Linked Au Nanoparticles in a Silica Matrix

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dirk, Shawn M.; Howell, Stephen W.; Price, B. Katherine; Fan, Hongyou; Washburn, Cody; Wheeler, David R.; Tour, James M.; Whiting, Joshua; Simonson, R. Joseph

    2009-01-01

    Cross-linkedmore » assemblies of nanoparticles are of great value as chemiresistor-type sensors. Herein, we report a simple method to fabricate a chemiresistor-type sensor that minimizes the swelling transduction mechanism while optimizing the change in dielectric response. Sensors prepared with this methodology showed enhanced chemoselectivity for phosphonates which are useful surrogates for chemical weapons. Chemoselective sensors were fabricated using an aqueous solution of gold nanoparticles that were then cross-linked in the presence of the silica precursor, tetraethyl orthosilicate with the α -, ω -dithiolate (which is derived from the in situ deprotection of 1,4-di(Phenylethynyl- 4 ′ , 4 ″ -diacetylthio)-benzene ( 1 ) with wet triethylamine). The cross-linked nanoparticles and silica matrix were drop coated onto interdigitated electrodes having 8  μ m spacing. Samples were exposed to a series of analytes including dimethyl methylphosphonate (DMMP), octane, and toluene. A limit of detection was obtained for each analyte. Sensors assembled in this fashion were more sensitive to dimethyl methylphosphonate than to octane by a factor of 1000.« less

  13. Pyrolysis of scrap tires: Can it be profitable?

    SciTech Connect (OSTI)

    Wojtowicz, M.A.; Serio, M.A.

    1996-10-01

    Pyrolysis--the thermal degradation in the absence of oxygen--is one way to reprocess scrap tires. The products are fuel gas, oils, and a solid residue (char), which contains appreciable quantities of mineral matter and low-grade carbon black. The three products have comparable yields by weight. The two most important factors affecting process economics are the tipping fees charged for tire disposal and the selling prices of the products. Selling prices of the products yield low returns because of the low market value of the fuels and the low quality of the recovered char or carbon black. Therefore, to obtain a positive cash flow, it would be desirable to develop a process based on the recovery of value-added products such as high-grade carbon black, activated carbon, or valuable chemicals (e.g., benzene, toluene, and xylene). The authors believe that significant improvement in the economics can be accomplished by upgrading the primary pyrolysis products to secondary products of higher value.

  14. A Feasibility Study for Recycling Used Automotive Oil Filters In A Blast Furnace

    SciTech Connect (OSTI)

    Ralph M. Smailer; Gregory L. Dressel; Jennifer Hsu Hill

    2002-01-21

    This feasibility study has indicated that of the approximately 120,000 tons of steel available to be recycled from used oil filters (UOF's), a maximum blast furnace charge of 2% of the burden may be anticipated for short term use of a few months. The oil contained in the most readily processed UOF's being properly hot drained and crushed is approximately 12% to 14% by weight. This oil will be pyrolized at a rate of 98% resulting in additional fuel gas of 68% and a condensable hydrocarbon fraction of 30%, with the remaining 2% resulting as carbon being added into the burden. Based upon the writer's collected information and assessment, there appears to be no operational problems relating to the recycling of UOF's to the blast furnace. One steel plant in the US has been routinely charging UOF's at about 100 tons to 200 tons per month for many years. Extensive analysis and calculations appear to indicate no toxic consideration as a result of the pyrolysis of the small contained oil ( in the 'prepared' UOFs) within the blast furnace. However, a hydrocarbon condensate in the ''gasoline'' fraction will condense in the blast furnace scrubber water and may require additional processing the water treatment system to remove benzene and toluene from the condensate. Used oil filters represent an additional source of high quality iron units that may be effectively added to the charge of a blast furnace for beneficial value to the operator and to the removal of this resource from landfills.

  15. PREPARATION OF ALKYL PYROPHOSPHATE EXTRACTANTS

    DOE Patents [OSTI]

    Levine, C.A.; Skiens, W.E.; Moore, G.R.

    1960-08-01

    A process for providing superior solvent extractants for metal recovery processes is given wherein the extractant comprises an alkyl pyrophosphoric acid ester dissolved in an organic solvent diluent. Finely divided solid P/sub 2/O/ sub 5/ is slurried in an organic solvent-diluent selected from organic solvents such as kerosene, benzene, chlorobenzene, toluene, etc. An alcohol selected from the higher alcohols having 4 to 17 carbon atoms. e.g.. hexanol-1. heptanol-3, octanol-1. 2.6-dimethyl-heptanol-4, and decanol-1, is rapidly added to the P/sub 2/O/sub 5/ slurry in the amount of about 2 moles of alcohol to 1 mole of P/sub 2/ O/sub 5/. The temperature is maintained below about 110 deg C during the course of the P/sub 2/O/sub 5/-alcohol reaction. An alkyl pyrophosphate extractant compound is formed as a consequence of the reaction process. The alkyl pyrophosphate solvent-diluent extractant phase is useful in solvent extraction metal recovery processes.

  16. Superfund Record of Decision (EPA Region 7): Vogel Paint and Wax, Maurice, IA. (First remedial action), September 1989. Final report

    SciTech Connect (OSTI)

    Not Available

    1989-09-20

    The Vogel Paint and Wax (VPW) site is an approximately two-acre disposal area two miles southwest of the town of Maurice, in Sioux County, Iowa. Adjacent land uses are primarily agricultural; however, several private residences are within one-quarter mile of the site. A surficial sand and gravel aquifer underlies the site and supplies nearby private wells and the Southern Sioux County Rural Water System, located a mile and one half southeast of the site. Paint sludge, resins, solvents, and other paint-manufacturing wastes were disposed of at the site between 1971 and 1979. VPW records indicate that approximately 43,000 gallons of aliphatic and aromatic hydrocarbons and 6,000 pounds of metals waste were buried at the site. The primary contaminants of concern affecting the soil and ground water are VOCs including benzene, toluene, and xylenes; and metals including chromium and lead. The selected remedial action for this site includes excavation of contaminated soil and separation of solid and liquid wastes; onsite bioremediation of 3,000 cubic yards of the contaminated soil in a fully contained surface impoundment unit, or onsite thermal treatment if soil contains high metal content; and stabilization of treated soil, if necessary to prevent leaching of metals, followed by disposal in the excavated area.

  17. Photophysics and Luminescence Spectroelectrochemistry of [Tc(dmpe)3]+/2+ (dmpe = 1,2-bis(dimethylphosphino)ethane)

    SciTech Connect (OSTI)

    Chatterjee, Sayandev; Del Negro, Andrew S.; Smith, Frances N.; Wang, Zheming; Hightower, Sean E.; Sullivan, Brian P.; Heineman, William R.; Seliskar, Carl J.; Bryan, Samuel A.

    2013-12-05

    The ligand-to-metal charge transfer (LMCT) excited state luminescence of [Tc(dmpe)3]2+ (dmpe is 1,2-bis-(dimethylphosphino)ethane) has been measured in solution at room temperature, and is compared to its Re analogue. Surprisingly, both [M(dmpe)3]2+* (M = Re, Tc) species have extremely large excited-state potentials (ESPs) as oxidants - the highest for any simple coordination complex of a transition metal. Furthermore, this potential is available using a photon of visible light (calculated for M = Re(Tc); E1/2* = +2.61(2.48) V versus SCE; ?max = 526(585) nm). Open shell TDDFT calculations support the assignment of the lowest energy transition in both the technetium and rhenium complexes to be a doublet-doublet process that involve predominantly LMCT (dmpe-to-metal) character and is in agreement with past assignments for the Re system. As expected for highly oxidizing excited state potentials, quenching is observed for the excited states by both the rhenium and technetium complexes. Stern-Volmer analysis resulted in quenching parameters for both the rhenium and technetium complexes under identical conditions, and are compared using Rehm-Weller analysis. Of particular interest is the fact that both benzene and toluene are oxidized by both the Re and Tc systems.

  18. Reformulated Gasoline Complex Model

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    ... However, nonexhaust benzene emissions data are only available in sufficient quantities under high ozone test conditions. Therefore, nonexhaust benzene emissions are not considered ...

  19. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, Narayan; Ingersoll, David

    1995-01-01

    Electrolytes for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids.

  20. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, N.; Ingersoll, D.

    1995-01-03

    Electrolytes are disclosed for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids. 7 figures.

  1. Effect of uncertain hydraulic conductivity on the fate and transport of BTEX compounds at a field site

    SciTech Connect (OSTI)

    Lu, Guoping; Zheng, Chunmiao; Wolfsberg, Andrew

    2002-01-05

    A Monte Carlo analysis was conducted to investigate the effect of uncertain hydraulic conductivity on the fate and transport of BTEX compounds (benzene, toluene, ethyl benzene, and xylene) at a field site on Hill Air Force Base, Utah. Microbially mediated BTEX degradation has occurred at the site through multiple terminal electron-accepting processes, including aerobic respiration, denitrification, Fe(III) reduction, sulfate reduction, and methanogenesis degradation. Multiple realizations of the hydraulic conductivity field were generated and substituted into a multispecies reactive transport model developed and calibrated for the Hill AFB site in a previous study. Simulation results show that the calculated total BTEX masses (released from a constant-concentration source) that remain in the aquifer at the end of the simulation period statistically follow a lognormal distribution. In the first analysis (base case), the calculated total BTEX mass varies from a minimum of 12% less and a maximum of 60% more than that of the previously calibrated model. This suggests that the uncertainty in hydraulic conductivity can lead to significant uncertainties in modeling the fate and transport of BTEX. Geometric analyses of calculated plume configurations show that a higher BTEX mass is associated with wider lateral spreading, while a lower mass is associated with longer longitudinal extension. More BTEX mass in the aquifer causes either a large depletion of dissolved oxygen (DO) and NO{sub 3}{sup -}, or a large depletion of DO and a large production of Fe{sup 2+}, with moderately depleted NO{sub 3}{sup -}. In an additional analysis, the effect of varying degrees of aquifer heterogeneity and associated uncertainty is examined by considering hydraulic conductivity with different variances and correlation lengths. An increase in variance leads to a higher average BTEX mass in the aquifer, while an increase in correlation length results in a lower average. This observation is explained by relevant partitioning of BTEX into the aquifer from the LNAPL source. Although these findings may only be applicable to the field conditions considered in this study, the methodology used and insights gained are of general interest and relevance to other fuel-hydrocarbon natural-attenuation sites.

  2. SALTSTONE VAULT CLASSIFICATION SAMPLES MODULAR CAUSTIC SIDE SOLVENT EXTRACTION UNIT/ACTINIDE REMOVAL PROCESS WASTE STREAM APRIL 2011

    SciTech Connect (OSTI)

    Eibling, R.

    2011-09-28

    Savannah River National Laboratory (SRNL) was asked to prepare saltstone from samples of Tank 50H obtained by SRNL on April 5, 2011 (Tank 50H sampling occurred on April 4, 2011) during 2QCY11 to determine the non-hazardous nature of the grout and for additional vault classification analyses. The samples were cured and shipped to Babcock & Wilcox Technical Services Group-Radioisotope and Analytical Chemistry Laboratory (B&W TSG-RACL) to perform the Toxic Characteristic Leaching Procedure (TCLP) and subsequent extract analysis on saltstone samples for the analytes required for the quarterly analysis saltstone sample. In addition to the eight toxic metals - arsenic, barium, cadmium, chromium, mercury, lead, selenium and silver - analytes included the underlying hazardous constituents (UHC) antimony, beryllium, nickel, and thallium which could not be eliminated from analysis by process knowledge. Additional inorganic species determined by B&W TSG-RACL include aluminum, boron, chloride, cobalt, copper, fluoride, iron, lithium, manganese, molybdenum, nitrate/nitrite as Nitrogen, strontium, sulfate, uranium, and zinc and the following radionuclides: gross alpha, gross beta/gamma, 3H, 60Co, 90Sr, 99Tc, 106Ru, 106Rh, 125Sb, 137Cs, 137mBa, 154Eu, 238Pu, 239/240Pu, 241Pu, 241Am, 242Cm, and 243/244Cm. B&W TSG-RACL provided subsamples to GEL Laboratories, LLC for analysis for the VOCs benzene, toluene, and 1-butanol. GEL also determines phenol (total) and the following radionuclides: 147Pm, 226Ra and 228Ra. Preparation of the 2QCY11 saltstone samples for the quarterly analysis and for vault classification purposes and the subsequent TCLP analyses of these samples showed that: (1) The saltstone waste form disposed of in the Saltstone Disposal Facility in 2QCY11 was not characteristically hazardous for toxicity. (2) The concentrations of the eight RCRA metals and UHCs identified as possible in the saltstone waste form were present at levels below the UTS. (3) Most of the inorganic species measured in the leachate do not exceed the MCL, SMCL or TW limits. (4) The inorganic waste species that exceeded the MCL by more than a factor of 10 were nitrate, nitrite and the sum of nitrate and nitrite. (5) Analyses met all quality assurance specifications of US EPA SW-846. (6) The organic species (benzene, toluene, 1-butanol, phenol) were either not detected or were less than reportable for the vault classification samples. (7) The gross alpha and radium isotopes could not be determined to the MCL because of the elevated background which raised the detection limits. (8) Most of the beta/gamma activity was from 137Cs and its daughter 137mBa. (9) The concentration of 137Cs and 90Sr were present in the leachate at concentrations 1/40th and 1/8th respectively than in the 2003 vault classification samples. The saltstone waste form placed in the Saltstone Disposal Facility in 2QCY11 met the SCHWMR R.61-79.261.24(b) RCRA metals requirements for a nonhazardous waste form. The TCLP leachate concentrations for nitrate, nitrite and the sum of nitrate and nitrite were greater than 10x the MCLs in SCDHEC Regulations R.61-107.19, Part I A, which confirms the Saltstone Disposal Facility classification as a Class 3 Landfill. The saltstone waste form placed in the Saltstone Disposal Facility in 2QCY11 met the R.61-79.268.48(a) non wastewater treatment standards.

  3. Synthesis metal nanoparticle

    DOE Patents [OSTI]

    Bunge, Scott D.; Boyle, Timothy J.

    2005-08-16

    A method for providing an anhydrous route for the synthesis of amine capped coinage-metal (copper, silver, and gold) nanoparticles (NPs) using the coinage-metal mesityl (mesityl=C.sub.6 H.sub.2 (CH.sub.3).sub.3 -2,4,6) derivatives. In this method, a solution of (Cu(C.sub.6 H.sub.2 (CH.sub.3).sub.3).sub.5, (Ag(C.sub.6 H.sub.2 (CH.sub.3).sub.3).sub.4, or (Au(C.sub.6 H.sub.2 (CH.sub.3).sub.3).sub.5 is dissolved in a coordinating solvent, such as a primary, secondary, or tertiary amine; primary, secondary, or tertiary phosphine, or alkyl thiol, to produce a mesityl precursor solution. This solution is subsequently injected into an organic solvent that is heated to a temperature greater than approximately 100.degree. C. After washing with an organic solvent, such as an alcohol (including methanol, ethanol, propanol, and higher molecular-weight alcohols), oxide free coinage NP are prepared that could be extracted with a solvent, such as an aromatic solvent (including, for example, toluene, benzene, and pyridine) or an alkane (including, for example, pentane, hexane, and heptane). Characterization by UV-Vis spectroscopy and transmission electron microscopy showed that the NPs were approximately 9.2.+-.2.3 nm in size for Cu.degree., (no surface oxide present), approximately 8.5.+-.1.1 nm Ag.degree. spheres, and approximately 8-80 nm for Au.degree..

  4. Non-Aqueous Phase Liquid Calculator

    Energy Science and Technology Software Center (OSTI)

    2004-02-19

    Non-Aqueous Phase Liquid or "NPAL" is a term that most environmental professionals are familiar with because NAPL has been recognized in the literature as a significant source of groundwater contamination. There are two types of NAPL: DNAPL and LNAPL. DNAPL is a ‘dense’ non-aqueous phase liquid. In this context, dense means having a density greater than water (1.0 kg/L). Trichloroethylene (TCE) and tetrachioroethylene (PCE) are examples of DNAPL compounds. A compound that is heaver thanmore » water means this type of NAPL will sink in an aquifer. Conversely, LNAPL is a ‘light’ non-aqueous phase liquid with a density less than water, and will float on top of the aquifer. Examples of LNAPL’s are benzene and toluene. LNAPL or DNAPL often manifest as a complex, multi-component mixture of organic compounds that can occur in environmental media. Complex multi-component mixtures distributed in soil pore-air, pore-water, soil particles and in free phase complicate residual saturation of single and multi component NAPL compounds in soil samples. The model output also includes estimates of the NAPL mass and volume and other physical and chemical properties that may be useful for characterization, modeling, and remedial system design and operation. The discovery of NAPL in the aquifer usually leads to a focused characterization for possible sources of NAPL in the vadose zone using a variety of innovative technologies and characterization methods. Often, the analytical data will indicated the presence of NAPL, yet, the NAPL will go unrecognized. Failure to recognize the NAPL can be attributed to the complicated processes of inter-media transfer or a general lack of knowledge about the physical characteristics of complex organic mixtures in environmental samples.« less

  5. TREATMENT OF PRODUCED OIL AND GAS WATERS WITH SURFACTANT-MODIFIED ZEOLITE

    SciTech Connect (OSTI)

    Lynn E. Katz; R.S. Bowman; E.J. Sullivan

    2003-11-01

    Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. It is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some must be treated to remove organic constituents before the water is discharged. Current treatment options are successful in reducing the organic content; however, they cannot always meet the levels of current or proposed regulations for discharged water. Therefore, an efficient, cost-effective treatment technology is needed. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. This report summarizes the work and results of this four-year project. We tested the effectiveness of surfactant-modified zeolite (SMZ) for removal of BTEX with batch and column experiments using waters with BTEX concentrations that are comparable to those of produced waters. The data from our experimental investigations showed that BTEX sorption to SMZ can be described by a linear isotherm model, and competitive effects between compounds were not significant. The SMZ can be readily regenerated using air stripping. We field-tested a prototype SMZ-based water treatment system at produced water treatment facilities and found that the SMZ successfully removes BTEX from produced waters as predicted by laboratory studies. When compared to other existing treatment technologies, the cost of the SMZ system is very competitive. Furthermore, the SMZ system is relatively compact, does not require the storage of potentially hazardous chemicals, and could be readily adapted to an automated system.

  6. Compounds for neutron radiation detectors and systems thereof

    DOE Patents [OSTI]

    Payne, Stephen A; Stoeffl, Wolfgang; Zaitseva, Natalia P; Cherepy, Nerine J; Carman, M. Leslie

    2014-05-27

    A material according to one embodiment exhibits an optical response signature for neutrons that is different than an optical response signature for gamma rays, said material exhibiting performance comparable to or superior to stilbene in terms of distinguishing neutrons from gamma rays, wherein the material is not stilbene, the material comprising a molecule selected from a group consisting of: two or more benzene rings, one or more benzene rings with a carboxylic acid group, one or more benzene rings with at least one double bound adjacent to said benzene ring, and one or more benzene rings for which at least one atom in the benzene ring is not carbon.

  7. "Title","Creator/Author","Publication Date","OSTI Identifier...

    Office of Scientific and Technical Information (OSTI)

    BENZENE; LEUKEMOGENESIS; GEOTHERMAL INDUSTRY; ENVIRONMENTAL IMPACTS; HEALTH HAZARDS; HYDROGEN SULFIDES; BIOLOGICAL EFFECTS; MERCURY; RADON; SULFATES; ACCIDENTS; AIR POLLUTION;...

  8. TITLE AUTHORS SUBJECT SUBJECT RELATED DESCRIPTION PUBLISHER AVAILABILI...

    Office of Scientific and Technical Information (OSTI)

    BENZENE LEUKEMOGENESIS GEOTHERMAL INDUSTRY ENVIRONMENTAL IMPACTS HEALTH HAZARDS HYDROGEN SULFIDES BIOLOGICAL EFFECTS MERCURY RADON SULFATES ACCIDENTS AIR POLLUTION...

  9. Layton, D.W.; Anspaugh, L.R.; O'Banion, K.D. 15 GEOTHERMAL ENERGY...

    Office of Scientific and Technical Information (OSTI)

    BENZENE; LEUKEMOGENESIS; GEOTHERMAL INDUSTRY; ENVIRONMENTAL IMPACTS; HEALTH HAZARDS; HYDROGEN SULFIDES; BIOLOGICAL EFFECTS; MERCURY; RADON; SULFATES; ACCIDENTS; AIR POLLUTION;...

  10. CH

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Toluene is readily identified on the HOPG basal surface after the nonresonant sum frequency generation (SFG) signal is readily suppressed using time-delay methods enabled by femtosecond laser pulses. The signature CH 3 vibrational modes of toluene are resolved as exemplified by the black trace above. The molecular orientation of toluene from the surface normal is easily determined at the HOPG surface by employing the Polarization Null Angle Technique to triangulate position of the C3v symmetric

  11. Poly(ethylene oxide) functionalization (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    The polymer is dissolved in warmed toluene, treated with an excess of organic base and ... This procedure enables functionalization of the polymer while not requiring laborious ...

  12. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... less Full Text Available April 2008 , Health Physics http:www.ncbi.nlm.nih.govpubmed18332729 Evaluation of a Polyvinyl Toluene Neutron Counter Array Robert Hayes The ...

  13. Preliminary Evaluation of a Portable Handheld Combined Gamma...

    Office of Scientific and Technical Information (OSTI)

    Experimental procedures: Monte Carlo N-Particle (MCNP) analysis on a compact array of borated polyvinyl toluene light pipes and photomultiplier tubes, standard spectral ...

  14. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    the hydrogenation of other unactivated aromatic hydrocarbons such as toluene, ... EXPERIMENTAL DATA; ORGANOMETALLIC COMPOUNDS; PH VALUE Word Cloud More Like This Full ...

  15. DE-FE0000833

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Toluene 56. Diesel Range Organic C10-C28 57. Ethane 58. Formaldehyde 59. Methane 60. Methanol 61. Alkalinity, Carbonate 62. Alkalinity, Hydroxide 63. Alkalinity, Phenolphthalein...

  16. Cutting Biofuel Production Costs | The Ames Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cutting Biofuel Production Costs Working to use sunlight to convert biomass to biofuels, ... bioderived alcohols to benzaldehyde, toluene, and the zero-emission biofuel hydrogen. ...

  17. Fabrication of Organic-inorganic Perovskites for Highly Efficient...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    solution process-ability at low temperature as well as its extraordinary device performance. ... quality films with the toluene treatment, including high surface coverage, ...

  18. Control of Substrate Access to the Active Site and Catalytic Mechanism of

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Methane and Toluene Monooxygenases | Stanford Synchrotron Radiation Lightsource Control of Substrate Access to the Active Site and Catalytic Mechanism of Methane and Toluene Monooxygenases Friday, June 22, 2012 - 3:30pm SSRL Main Conference Room 137-322 Prof. Stephen J. Lippard (MIT):

  19. ENZYME ACTIVITY PROBE AND GEOCHEMICAL ASSESSMENT FOR POTENTIAL AEROBIC COMETABOLISM OF TRICHLOROETHENE IN GROUNDWATER OF THE NORTHWEST PLUME, PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

    SciTech Connect (OSTI)

    Looney, B; M. Hope Lee, M; S. K. Hampson, S

    2008-06-27

    The overarching objective of the Paducah Gaseous Diffusion Plant (PGDP) enzyme activity probe (EAP) effort is to determine if aerobic cometabolism is contributing to the attenuation of trichloroethene (TCE) and other chlorinated solvents in the contaminated groundwater beneath PGDP. The site-specific objective for the EAP assessment is to identify if key metabolic pathways are present and expressed in the microbial community--namely the pathways that are responsible for degradation of methane and aromatic (e.g. toluene, benzene, phenol) substrates. The enzymes produced to degrade methane and aromatic compounds also break down TCE through a process known as cometabolism. EAPs directly measure if methane and/or aromatic enzyme production pathways are operating and, for the aromatic pathways, provide an estimate of the number of active organisms in the sampled groundwater. This study in the groundwater plumes at PGDP is a major part of a larger scientific effort being conducted by Interstate Technology and Regulatory Council (ITRC), U.S. Department of Energy (DOE) Office of Environmental Management (EM), Savannah River National Laboratory (SRNL), and North Wind Inc. in which EAPs are being applied to contaminated groundwater from diverse hydrogeologic and plume settings throughout the U.S. to help standardize their application as well as their interpretation. While EAP data provide key information to support the site specific objective for PGDP, several additional lines of evidence are being evaluated to increase confidence in the determination of the occurrence of biodegradation and the rate and sustainability of aerobic cometabolism. These complementary efforts include: (1) Examination of plume flowpaths and comparison of TCE behavior to 'conservative' tracers in the plume (e.g., {sup 99}Tc); (2) Evaluation of geochemical conditions throughout the plume; and (3) Evaluation of stable isotopes in the contaminants and their daughter products throughout the plume. If the multiple lines of evidence support the occurrence of cometabolism and the potential for the process to contribute to temporal and spatial attenuation of TCE in PGDP groundwater, then a follow-up enzyme probe microcosm study to better estimate biological degradation rate(s) is warranted.

  20. Study of the VOC emissions from a municipal solid waste storage pilot-scale cell: Comparison with biogases from municipal waste landfill site

    SciTech Connect (OSTI)

    Chiriac, R.; De Araujos Morais, J.; Carre, J.; Bayard, R.; Chovelon, J.M.; Gourdon, R.

    2011-11-15

    Highlights: > Follow-up of the emission of VOCs in a municipal waste pilot-scale cell during the acidogenesis and acetogenesis phases. > Study from the very start of waste storage leading to a better understanding of the decomposition/degradation of waste. > Comparison of the results obtained on the pilot-scale cell with those from 3 biogases coming from the same landfill site. > A methodology of characterization for the progression of the stabilization/maturation of waste is finally proposed. - Abstract: The emission of volatile organic compounds (VOCs) from municipal solid waste stored in a pilot-scale cell containing 6.4 tonnes of waste (storage facility which is left open during the first period (40 days) and then closed with recirculation of leachates during a second period (100 days)) was followed by dynamic sampling on activated carbon and analysed by GC-MS after solvent extraction. This was done in order to know the VOC emissions before the installation of a methanogenesis process for the entire waste mass. The results, expressed in reference to toluene, were exploited during the whole study on all the analyzable VOCs: alcohols, ketones and esters, alkanes, benzenic and cyclic compounds, chlorinated compounds, terpene, and organic sulphides. The results of this study on the pilot-scale cell are then compared with those concerning three biogases from a municipal waste landfill: biogas (1) coming from waste cells being filled or recently closed, biogas (2) from all the waste storage cells on site, and biogas (3) which is a residual gas from old storage cells without aspiration of the gas. The analysis of the results obtained revealed: (i) a high emission of VOCs, principally alcohols, ketones and esters during the acidogenesis; (ii) a decrease in the alkane content and an increase in the terpene content were observed in the VOCs emitted during the production of methane; (iii) the production of heavier alkanes and an increase in the average number of carbon atoms per molecule of alkane with the progression of the stabilisation/maturation process were also observed. Previous studies have concentrated almost on the analysis of biogases from landfills. Our research aimed at gaining a more complete understanding of the decomposition/degradation of municipal solid waste by measuring the VOCs emitted from the very start of the landfill process i.e. during the acidogenesis and acetogenesis phases.

  1. Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

    SciTech Connect (OSTI)

    Jaars, K.; Beukes, J. P.; van Zyl, P. G.; Venter, A. D.; Josipovic, M.; Pienaar, J. J.; Vakkari, Ville; Aaltonen, H.; Laakso, H.; Kulmala, M.; Tiitta, P.; Guenther, Alex B.; Hellen, H.; Laakso, L.; Hakola, H.

    2014-07-11

    Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol that affect human health, crop production and regional climate. Measurements were conducted at the Welgegund measurement station (South Africa) that is considered to be a regionally representative background site. However, the site is occasionally impacted by plumes from major anthropogenic source regions in the interior of South Africa, which include the western Bushveld Igneous Complex (e.g. platinum, base metal and ferrochrome smelters), the eastern Bushveld Igneous Complex (platinum and ferrochrome smelters), the Johannesburg-Pretoria metropolitan conurbation (>10 million people), the Vaal Triangle (e.g. petrochemical and industries), the Mpumalanga Highveld (e.g. coal-fired power plants and petrochemical industry) and also a region of anti-cyclonic recirculation of air mass over the interior of South Africa. The aromatic hydrocarbon measurements were conducted with an automated sampler on Tenax-TA and Carbopack-B adsorbent tubes with heated inlet for one year. Samples were collected twice a week for two hours during daytime and two hours 1 during night-time. A thermal desorption unit, connected to a gas chromatograph and a mass 2 selective detector was used for sample preparation and analysis. Results indicated that the 3 monthly median total aromatic hydrocarbon concentrations ranged between 0.01 to 3.1 ppb. 4 Benzene levels did not exceed local air quality standards. Toluene was the most abundant 5 species, with an annual median concentration of 0.63 ppb. No statistically significant 6 differences in the concentrations measured during daytime and night-time were found and no distinct seasonal patterns were observed. Air mass back trajectory analysis proved that the lack of seasonal cycles could be attributed to patterns determining the origin of the air masses sampled. Aromatic hydrocarbon concentrations were in general significantly higher in air masses that passed over anthropocentrically impacted regions. Interspecies correlations and ratios gave some indications of the possible sources for the different aromatic hydrocarbons in the source regions defined in the paper. The highest contribution of aromatic hydrocarbon concentrations to ozone formation potential was also observed in plumes passing over anthropocentrically impacted regions.

  2. Development of a Hydrogasification Process for Co-Production of Substitute Natural Gas (SNG) and Electric Power from Western Coals

    SciTech Connect (OSTI)

    Sun, Xiaolei; Rink, Nancy

    2011-04-30

    This report presents the results of the research and development conducted on an Advanced Hydrogasification Process (AHP) conceived and developed by Arizona Public Service Company (APS) under U.S. Department of Energy (DOE) contract: DE-FC26-06NT42759 for Substitute Natural Gas (SNG) production from western coal. A double-wall (i.e., a hydrogasification contained within a pressure shell) down-flow hydrogasification reactor was designed, engineered, constructed, commissioned and operated by APS, Phoenix, AZ. The reactor is ASME-certified under Section VIII with a rating of 1150 pounds per square inch gage (psig) maximum allowable working pressure at 1950 degrees Fahrenheit ({degrees}F). The reaction zone had a 1.75 inch inner diameter and 13 feet length. The initial testing of a sub-bituminous coal demonstrated ~ 50% carbon conversion and ~10% methane yield in the product gas under 1625{degrees}F, 1000 psig pressure, with a 11 seconds (s) residence time, and 0.4 hydrogen-to-coal mass ratio. Liquid by-products mainly contained Benzene, Toluene, Xylene (BTX) and tar. Char collected from the bottom of the reactor had 9000-British thermal units per pound (Btu/lb) heating value. A three-dimensional (3D) computational fluid dynamic model simulation of the hydrodynamics around the reactor head was utilized to design the nozzles for injecting the hydrogen into the gasifier to optimize gas-solid mixing to achieve improved carbon conversion. The report also presents the evaluation of using algae for carbon dioxide (CO{sub 2}) management and biofuel production. Nannochloropsis, Selenastrum and Scenedesmus were determined to be the best algae strains for the project purpose and were studied in an outdoor system which included a 6-meter (6M) radius cultivator with a total surface area of 113 square meters (m{sup 2}) and a total culture volume between 10,000 to 15,000 liters (L); a CO{sub 2} on-demand feeding system; an on-line data collection system for temperature, pH, Photosynthetically Activate Radiation (PAR) and dissolved oxygen (DO); and a ~2 gallons per minute (gpm) algae culture dewatering system. Among the three algae strains, Scenedesmus showed the most tolerance to temperature and irradiance conditions in Phoenix and the best self-settling characteristics. Experimental findings and operational strategies determined through these tests guided the operation of the algae cultivation system for the scale-up study. Effect of power plant flue gas, especially heavy metals, on algae growth and biomass adsorption were evaluated as well.

  3. TREATMENT OF PRODUCED WATERS USING A SURFACTANT MODIFIED ZEOLITE/VAPOR PHASE BIOREATOR SYSTEM

    SciTech Connect (OSTI)

    LYNN E. KATZ; KERRY A. KINNEY; R.S. BOWMAN; E.J. SULLIVAN

    2003-10-01

    Co-produced water from the oil and gas industry is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some of them must be treated to remove organic constituents before the water is discharged. An efficient, cost-effective treatment technology is needed to remove these constituents. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. Our previous DOE research work (DE-AC26-99BC15221) demonstrated that SMZ could successfully remove BTEX compounds from the produced water. In addition, SMZ could be regenerated through a simple air sparging process. The primary goal of this project is to develop a robust SMZ/VPB treatment system to efficiently remove the organic constituents from produced water in a cost-effective manner. This report summarizes work of this project from March 2003 through September 2003. We have continued our investigation of SMZ regeneration from our previous DOE project. Ten saturation/stripping cycles have been completed for SMZ columns saturated with BTEX compounds. The results suggest that BTEX sorption capacity is not lost after ten saturation/regeneration cycles. The composition of produced water from a site operated by Crystal Solutions Ltd. in Wyoming has been characterized and was used to identify key semi-volatile components. Isotherms with selected semi-volatile components have been initiated and preliminary results have been obtained. The experimental vapor phase bioreactors for this project have been designed and assembled to treat the off-gas from the SMZ regeneration process. These columns will be used both in the laboratory and in the proposed field testing to be conducted next year. Innocula for the columns that degrade all of the BTEX columns have been developed.

  4. A novel technique for measurement of thermal rate constants and temperature dependences of dissociative recombination: CO{sub 2}{sup +}, CF{sub 3}{sup +}, N{sub 2}O{sup +}, C{sub 7}H{sub 8}{sup +}, C{sub 7}H{sub 7}{sup +}, C{sub 6}H{sub 6}{sup +}, C{sub 6}H{sub 5}{sup +}, C{sub 5}H{sub 6}{sup +}, C{sub 4}H{sub 4}{sup +}, and C{sub 3}H{sub 3}{sup +}

    SciTech Connect (OSTI)

    Fournier, Joseph A.; Shuman, Nicholas S.; Melko, Joshua J.; Ard, Shaun G.; Viggiano, Albert A.

    2013-04-21

    A novel technique using a flowing afterglow-Langmuir probe apparatus for measurement of temperature dependences of rate constants for dissociative recombination (DR) is presented. Low ({approx}10{sup 11} cm{sup -3}) concentrations of a neutral precursor are added to a noble gas/electron afterglow plasma thermalized at 300-500 K. Charge exchange yields one or many cation species, each of which may undergo DR. Relative ion concentrations are monitored at a fixed reaction time while the initial plasma density is varied between 10{sup 9} and 10{sup 10} cm{sup -3}. Modeling of the decrease in concentration of each cation relative to the non-recombining noble gas cation yields the rate constant for DR. The technique is applied to several species (O{sub 2}{sup +}, CO{sub 2}{sup +}, CF{sub 3}{sup +}, N{sub 2}O{sup +}) with previously determined 300 K values, showing excellent agreement. The measurements of those species are extended to 500 K, with good agreement to literature values where they exist. Measurements are also made for a range of C{sub n}H{sub m}{sup +} (C{sub 7}H{sub 7}{sup +}, C{sub 7}H{sub 8}{sup +}, C{sub 5}H{sub 6}{sup +}, C{sub 4}H{sub 4}{sup +}, C{sub 6}H{sub 5}{sup +}, C{sub 3}H{sub 3}{sup +}, and C{sub 6}H{sub 6}{sup +}) derived from benzene and toluene neutral precursors. C{sub n}H{sub m}{sup +} DR rate constants vary from 8-12 Multiplication-Sign 10{sup -7} cm{sup 3} s{sup -1} at 300 K with temperature dependences of approximately T{sup -0.7}. Where prior measurements exist these results are in agreement, with the exception of C{sub 3}H{sub 3}{sup +} where the present results disagree with a previously reported flat temperature dependence.

  5. Process for the preparation of cumene

    DOE Patents [OSTI]

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1991-10-08

    Cumene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50 C to 500 C, using as the catalyst a molecular sieve characterized as acidic by feeding propylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with propylene, thereby reacting substantially all of the propylene and recovering benzene as the principal overhead and cumene and diisopropyl benzene in the bottoms. The bottoms are fractionated, the cumene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diisopropyl benzene to cumene which is again separated and recovered. 2 figures.

  6. Process for the preparation of cumene

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1991-01-01

    Cumene is produced in a catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 50.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic by feeding propylene to the catalyst bed while benzene is conveniently added through the reflux to result in a molar excess present in the reactor to that required to react with propylene, thereby reacting substantially all of the propylene and recovering benzene as the principal overhead and cumene and diisopropyl benzene in the bottoms. The bottoms are fractionated, the cumene recovered and the bottoms are contacted with benzene in the liquid phase in a fixed bed straight pass reactor under conditions to transalkylate the benzene thereby converting most of the diisopropyl benzene to cumene which is again separated and recovered.

  7. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect (OSTI)

    Ramanathan Sampath

    2005-03-31

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period October 01, 2004 to March 31, 2005 which covers the fifth six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. During this reporting period, electrical conductivity measurements for bottom, and top phases, as well as bottom/top, and top/bottom conjugate pair phases of the ethylbenzene/water/ethanol system were performed for various ethanol volume percentage of the mixtures starting from 2% to 60%. Preliminary findings are that electrical conductivity of the bottom phase decreased as ethanol volume fraction of the mixture increased. Conductivity of the top phase was small and remained almost the same for variations in ethanol volume fraction of the mixture. Conductivity of the emulsion of the conjugate pair phases decreased as the fraction of volume of the top phase was increased and vice versa. Also inversion phenomena was observed. Detailed analyses are in progress including the prediction of conductivity data using the theoretical model already developed in this project.

  8. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect (OSTI)

    Ramanathan Sampath

    2005-09-30

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period April 01, 2005 to September 30, 2005 which covers the sixth six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. In the last reporting period, electrical conductivity measurements for bottom/top, and top/bottom conjugate pair phases of the ethylbenzene/water/ethanol system were performed for various ethanol volume percentage in the mixture: 2,10,20,33,43,50, and 56. During this reporting period, prediction of electrical conductivity data obtained in the past was conducted employing a theoretical model already developed in this project. Results of the comparisons for 2, and 10% ethanol volume in the mixture are presented here. A good agreement was obtained between the predicted emulsion conductivities and the measured values. To date about 99% of the proposed work has been completed. Conductivity prediction for 56% ethanol volume in the mixture is in progress. Following this prediction, a final report will be developed describing the research activities conducted through the entire project period including results and conclusions.

  9. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... USE YMP Yucca Mountain Site Characterization Office, Las Vegas, NV (United ... health effects (carbonyl, PAH, NPAH, benzene) as well as PM particle count and size distribution. ...

  10. Assessment of Standard Force Field Models against High-Quality ab initio Potential Curves for Prototypes of pi-pi, CH/pi, and SH/pi Interactions

    SciTech Connect (OSTI)

    Sumpter, Bobby G; Sherrill, David; Sinnokrot, Mutasem O; Marshall, Michael S.; Hohenstein, Edward G.; Walker, Ross; Gould, Ian R

    2009-01-01

    Several popular force fields, namely, CHARMM, AMBER, OPLS-AA, and MM3, have been tested for their ability to reproduce highly accurate quantum mechani- cal potential energy curves for noncovalent interactions in the benzene dimer, the benzene-CH4 complex, and the benzene-H2S complex. All of the force fields are semi-quantitatively correct, but none of them is consistently reliable quantitatively. Re-optimization of Lennard-Jones parameters and symmetry-adapted perturbation theory analysis for the benzene dimer suggests that better agreement cannot be expected unless more flexible functional forms (particularly for the electrostatic contributions)are employed for the empirical force fields.

  11. Composite Materials for Hazard Mitigation of Reactive Metal Hydrides.

    SciTech Connect (OSTI)

    Pratt, Joseph William; Cordaro, Joseph Gabriel; Sartor, George B.; Dedrick, Daniel E.; Reeder, Craig L.

    2012-02-01

    In an attempt to mitigate the hazards associated with storing large quantities of reactive metal hydrides, polymer composite materials were synthesized and tested under simulated usage and accident conditions. The composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride. Composites with vinyl-containing siloxane oligomers were also polymerized with and without added styrene and divinyl benzene. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride reduced the inherent hydrogen storage capacity of the material. The composites were found to be initially effective at reducing the amount of heat released during oxidation. However, upon cycling the composites, the mitigating behavior was lost. While the polymer composites we investigated have mitigating potential and are physically robust, they undergo a chemical change upon cycling that makes them subsequently ineffective at mitigating heat release upon oxidation of the metal hydride. Acknowledgements The authors would like to thank the following people who participated in this project: Ned Stetson (U.S. Department of Energy) for sponsorship and support of the project. Ken Stewart (Sandia) for building the flow-through calorimeter and cycling test stations. Isidro Ruvalcaba, Jr. (Sandia) for qualitative experiments on the interaction of sodium alanate with water. Terry Johnson (Sandia) for sharing his expertise and knowledge of metal hydrides, and sodium alanate in particular. Marcina Moreno (Sandia) for programmatic assistance. John Khalil (United Technologies Research Corp) for insight into the hazards of reactive metal hydrides and real-world accident scenario experiments. Summary In an attempt to mitigate and/or manage hazards associated with storing bulk quantities of reactive metal hydrides, polymer composite materials (a mixture of a mitigating polymer and a metal hydride) were synthesized and tested under simulated usage and accident conditions. Mitigating the hazards associated with reactive metal hydrides during an accident while finding a way to keep the original capability of the active material intact during normal use has been the focus of this work. These composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride, in this case a prepared sodium alanate (chosen as a representative reactive metal hydride). It was found that the polymerization of styrene and divinyl benzene could be initiated using AIBN in toluene at 70 degC. The resulting composite materials can be either hard or brittle solids depending on the cross-linking density. Thermal decomposition of these styrene-based composite materials is lower than neat polystyrene indicating that the chemical nature of the polymer is affected by the formation of the composite. The char-forming nature of cross-linked polystyrene is low and therefore, not an ideal polymer for hazard mitigation. To obtain composite materials containing a polymer with higher char-forming potential, siloxane-based monomers were investigated. Four vinyl-containing siloxane oligomers were polymerized with and without added styrene and divinyl benzene. Like the styrene materials, these composite materials exhibited thermal decomposition behavior significantly different than the neat polymers. Specifically, the thermal decomposition temperature was shifted approximately 100 degC lower than the neat polymer signifying a major chemical change to the polymer network. Thermal analysis of the cycled samples was performed on the siloxane-based composite materials. It was found that after 30 cycles the siloxane-containing polymer composite material has similar TGA/DSC-MS traces as the virgin composite material indicating that the polymer is physically intact upon cycling. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride in the form of a composite material reduced the inherent hydrogen storage capacity of the material. This reduction in capacity was observed to be independent of the amount of charge/discharge cycles except for the composites containing siloxane, which showed less of an impact on hydrogen storage capacity as it was cycled further. While the reason for this is not clear, it may be due to a chemically stabilizing effect of the siloxane on the metal hydride. Flow-through calorimetry was used to characterize the mitigating effectiveness of the different composites relative to the neat (no polymer) material. The composites were found to be initially effective at reducing the amount of heat released during oxidation, and the best performing material was the siloxane-containing composite which reduced the heat release to less than 50% of the value of the neat material. However, upon cycling the composites, all mitigating behavior was lost. The combined results of the flow-through calorimetry, hydrogen capacity, and thermogravimetric analysis tests lead to the proposed conclusion that while the polymer composites have mitigating potential and are physically robust under cycling, they undergo a chemical change upon cycling that makes them ineffective at mitigating heat release upon oxidation of the metal hydride.

  12. Method of making fine-grained triaminotrinitrobenzene

    DOE Patents [OSTI]

    Benziger, T.M.

    1983-07-26

    A method is given for forming a fine-grained species of the insensitive high explosive sym-triaminotrinitrobenzene (TATB) without grinding. In accordance with the method, 1,3,5-trichloro-2,4,6-trinitrobenzene (TCTNB) is aminated by reaction with gaseous ammonia in an emulsion of toluene in water. The ratio of water to toluene in the emulsion is selected so that toluene is the dispersed phase in the emulsion. The size of the dispersed TCTNB-containing toluene droplets determines the particle size of the resulting TATB. The emulsion is preferably formed with an emulsifier such as ammonium oleate, which may be generated in situ from oleic acid, and stabilized with a protective colloid such as polyvinyl alcohol.

  13. Method of making fine-grained triaminotrinitrobenzene

    DOE Patents [OSTI]

    Benziger, Theodore M.

    1984-01-01

    A method of forming a fine-grained species of the insensitive high explosive sym-triaminotrinitrobenzene (TATB) without grinding. In accordance with the method, 1,3,5-trichloro-2,4,6-trinitrobenzene (TCTNB) is aminated by reaction with gaseous ammonia in an emulsion of toluene in water. The ratio of water to toluene in the emulsion is selected so that toluene is the dispersed phase in the emulsion. The size of the dispersed TCTNB-containing toluene droplets determines the particle size of the resulting TATB. The emulsion is preferably formed with an emulsifier such as ammonium oleate, which may be generated in situ from oleic acid, and stabilized with a protective colloid such as polyvinyl alcohol.

  14. Molecular catalytic coal liquid conversion. Quarterly status...

    Office of Scientific and Technical Information (OSTI)

    The relationship between the turnover number of the catalyst and the reaction time was obtained. Other aromatic compounds such as toluene, n-butylbenzene, tetralin, o-xylene all ...

  15. Control of Substrate Access to the Active Site and Catalytic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Control of Substrate Access to the Active Site and Catalytic Mechanism of Methane and Toluene Monooxygenases Friday, June 22, 2012 - 3:30pm SSRL Main Conference Room 137-322 Prof....

  16. Center for Nanophase Materials Sciences (CNMS) - CNMS User Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    polymers is in a partially collapsed state in D2O, whereas it expands in toluene and methanol. SANS data also suggest that the individual polymers assume the shape of a rigid...

  17. Hydrocarbon Effect on a Fe-zeolite Urea-SCR Catalyst: An Experimental and Modeling Study

    SciTech Connect (OSTI)

    Devarakonda, Maruthi N.; Tonkyn, Russell G.; Herling, Darrell R.

    2010-04-14

    Synergies between various catalytic converters such as SCR and DPF are vital to the success of an integrated aftertreatment system for simultaneous NOx and particulate matter control in diesel engines. Several issues such as hydrocarbon poisoning, thermal aging and other coupled aftertreatment dynamics need to be addressed to develop an effective emission control system. This paper reports an experimental and modeling study to understand the effect of hydrocarbons on a Fe-zeolite urea-SCR bench reactor. Several bench-reactor tests to understand the inhibition of NOx oxidation, to characterize hydrocarbon storage and to investigate the impact of hydrocarbons on SCR reactions were conducted. Toluene was chosen as a representative hydrocarbon in diesel exhaust and various tests using toluene reveal its inhibition of NO oxidation at low temperatures and its oxidation to CO and CO2 at high temperatures. Surface isotherm tests were conducted to characterize the adsorption-desorption equilibrium of toluene through Langmuir isotherms. Using the rate parameters, a toluene storage model was developed and validated in simulation. With toluene in the stream, controlled SCR tests were run on the reactor and performance metrics such as NOx conversion and NH3 slip were compared to a set of previously run tests with no toluene in the stream. Tests indicate a significant effect of toluene on NOx and NH3 conversion efficiencies even at temperatures greater than 300oC. A kinetic model to address the toluene inhibition during NO oxidation reaction was developed and is reported in the paper. This work is significant especially in an integrated DPF-SCR aftertreatment scenario where the SCR catalyst on the filter substrate is exposed to un-burnt diesel hydrocarbons during active regeneration of the particulate filter.

  18. The use Na, Li, K cations for modification of ZSM-5 zewolite to control hydrocarbon cold-start emission

    SciTech Connect (OSTI)

    Golubeva V.; Rohatgi U.; Korableva, A.; Anischenko, O.; Kustov, L.; Nissenbaum, V; Viola, M.B.

    2012-08-29

    This paper addresses the problem of controlling hydrocarbon emissions from cold-start of engines by investigating the adsorbents which could adsorb the hydrocarbons at cold temperatures and hold them to 250-300 ?. The materials, that has been studied, are based on the modification of ZSM-5 (SiO{sub 2}/Al{sub 2}O{sub 3} = 35) zeolite with Li, K, Na cations. It has been shown that the introduction of Li, Na and K in an amount that is equivalent to the content of Al in zeolite results in occurrence of toluene temperature desorption peaks at high-temperatures. The toluene temperature desorption curves for 5%Li-ZSM-5 and 2.3%Na-ZSM-5 zeolites are identical and have peak toluene desorption rate between 200 to 400 ?. Upon analysis of toluene adsorption isotherms for 2.3%Na-ZSM-5 and 5%Li-ZSM-5, it was concluded that the toluene diffusion inside of the modified zeolites channels is extremely slow and the sorption capacity of 2.3%Na-ZSM-5 is higher than with 5%Li-ZSM-5. The 2.3%Na-ZSM-5 didn't change toluene temperature programmed desorption (TPD) rate of curve after the treatment in environment with 10% ?{sub 2}? at 750-800 ? for about 28 h. The 2.3%Na-ZSM-5 zeolite is very promising as adsorbent to control the cold-start hydrocarbon emissions.

  19. FY12 ARRA-NRAP Report – Studies to Support Risk Assessment of Geologic Carbon Sequestration

    SciTech Connect (OSTI)

    Cantrell, Kirk J.; Shao, Hongbo; Thompson, C. J.; Zhong, Lirong; Jung, Hun Bok; Um, Wooyong

    2011-09-27

    This report summarizes results of research conducted during FY2012 to support the assessment of environmental risks associated with geologic carbon dioxide (CO2) sequestration and storage. Several research focus areas are ongoing as part of this project. This includes the quantification of the leachability of metals and organic compounds from representative CO2 storage reservoir and caprock materials, the fate of metals and organic compounds after release, and the development of a method to measure pH in situ under supercritical CO2 (scCO2) conditions. Metal leachability experiments were completed on 6 different rock samples in brine in equilibrium with scCO2 at representative geologic reservoir conditions. In general, the leaching of RCRA metals and other metals of concern was found to be limited and not likely to be a significant issue (at least, for the rocks tested). Metals leaching experiments were also completed on 1 rock sample with scCO2 containing oxygen at concentrations of 0, 1, 5, and 10% to simulate injection of CO2 originating from the oxy-fuel combustion process. Significant differences in the leaching behavior of certain metals were observed when oxygen is present in the CO2. These differences resulted from oxidation of sulfides, release of sulfate, ferric iron and other metals, and subsequent precipitation of iron oxides and some sulfates such as barite. Experiments to evaluate the potential for mobilization of organic compounds from representative reservoir materials and cap rock and their fate in porous media (quartz sand) have been conducted. Results with Fruitland coal and Gothic shale indicate that lighter organic compounds were more susceptible to mobilization by scCO2 compared to heavier compounds. Alkanes demonstrated very low extractability by scCO2. No significant differences were observed between the extractability of organic compounds by dry or water saturated scCO2. Reaction equilibrium appears to have been reached by 96 hours. When the scCO2 was released from the reactor, less than 60% of the injected lighter compounds (benzene, toluene) were transported through dry sand column by the CO2, while more than 90% of the heavier organics were trapped in the sand column. For wet sand columns, most (80% to 100%) of the organic compounds injected into the sand column passed through, except for naphthalene which was substantial removed from the CO2 within the column. A spectrophotometric method was developed to measure pH in brines in contact with scCO2. This method provides an alternative to fragile glass pH electrodes and thermodynamic modeling approaches for estimating pH. The method was tested in simulated reservoir fluids (CO2–NaCl–H2O) at different temperatures, pressures, and ionic strength, and the results were compared with other experimental studies and geochemical models. Measured pH values were generally in agreement with the models, but inconsistencies were present between some of the models.

  20. An Innovative System for the Efficient and Effective Treatment of Non-Traditional Waters for Reuse in Thermoelectric Power Generation

    SciTech Connect (OSTI)

    John Rodgers; James Castle

    2008-08-31

    This study assessed opportunities for improving water quality associated with coal-fired power generation including the use of non-traditional waters for cooling, innovative technology for recovering and reusing water within power plants, novel approaches for the removal of trace inorganic compounds from ash pond effluents, and novel approaches for removing biocides from cooling tower blowdown. This research evaluated specifically designed pilot-scale constructed wetland systems for treatment of targeted constituents in non-traditional waters for reuse in thermoelectric power generation and other purposes. The overall objective of this project was to decrease targeted constituents in non-traditional waters to achieve reuse criteria or discharge limitations established by the National Pollutant Discharge Elimination System (NPDES) and Clean Water Act (CWA). The six original project objectives were completed, and results are presented in this final technical report. These objectives included identification of targeted constituents for treatment in four non-traditional water sources, determination of reuse or discharge criteria for treatment, design of constructed wetland treatment systems for these non-traditional waters, and measurement of treatment of targeted constituents in non-traditional waters, as well as determination of the suitability of the treated non-traditional waters for reuse or discharge to receiving aquatic systems. The four non-traditional waters used to accomplish these objectives were ash basin water, cooling water, flue gas desulfurization (FGD) water, and produced water. The contaminants of concern identified in ash basin waters were arsenic, chromium, copper, mercury, selenium, and zinc. Contaminants of concern in cooling waters included free oxidants (chlorine, bromine, and peroxides), copper, lead, zinc, pH, and total dissolved solids. FGD waters contained contaminants of concern including arsenic, boron, chlorides, selenium, mercury, chemical oxygen demand (COD), and zinc. Similar to FGD waters, produced waters contained contaminants of concern that are predominantly inorganic (arsenic, cadmium, chlorides, chromium, copper, lead, mercury, nickel, sulfide, zinc, total dissolved solids), but also contained some organics (benzene, PAHs, toluene, total organic carbon, total suspended solids, and oil and grease). Constituents of concern that may cause chemical scaling, biofouling and corrosion, such as pH, hardness and ionic strength, and nutrients (P, K, and N) may also be found in all four non-traditional waters. NPDES permits were obtained for these non-traditional waters and these permit limits are summarized in tabular format within this report. These limits were used to establish treatment goals for this research along with toxicity values for Ceriodaphnia dubia, water quality criteria established by the US EPA, irrigation standards established by the United States Department of Agriculture (USDA), and reuse standards focused on minimization of damage to the power plant by treated waters. Constructed wetland treatment systems were designed for each non-traditional water source based on published literature reviews regarding remediation of the constituents of concern, biogeochemistry of the specific contaminants, and previous research. During this study, 4 non-traditional waters, which included ash basin water, cooling water, FGD water and produced water (PW) were obtained or simulated to measure constructed wetland treatment system performance. Based on data collected from FGD experiments, pilot-scale constructed wetland treatment systems can decrease aqueous concentrations of elements of concern (As, B, Hg, N, and Se). Percent removal was specific for each element, including ranges of 40.1% to 77.7% for As, 77.6% to 97.8% for Hg, 43.9% to 88.8% for N, and no measureable removal to 84.6% for Se. Other constituents of interest in final outflow samples should have aqueous characteristics sufficient for discharge, with the exception of chlorides (<2000 mg/L). Based on total dissolved solids, co-

  1. Use of Advanced Oxidation and Aerobic Degradation for Remediation of Various Hydrocarbon Contaminates

    SciTech Connect (OSTI)

    Paul Fallgren

    2009-03-06

    Western Research Institute in conjunction with Sierra West Consultants, Inc., Tetra Tech, Inc., and the U.S. Department of Energy conducted laboratory and field studies to test different approaches to enhance degradation of hydrocarbons and associated contaminants. WRI in conjunction with Sierra West Consultants, Inc., conducted a laboratory and field study for using ozone to treat a site contaminated with MTBE and other hydrocarbons. Results from this study demonstrate that a TOD test can be used to resolve the O{sub 3} dosage problem by establishing a site-specific benchmark dosage for field ozone applications. The follow-up testing of the laboratory samples provided indications that intrinsic biodegradation could be stimulated by adding oxygen. Laboratory studies also suggests that O3 dosage in the full-scale field implementation could be dialed lower than stoichiometrically designed to eliminate the formation of Cr(VI). WRI conducted a study involving a series of different ISCO oxidant applications to diesel-contaminated soil and determined the effects on enhancing biodegradation to degrade the residual hydrocarbons. Soils treated with permanganate followed by nutrients and with persulfate followed by nutrients resulted in the largest decrease in TPH. The possible intermediates and conditions formed from NOM and TPH oxidation by permanganate and activated persulfate favors microbial TPH degrading activity. A 'passive-oxidation' method using microbial fuel cell (MFC) technology was conducted by WRI in conjunction with Tetra Tech, Inc., to degrade MTBE in groundwater. These experiments have demonstrated that a working MFC (i.e., one generating power) could be established in the laboratory using contaminated site water or buffered media inoculated with site water and spiked with MTBE, benzene, or toluene. Electrochemical methods were studied by WRI with goal of utilizing low voltage and amperage electrical sources for 'geo-oxidation' of organic contaminants. The results from a study with TCE contaminated-clay indicate that electrochemically inducing reductive dechlorination of TCE in a saturated matrix may offer an effective and viable alternative to remediation TCE and other contaminants with potential of being reduced. Another study focused on steel wool oxidation to electrochemically increase population of hydrocarbon-degrading denitrifying bacteria. Significantly larger denitrifying activity was observed in the cathode chamber of a treatment unit setup like an MFC with steel wool as the anode. This enhanced nitrate reduction could be due to direct electron utilization by denitrifying bacteria on the cathode, thereby stimulating microbial denitrification or a combination of electron transfer directly to NO{sub 3}{sup -} and electron transfer to nitrate reducing bacteria, which may serve as a type of bio-catalyst on the cathode for nitrate reduction. Overall, the studies conducted under Task 72 demonstrated different innovative methods to enhance petroleum hydrocarbon degradation and associated contaminants.

  2. Numerical study of the effect of oxygenated blending compounds on soot formation in shock tubes

    SciTech Connect (OSTI)

    Boehm, H.; Braun-Unkhoff, M.

    2008-04-15

    This numerical study deals with the influence of blends on the amount of soot formed in shock tubes, which were simulated by assuming a homogeneous plug flow reactor model. For this purpose, first, the reaction model used here was validated against experimental results previously obtained in the literature. Then, the soot volume fractions of various mixtures of methyl tert-butyl ether (MTBE)-benzene, isobutene-benzene, methanol-benzene, and ethanol-benzene diluted in argon were simulated and compared to the results of benzene-argon pyrolysis at 1721 K and 5.4 MPa. For MTBE, isobutene, methanol, and ethanol, small amounts of additives to benzene-argon mixtures promoted soot formation, for the shock tube model assumed, while higher concentrations of these additives led to smaller soot volume fractions in comparison to pure benzene-argon pyrolysis. The most significant soot promotion effect was found for the additives MTBE and isobutene. The channel for MTBE decomposition producing isobutene and methanol is very effective at temperatures beyond 1200 K. Thus, both MTBE-benzene and isobutene-benzene mixtures diluted in argon showed rather similar behavior in regard to soot formation. Special emphasis was directed toward the causes for the concentration-dependent influence of the blends on the amount of soot formed. Aromatic hydrocarbons and acetylene were identified as key gas-phase species that determine the trends in the formation of soot of various mixtures. From reaction flux analysis for phenanthrene, it was deduced that the combinative routes including phenyl species play a major role in forming PAHs, especially at early reaction times. It is found that the additives play an important role in providing material to grow side chains, such as by reaction channels including phenylacetylene or benzyl, which are confirmed to form aromatic hydrocarbons and thus to influence the amount of soot formed, particularly when the concentrations of the blends are increased. (author)

  3. Mobile Source Air Toxics Rule (released in AEO2008)

    Reports and Publications (EIA)

    2008-01-01

    On February 9, 2007, the Environmental Protection Agency (EPA) released its MSAT2 rule, which will establish controls on gasoline, passenger vehicles, and portable fuel containers. The controls are designed to reduce emissions of benzene and other hazardous air pollutants. Benzene is a known carcinogen, and the EPA estimates that mobile sources produced more than 70% of all benzene emissions in 1999. Other mobile source air toxics, including 1,3-butadiene, formaldehyde, acetaldehyde, acrolein, and naphthalene, also are thought to increase cancer rates or contribute to other serious health problems.

  4. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, L.A. Jr.

    1989-07-18

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

  5. December 2015 Most Viewed Documents for Physics | OSTI, US Dept...

    Office of Scientific and Technical Information (OSTI)

    equation of state of liquid nitrogen, oxygen, benzene, and 1-butene shocked to 60 GPa Hamilton, D.C. (1986) 48 Direct Fast-Neutron Detection DC Stromswold; AJ Peurrung; RR Hansen; ...

  6. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1994-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  7. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1993-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  8. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A.

    1989-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  9. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1993-09-07

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene to about the mid point of the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 figures.

  10. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1994-06-14

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a molecular sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

  11. Assessment of heavy oil conversion

    SciTech Connect (OSTI)

    Gleim, W.T.K.

    1983-08-01

    Removal of benzene insoluble asphaltene components greatly facilitates and improves the subsequent upgrading of residual oils, the desulfurization in particular. For the upgrading of Venezualean oils, the Aurobon process is still the only feasible solution.

  12. DIRECT DISPOSAL OF A RADIOACTIVE ORGANIC WASTE IN A CEMENTITIOUS WASTE FORM

    SciTech Connect (OSTI)

    Zamecnik, J; Alex Cozzi, A; Russell Eibling, R; Jonathan Duffey, J; Kim Crapse, K

    2007-02-22

    The disposition of {sup 137}Cs-containing tetraphenylborate (TPB) waste at the Savannah River Site (SRS) by immobilization in the cementitious waste form, or grout called ''saltstone'' was proposed as a straightforward, cost-effective method for disposal. Tests were performed to determine benzene release due to TPB decomposition in saltstone at several initial TPB concentrations and temperatures. The benzene release rates for simulants and radioactive samples were generally comparable at the same conditions. Saltstone monoliths with only the top surface exposed to air at 25 and 55 C at any tetraphenylborate concentration or at any temperature with 30 mg/L TPB gave insignificant releases of benzene. At higher TPB concentrations and 75 and 95 C, the benzene release could result in exceeding the Lower Flammable Limit in the saltstone vaults.

  13. Catalytic reactive separation system for energy-efficient production of cumene

    DOE Patents [OSTI]

    Buelna, Genoveva; Nenoff, Tina M.

    2009-07-28

    The present invention relates to an atmospheric pressure, reactive separation column packed with a solid acid zeolite catalyst for producing cumene from the reaction of benzene with propylene. Use of this un-pressurized column, where simultaneous reaction and partial separation occur during cumene production, allow separation of un-reacted, excess benzene from other products as they form. This high-yielding, energy-efficient system allows for one-step processing of cumene, with reduced need for product purification. Reacting propylene and benzene in the presence of beta zeolite catalysts generated a selectivity greater than 85% for catalytic separation reactions at a reaction temperature of 115 degrees C and at ambient pressure. Simultaneously, up to 76% of un-reacted benzene was separated from the product; which could be recycled back to the reactor for re-use.

  14. The Reaction of bis(1,2,4-tri-t-butylcyclopentadienyl)ceriumbenzyl...

    Office of Scientific and Technical Information (OSTI)

    involves a haptotropic shift of the Cp2Ce fragment so that at the transition state the para-carbon of the benzene ring is attached to the Cp2Ce fragment while the CH2 fragment of ...

  15. APPLICATIONS OF CFD METHOD TO GAS MIXING ANALYSIS IN A LARGE-SCALED TANK

    SciTech Connect (OSTI)

    Lee, S; Richard Dimenna, R

    2007-03-19

    The computational fluid dynamics (CFD) modeling technique was applied to the estimation of maximum benzene concentration for the vapor space inside a large-scaled and high-level radioactive waste tank at Savannah River site (SRS). The objective of the work was to perform the calculations for the benzene mixing behavior in the vapor space of Tank 48 and its impact on the local concentration of benzene. The calculations were used to evaluate the degree to which purge air mixes with benzene evolving from the liquid surface and its ability to prevent an unacceptable concentration of benzene from forming. The analysis was focused on changing the tank operating conditions to establish internal recirculation and changing the benzene evolution rate from the liquid surface. The model used a three-dimensional momentum coupled with multi-species transport. The calculations included potential operating conditions for air inlet and exhaust flows, recirculation flow rate, and benzene evolution rate with prototypic tank geometry. The flow conditions are assumed to be fully turbulent since Reynolds numbers for typical operating conditions are in the range of 20,000 to 70,000 based on the inlet conditions of the air purge system. A standard two-equation turbulence model was used. The modeling results for the typical gas mixing problems available in the literature were compared and verified through comparisons with the test results. The benchmarking results showed that the predictions are in good agreement with the analytical solutions and literature data. Additional sensitivity calculations included a reduced benzene evolution rate, reduced air inlet and exhaust flow, and forced internal recirculation. The modeling results showed that the vapor space was fairly well mixed and that benzene concentrations were relatively low when forced recirculation and 72 cfm ventilation air through the tank boundary were imposed. For the same 72 cfm air inlet flow but without forced recirculation, the heavier benzene gas was stratified. The results demonstrated that benzene concentrations were relatively low for typical operating configurations and conditions. Detailed results and the cases considered in the calculations will be discussed here.

  16. Metal-doped organic gels and method thereof

    DOE Patents [OSTI]

    Satcher, Jr., Joe H.; Baumann, Theodore F.

    2003-09-02

    Disclosed herein is a sol-gel polymerization process for synthesizing metal-doped organic gels. The process polymerizes metal salts of hydroxylated benzenes or hydroxylated benzene derivatives with alkyl or aryl aldehydes to form metal-doped, wet, organic gels. The gels can then be dried by supercritical solvent extraction to form metal-doped aerogels or by evaporation to form metal-doped xerogels. The aerogels and xerogels can then be pyrolyzed.

  17. Metal-doped organic gels and method thereof

    DOE Patents [OSTI]

    Satcher, Jr., Joe H.; Baumann, Theodore F.

    2007-10-23

    Disclosed herein is a sol-gel polymerization process for synthesizing metal-doped organic gels. The process polymerizes metal salts of hydroxylated benzenes or hydroxylated benzene derivatives with alkyl or aryl aldehydes to form metal-doped, wet, organic gels. The gels can then be dried by supercritical solvent extraction to form metal-doped aerogels or by evaporation to form metal-doped xerogels. The aerogels and xerogels can then be pyrolyzed.

  18. TOXICITY CHARACTERISTIC LEACHING PROCEDURE APPLIED TO RADIOACTIVE SALTSTONE CONTAINING TETRAPHENYLBORATE: DEVELOPMENT OF A MODIFIED ZERO-HEADSPACE EXTRACTOR

    SciTech Connect (OSTI)

    Crapse, K.; Cozzi, A.; Crawford, C.; Jurgensen, A.

    2006-09-30

    In order to assess the effect of extended curing times at elevated temperatures on saltstone containing Tank 48H waste, saltstone samples prepared as a part of a separate study were analyzed for benzene using a modification of the United States Environmental Protection Agency (USEPA) method 1311 Toxicity Characteristic Leaching Procedure (TCLP). To carry out TCLP for volatile organic analytes (VOA), such as benzene, in the Savannah River National Laboratory (SRNL) shielded cells (SC), a modified TCLP Zero-Headspace Extractor (ZHE) was developed. The modified method was demonstrated to be acceptable in a side by side comparison with an EPA recommended ZHE using nonradioactive saltstone containing tetraphenylborate (TPB). TCLP results for all saltstone samples tested containing TPB (both simulant and actual Tank 48H waste) were below the regulatory limit for benzene (0.5 mg/L). In general, higher curing temperatures corresponded to higher concentrations of benzene in TCLP extract. The TCLP performed on the simulant samples cured under the most extreme conditions (3000 mg/L TPB in salt and cured at 95 C for at least 144 days) resulted in benzene values that were greater than half the regulatory limit. Taking into account that benzene in TCLP extract was measured on the same order of magnitude as the regulatory limit, that these experimental conditions may not be representative of actual curing profiles found in the saltstone vault and that there is significant uncertainty associated with the precision of the method, it is recommended that to increase confidence in TCLP results for benzene, the maximum curing temperature of saltstone be less than 95 C. At this time, no further benzene TCLP testing is warranted. Additional verification would be recommended, however, should future processing strategies result in significant changes to salt waste composition in saltstone as factors beyond the scope of this limited study may influence the decomposition of TPB in saltstone.

  19. INVESTIGATION OF PHASE AND EMULSION BEHAVIOR, SURFACTANT RETENTION, AND CONDENSATE RECOVERY FOR CONDENSATE/WATER/ETHANOL MIXTURES

    SciTech Connect (OSTI)

    Ramanathan Sampath

    2003-10-01

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period April 01, 2003 to September 30, 2003 which covers the second six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. During this reporting period, salinity scans were completed for 0, 5, 10, 20, 50, 100, 250, 500, and 1000 mM salt concentrations at room temperature to identify optimal salinity intervals in which all three phases coexist for this system. Temperature scans are in progress at Morehouse College to identify the optimal temperature, and the temperature intervals in which all three phases coexist for this system. Coreflooding experiments are being conducted by our industrial partner in this project, Surtek, CO, to measure the effectiveness for surfactant retention and condensate recovery in flooding processes. Review of the current literature in the subject area, and modeling efforts that were established in our previous studies to predict electrical conductivities and inversion phenomena was continued from the previous reporting period. Based on the review a computer model to predict electrical conductivities of the ethylbenzene (that has the equivalent carbon number of the condensate)/water/ethanol system is being developed.

  20. Detection of volatile organic compounds using surface enhanced Raman scattering

    SciTech Connect (OSTI)

    Chang, A S; Maiti, A; Ileri, N; Bora, M; Larson, C C; Britten, J A; Bond, T C

    2012-03-22

    The authors present the detection of volatile organic compounds directly in their vapor phase by surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. The type of nanopillars is known as the tapered pillars. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of toluene vapor. The results show that SERS signal from a toluene vapor concentration of ppm level can be achieved, and the toluene vapor can be detected within minutes of exposing the SERS substrate to the vapor. A simple adsorption model is developed which gives results matching the experimental data. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors.

  1. Laboratory Investigation of Organic Aerosol Formation from Aromatic Hydrocarbons

    DOE R&D Accomplishments [OSTI]

    Molina, Luisa T.; Molina, Mario J.; Zhang, Renyi

    2006-08-23

    Our work for this DOE funded project includes: (1) measurements of the kinetics and mechanism of the gas-phase oxidation reactions of the aromatic hydrocarbons initiated by OH; (2) measurements of aerosol formation from the aromatic hydrocarbons; and (3) theoretical studies to elucidate the OH-toluene reaction mechanism using quantum-chemical and rate theories.

  2. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, L.A. Jr.; Arganbright, R.P.; Hearn, D.

    1993-01-05

    Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70 C and 500 C and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

  3. Alkylation of organic aromatic compounds

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A.; Arganbright, Robert P.; Hearn, Dennis

    1993-01-01

    Aromatic compounds are alkylated in a combination reactor/distillation column comprising a vessel suitable for operating between 70.degree. C. and 500.degree. C. and from 0.5 to 20 atmospheres pressure; an inert distillation packing in the lower one-third of said vessel; solid acidic catalytic material such as zeolites or an acidic cation exchange resin supported in the middle one-third of said vessel; and inert distillation packing in the upper one-third of said vessel. A benzene inlet is located near the upper end of the vessel; an olefin inlet is juxtaposed with said solid acidic catalytic material; a bottoms outlet is positioned near the bottom of said vessel for removing said cumene and ethyl benzene; and an overhead outlet is placed at the top of said vessel for removing any unreacted benzene and olefin.

  4. New metal-organic nanomaterials synthesized by laser irradiation of organic liquids

    SciTech Connect (OSTI)

    Kuzmin, Stanislav L.; Wesolowski, Michal J.; Duley, Walter W.

    2014-03-31

    A new type of metal-organic composition consisting of clusters of nanoparticles has been synthesised by laser irradiation of metallocene/benzene solutions. The metallocene molecules in this reaction become the source of the metal. Exposure to high-energy femtosecond laser pulses dehydrogenate benzene molecules and initiate the high-temperature high-pressure conditions that results in the synthesis of new materials. Irradiation experiments have been carried out on ferrocene/benzene and on other solutions. With ferrocene the synthesis of a new compound has been confirmed by X-ray powder diffraction as the peaks detected do not correspond to any known substance in the Crystallography Open Database. Theoretical simulation of the periodic structure of this new carbide predicts that it has hexagonal symmetry and a unit cell with a = 3.2A and c =2.8A. The exact structure is still uncertain but may be determined from scanning tunneling microscope (STM) studies.

  5. QER- Comment of Jeff Cobb 2

    Broader source: Energy.gov [DOE]

    Hello, Please also see the letter after my signature at the bottom. I was at the unitization hearing for the Helis Oil planned fracking operation in St. Tammany Parish. I refrained from speaking, because I do not live in St. Tammany. I wish to affirm my support for everything said at that hearing in opposition to the unitization permit, and everything relayed to the Army Corps of Engineers regarding the wetlands permit opposing it. As well as opposition to fracking not only in St Tammany, but anywhere in the world, for the multiple reasons I outline below. Primarily I'm opposed because the Texas Railroad Commission has conducted a study that shows conclusively that water wells located near fracking operations in the Barnett Shale have been contaminated with hyropcarbons that could ONLY have come from the Barnett Shale. Given that the Southern Hills Aquifer is the sole source aquifer for Baton Rouge as well as hundreds of thousands of other people in southeastern Louisiana including much if not all of St Tammany Parish, and the recent Legislative Auditors report showing DNR's regulation of thousands of oil and gas wells is negligent, allowing any drilling in ANY sole source aquifer is an accident waiting to happen, with repercussions lasting centuries. The World Bank is in agreement with other global experts such as PricewaterhouseCoopers that only 20% of the known fossil fuel reserves can be burned (http://blogs.worldbank.org/climatechange/carbon-bubbles-stranded-assets.) This means the remaining 80% of reserves are stranded assets, resulting in a carbon bubble in the investment market. The biggest of the Big Five global accounting firms, PricewaterhouseCoopers agrees with this in their report, 'Too Late for Two Degrees?' (http://www.pwc.co.uk/sustainability-climate-change/publications/low-carb...). ExxonMobil has recognized this carbon bubble risk, and then dismissed it (http://corporate.exxonmobil.com/en/environment/climate-change/managing-c...). Which is like an alcoholic admitting their addiction, and then saying 'but my continued drinking of alcohol is necessary'. Denial is the most seductive whore in the human psyche. All nations in the UN agreed to keep global warming driven mostly by the burning of fossil fuels below 2 degrees C in 2009. We are currently on track for 3-4 degrees C warming, perhaps higher. We have already identified fossil fuel reserves containing 2,795 gigatons of carbon (www.carbontracker.org), while we can only burn 565 gigatons of carbon to stay below the agreed upon 2 degrees C target (https://www.pik-potsdam.de/news/press-releases/archive/2009/on-the-way-t...). As we have five times more identified reserves than we can burn, the search for more is an exercise in futility. Although EPA has conducted two major studies linking well water contamination to fracking in both Pavilion, Wyoming and Dimock, Pennsylvania, this study by the Texas Railroad Commission is the most definitive to date (http://www.earthworksaction.org/media/detail/scientists_fracking_pollute...). Lower level EPA employees were told to discontinue and/or bury the results of those two studies, no doubt because higher level EPA employees were paid by the fossil fuel industry to hide the ugly truth that fossil fuels knew from the beginning. Louisiana already has some of the most polluted water in the US (http://www.nola.com/business/index.ssf/2014/06/louisiana_waterways_among...), as described in "Wasting Our Waterways: Toxic Industrial Pollution and Restoring the Promise of the Clean Water Act" (http://environmentamericacenter.org/sites/environment/files/reports/US_w...). Continued oil and gas activities, and particularly fracking which requires millions of gallons of water, and the 'produced' water that results which is too polluted and poisoned with benzenes, brine, and radioactive materials to be purified, must be stopped ASAP. The entire energy infrastructure for the planet needs to be upgraded to the supergrid and moved to renewables. Needless to say, after the Legislative Auditors Report it is clear that Louisiana can't be trusted to guard our health any better than Pennsylvania. "Pennsylvania has had more than 6,000 hydraulic fracturing wells drilled within the last six years, and zero state studies on their health impacts. In Pennsylvania, and near fracking operations across the country, people have won settlements from fossil fuel companies after being sickened. In many cases the drilling company imposes a gag order to prevent sickened people from spreading the word about what caused their illness and building the case that fracking has negative health effects." (http://thinkprogress.org/climate/2014/06/20/3451311/pennsylvania-frack-g...) Although the argument is often made that fracking is igniting an economic boom, climate change will wipe away any benefits, exaggerated as these benefits are certain to be. A new economic model shows risks from climate change are bigger than previously estimated, according to former chief economist for the World Bank, Sir Lord Nicholas Stern, who was knighted for his 2006 "Stern Review on the Economics of Climate Change." (http://www.lse.ac.uk/GranthamInstitute/news/dietz_stern_june2014/) Given the Legislative Auditors recent report on oil and gas wells, I have no faith in any part of the Louisiana government to regulate oil and gas activities of any kind, on any scale. Particularly as the Southern Hills Aquifer is the sole source aquifer for hundreds of thousands of people, including myself. Due to the carbon budget for the planet, we need to move away from fossil fuels and switch to clean renewable energy sources as soon as possible, which will help avoid some of the economic impacts mentioned above, as well as prevent even more poisoned water, air, and land due to oil and gas activities. Therefore I oppose any and all permits for any fossil fuel activities in the state of Louisiana. Jeff Cobb GreenARMY volunteer Very few people on earth ever get to say: 'I'm doing, right now, the most important thing I could possibly be doing.' If you join the fight against climate change, that's what you'll get to say. - Bill McKibben Louisiana Department of Wildlife & Fisheries Attn: Chris Davis Re: Louisiana Natural and Scenic Rivers System Permit Applications # 896 & 902 Dear Mr. Davis, I am writing to request a public hearing on the two permits shown above. Both of these are vital natural Louisiana scenic river resources. As such, both are enjoyed by many citizens in our extended community. The thought of allowing fresh water to be pulled out of these rivers in such large quantities to satisfy the needs of large corporate industrial projects that will pollute the water to such a degree that it can never be safely returned to the eco-system is abhorrent. According to Wilma Subra*, the early phases of production after fracking, the produced water flows to the surface mixed with flowback water. The produced water is disposed of in injection/disposal wells. The produced water contains toxic chemical contaminants: volatile organic compounds, such as benzene, ethyl benzene, toluene and xylene semi-volatile organic compound such as naphthalene, phenanthrene heavy metals such as arsenic, cadmium, chromium, lead sulfur containing compounds NORM Radioactive Radium 226, Radium 228 and Uranium 238 These are only the first permits of what will become literally, thousands, should you allow this activity. I ask you to mindfully consider the impact of thousands of hydrofracturing wells in our area, depleting water supplies at alarming rates. Thank you for your time and consideration in this matter. I look forward to hearing from you regarding public hearings on these permit requests. Additionally, I would like to request a full Environmental Impact Statement regarding the use of our scenic rivers for such activity. Sincerely, Jeff Cobb *Subra holds degrees in Microbiology/Chemistry from the University of Southwestern Louisiana, received the MacArthur Fellowship "Genius" Award from the MacArthur Foundation for helping ordinary citizens understand, cope with and combat environmental issues in their communities and was one of three finalist in the Environmental Category of the 2004 Volvo for Life Award, selected in 2011 as one of the 'Lifetime Remarkable Woman' and most recently won the 2011 Global Exchange, Human Rights Award for her ongoing work with the BP Oil Spill and the communities affected by it.

  6. STRUCTURE AND FUNCTION OF SUBSURFACE MICROBIAL COMMUNITIES AFFECTING RADIONUCLIDE TRANSPORT AND BIOIMMOBILIZATION

    SciTech Connect (OSTI)

    Joel E. Kostka; Lee Kerkhof; Kuk-Jeong Chin; Martin Keller; Joseph W. Stucki

    2011-06-15

    The objectives of this project were to: (1) isolate and characterize novel anaerobic prokaryotes from subsurface environments exposed to high levels of mixed contaminants (U(VI), nitrate, sulfate), (2) elucidate the diversity and distribution of metabolically active metal- and nitrate-reducing prokaryotes in subsurface sediments, and (3) determine the biotic and abiotic mechanisms linking electron transport processes (nitrate, Fe(III), and sulfate reduction) to radionuclide reduction and immobilization. Mechanisms of electron transport and U(VI) transformation were examined under near in situ conditions in sediment microcosms and in field investigations at the Oak Ridge Field Research Center (ORFRC), in Oak Ridge, Tennessee, where the subsurface is exposed to mixed contamination predominated by uranium and nitrate. A total of 20 publications (16 published or 'in press' and 4 in review), 10 invited talks, and 43 contributed seminars/ meeting presentations were completed during the past four years of the project. PI Kostka served on one proposal review panel each year for the U.S. DOE Office of Science during the four year project period. The PI leveraged funds from the state of Florida to purchase new instrumentation that aided the project. Support was also leveraged by the PI from the Joint Genome Institute in the form of two successful proposals for genome sequencing. Draft genomes are now available for two novel species isolated during our studies and 5 more genomes are in the pipeline. We effectively addressed each of the three project objectives and research highlights are provided. Task I - Isolation and characterization of novel anaerobes: (1) A wide range of pure cultures of metal-reducing bacteria, sulfate-reducing bacteria, and denitrifying bacteria (32 strains) were isolated from subsurface sediments of the Oak Ridge Field Research Center (ORFRC), where the subsurface is exposed to mixed contamination of uranium and nitrate. These isolates which are new to science all show high sequence identity to sequences retrieved from ORFRC subsurface. (2) Based on physiological and phylogenetic characterization, two new species of subsurface bacteria were described: the metal-reducer Geobacter daltonii, and the denitrifier Rhodanobacter denitrificans. (3) Strains isolated from the ORFRC show that Rhodanobacter species are well adapted to the contaminated subsurface. Strains 2APBS1 and 116-2 grow at high salt (3% NaCl), low pH (3.5) and tolerate high concentrations of nitrate (400mM) and nitrite (100mM). Strain 2APBS1 was demonstrated to grow at in situ acidic pHs down to 2.5. (4) R. denitrificans strain 2APBS1 is the first described Rhodanobacter species shown to denitrify. Nitrate is almost entirely converted to N2O, which may account for the large accumulation of N2O in the ORFRC subsurface. (5) G. daltonii, isolated from uranium- and hydrocarbon-contaminated subsurface sediments of the ORFRC, is the first organism from the subsurface clade of the genus Geobacter that is capable of growth on aromatic hydrocarbons. (6) High quality draft genome sequences and a complete eco-physiological description are completed for R. denitrificans strain 2APBS1 and G. daltonii strain FRC-32. (7) Given their demonstrated relevance to DOE remediation efforts and the availability of detailed genotypic/phenotypic characterization, Rhodanobacter denitrificans strain 2APBS1 and Geobacter daltonii strain FRC-32 represent ideal model organisms to provide a predictive understanding of subsurface microbial activity through metabolic modeling. Tasks II and III-Diversity and distribution of active anaerobes and Mechanisms linking electron transport and the fate of radionuclides: (1) Our study showed that members of genus Rhodanobacter and Geobacter are abundant and active in the uranium and nitrate contaminated subsurface. In the contaminant source zone of the Oak Ridge site, Rhodanobacter spp. are the predominant, active organisms detected (comprising 50% to 100% of rRNA detected). (2) We demonstrated for the first time that the function of microbial communities can be quantified in subsurface sediments using messenger RNA assays (molecular proxies) under in situ conditions. (3) Active Geobacteraceae were identified and phylogenetically characterized from the cDNA of messenger RNA extracted from ORFRC subsurface sediment cores. Multiple clone sequences were retrieved from G. uraniireducens, G. daltonii, and G. metallireducens. (4) Results show that Geobacter strain FRC-32 is capable of growth on benzoate, toluene and benzene as the electron donor, thereby providing evidence that this strain is physiologically distinct from other described members of the subsurface Geobacter clade. (5) Fe(III)-reducing bacteria transform structural Fe in clay minerals from their layer edges rather than from their basal surfaces.

  7. C{sub 6}H{sub 6}/Au(111): Interface dipoles, band alignment, charging energy, and van der Waals interaction

    SciTech Connect (OSTI)

    Abad, E.; Martinez, J. I.; Flores, F.; Ortega, J.; Dappe, Y. J.

    2011-01-28

    We analyze the benzene/Au(111) interface taking into account charging energy effects to properly describe the electronic structure of the interface and van der Waals interactions to obtain the adsorption energy and geometry. We also analyze the interface dipoles and discuss the barrier formation as a function of the metal work-function. We interpret our DFT calculations within the induced density of interface states (IDIS) model. Our results compare well with experimental and other theoretical results, showing that the dipole formation of these interfaces is due to the charge transfer between the metal and benzene, as described in the IDIS model.

  8. HEAVY METAL LOADED PLASTIC SCINTILLATING COMPOSITIONS

    DOE Patents [OSTI]

    Hyman, M. Jr.

    1962-06-26

    Thls lnventlon relates to a plastlc sclntlllatlon composltlon havlng lncorporated ln the base plastlc a lead compound. Thls compound forms a haze- free sclntillator. The lead compound has the general formula (R/sub 4/) x from the group consisting of hydrogen, alky, and phenyl, R4 ls selected from the group conslstlng of acrylyl and methacryiyl radlcals, and x ls a number from 0,5 to 1; however, when R/sub 1/, R/sub 2/, and R/sub 3/ are all hydrogen the x ls equal to 1. The phosphor ln the sclntlllatlng compositlon and the lead compound can be dlssolved ln a polymerlc resln selected from the group conslsting of polyvinyl toluene and copolymers of vlnyl toluene and cyclohexyl methacrylate. (AEC)

  9. Filamentous carbon catalytic deposition of coal-tar pitch fraction on corundum

    SciTech Connect (OSTI)

    Martynkova, G.S.; Supova, M.

    2007-01-15

    Our work was focused on deposition of volatile hydrocarbons of carbonaceous precursor on corundum wafer, taking advantage of a metallic catalyst incorporated in precursor. Coal tar-pitch, namely a fraction soluble in toluene, served as precursor material for deposition of filamentous material. The toluene-soluble fraction of tar-pitch originally contained metallic particles of iron and nickel. During heat treatment up to 1000{sup o}C, metallic particles accompanied the volatile hydrocarbons conducive to forming a filamentous deposit. The deposit obtained demonstrates a semicrystalline material that has an irregular filamentous structure with an average filament diameter of 30 {mu}m. The presence of catalysts after the deposition process was proved in the deposit but catalysts were not found in the residuum.

  10. Protein-style dynamical transition in a non-biological polymer and a non-aqueous solvent

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mamontov, E.; Sharma, V. K.; Borreguero, J. M.; Tyagi, M.

    2016-03-15

    Using neutron scattering and molecular dynamics simulation, techniques most often associated with protein dynamical transition studies, we have investigated the microscopic dynamics of one of the most common polymers, polystyrene, which was exposed to toluene vapor, mimicking the process of protein hydration from water vapor. Polystyrene with adsorbed toluene is an example of a solvent-solute system, which, unlike biopolymers, is anhydrous and lacks hydrogen bonding. Nevertheless, it exhibits the essential traits of the dynamical transition in biomolecules, such as a specific dependence of the microscopic dynamics of both solvent and host on the temperature and the amount of solvent adsorbed.more » Ultimately, we conclude that the protein dynamical transition is a manifestation of a universal solvent-solute dynamical relationship, which is not specific to either biomolecules as solute, or aqueous media as solvent, or even a particular type of interactions between solvent and solute.« less

  11. Aromatic-Hydroxyl Interaction of a Lignin Model Compound on SBA-15, Present at Pyrolysis Temperatures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kandziolka, III, Michael V.; Kidder, Michelle; Gill, Lance W.; Wu, Zili; Savara, Aditya Ashi

    2014-07-14

    An aromatic alpha-aryl ether compound (a benzyl phenyl ether analogue) was covalently grafted to mesoporous silica SBA-15, to create BPEa-SBA-15. The BPEa-SBA-15 was subjected to successive heating cycles up to 600 °C, with in situ monitoring by DRIFTS. It was found that the toluene moiety coordinates to SBA-15 surface silanol hydroxyl groups via an aromatic–hydroxyl interaction. This interaction is evidenced by a red-shift of the aromatic C–H stretches, as well as a red-shift and broadening of the surface hydroxyl O–H stretches, which are features characteristic of a hydrogen bond. These features remain present during heating until ~400 °C whereupon themore » ether linkage of BPEa-SBA-15 is cleaved, accompanied by loss of the toluene moiety.« less

  12. Process for reducing aromatic compounds in ethylenediamine with calcium

    DOE Patents [OSTI]

    Benkeser, R.A.; Laugal, J.A.; Rappa, A.

    1985-08-06

    Olefins are produced by containing an organic compound having at least one benzene ring with ethylenediamine and calcium metal, the calcium metal being used in large excess or alternatively in conjunction with an inert abrasive particulate substance. Substantially all of the organic compounds are converted to corresponding cyclic olefins, largely mono-olefins.

  13. December 4, 2013 | Center for Gas SeparationsRelevant to Clean Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Technologies | Blandine Jerome December 4, 2013 Previous Next List Jon Witte (Dept. of Chemistry, UC Berkeley) The CO2-benzene Complex: a Case Study for Assessing the Performances of Electronic Structure Approximations for Gas-Ligand Interactions in MOFs Joshua Howe (The Molecular Foundry, LBNL) First Principles Calculations of Small Molecule Binding in MOF-74 Variants

  14. Production of chemical feedstock by the methanolysis of wood

    DOE Patents [OSTI]

    Steinberg, Meyer; Fallon, Peter

    1984-07-31

    A process for the production of ethylene, benzene and carbon monoxide from particulated biomass such as wood by reaction with methane at a temperature of from 700.degree. C. to 1200.degree. C., at a pressure of from 20 psi to 100 psi for a period of from 0.2 to 10 seconds.

  15. Production of chemical feedstock by the methanolysis of wood

    DOE Patents [OSTI]

    Steinberg, M.; Fallon, P.

    1983-06-01

    A process is discussed for the production of ethylene, benzene and carbon monoxide from particulated biomass such as wood by reaction with methane at a temperature of from 700/sup 0/C to 1200/sup 0/C, at a pressure of from 20 psi to 100 psi for a period of from 0.2 to 10 seconds.

  16. Colloidal polyaniline

    DOE Patents [OSTI]

    Armes, Steven P.; Aldissi, Mahmoud

    1990-01-01

    Processable electrically conductive latex polymer compositions including colloidal particles of an oxidized, polymerized amino-substituted aromatic monomer, a stabilizing effective amount of a random copolymer containing amino-benzene type moieties as side chain constituents, and dopant anions, and a method of preparing such polymer compositions are provided.

  17. Modified resins for solid-phase extraction

    DOE Patents [OSTI]

    Fritz, James S.; Sun, Jeffrey J.

    1991-12-10

    A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

  18. Process for reducing aromatic compounds in ethylenediamine with calcium

    DOE Patents [OSTI]

    Benkeser, Robert A.; Laugal, James A.; Rappa, Angela

    1985-01-01

    Olefins are produced by containing an organic compound having at least one benzene ring with ethylenediamine and calcium metal, the calcium metal being used in large excess or alternatively in conjunction with an inert abrasive particulate substance. Substantially all of the organic compounds are converted to corresponding cyclic olefins, largely mono-olefins.

  19. REMOVAL OF CHLORIDE FROM AQUEOUS SOLUTIONS

    DOE Patents [OSTI]

    Schulz, W.W.

    1959-08-01

    The removal of chlorides from aqueons solutions is described. The process involves contacting the aqueous chloride containing solution with a benzene solution about 0.005 M in phenyl mercuric acetate whereby the chloride anions are taken up by the organic phase and separating the organic phase from the aqueous solutions.

  20. Modified resins for solid-phase extraction

    DOE Patents [OSTI]

    Fritz, James S.; Sun, Jeffrey J.

    1993-07-27

    A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.

  1. Oxidation of anthracene and benzo[a]pyrene by laccases from Trametes versicolor

    SciTech Connect (OSTI)

    Collins, P.J.; Dobson, A.D.W.; Kotterman, M.J.J.; Field, J.A.

    1996-12-01

    Polycyclic aromatic hydrocarbons, particularly benzene homologs, are highly toxic organic pollutants. One of the three major groups of extracellular oxidative enzymes involved in the white rot fungal lignin degradative process are laccases. This study presents evidence indicating that laccase has a role in PAH oxidation by white rot fungi. 36 refs., 5 figs., 1 tab.

  2. Vibrational Coupling

    SciTech Connect (OSTI)

    2011-01-01

    By homing in on the distribution patterns of electrons around an atom, a team of scientists team with Berkeley Lab's Molecular Foundry showed how certain vibrations from benzene thiol cause electrical charge to "slosh" onto a gold surface (left), while others do not (right). The vibrations that cause this "sloshing" behavior yield a stronger SERS signal.

  3. Hazardous materials: Microbiological decomposition. (Latest citations from the Biobusiness database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1993-12-01

    The bibliography contains citations concerning the decomposition of toxic materials by biological means. Bacteria, enzymes, and bioluminescence are among the methods discussed. Bacteria and enzymes that digest toluene, polychlorinated biphenyls (PCBs), selenium wastes, oil shale waste, uranium, oil sludge, pesticides, rubber wastes, and pentachlorophenol are discussed. Flavobacterium and white rot fungus are among the biological agents highlighted. (Contains 250 citations and includes a subject term index and title list.)

  4. Hazardous materials: Microbiological decomposition. (Latest citations from the Biobusiness database). NewSearch

    SciTech Connect (OSTI)

    Not Available

    1994-10-01

    The bibliography contains citations concerning the decomposition of toxic materials by biological means. Bacteria, enzymes, and bioluminescence are among the methods discussed. Bacteria and enzymes that digest toluene, polychlorinated biphenyls (PCBs), selenium wastes, oil shale waste, uranium, oil sludge, pesticides, rubber wastes, and pentachlorophenol are discussed. Flavobacterium and white rot fungus are among the biological agents highlighted. (Contains 250 citations and includes a subject term index and title list.)

  5. Phase behavior of nanoparticle/diblock copolymer in a selective solvent.

    SciTech Connect (OSTI)

    Lo, C.-T.; Lee, B.; Winans, R. E.; Thiyagarajan, P.

    2007-01-01

    Solvents used for controlling the self-assembly of polymer nanocomposites have a strong influence on the order-disorder and order-order transition temperatures. We have investigated the phase behavior of complexes composed of poly(styrene-b-2-vinylpyridine) (PS-PVP) and thiol-terminated PS stabilized Au nanoparticles in toluene-d (a good solvent for PS) by using small-angle neutron scattering. We observe that the morphologies of the neat and nanoparticle-containing polymer solutions strongly depend on the concentration of nanoparticles and temperature. Comparison of the phase diagrams of the neat and nanoparticle-containing polymer solutions as a function of temperature clearly shows dramatic shifts in the order-disorder and order-order transition temperatures. This dramatic effect can be understood by a model wherein the added nanoparticles that sequester in the preferred PS domains increase the interfacial curvature, leading to the observed changes in the nanostructure of the complex. Some effects are similar to those of the selective solvent such as toluene on the nanostructure of PS-PVP. Knowledge gained from these studies on the effects of nanoparticle concentration and temperature on the phase behavior of the polymer nanocomposites will be valuable for tailoring the physical properties of novel nanocomposites.

  6. Dynamics of polymer film formation during spin coating

    SciTech Connect (OSTI)

    Mouhamad, Y.; Clarke, N.; Jones, R. A. L.; Geoghegan, M.; Mokarian-Tabari, P.

    2014-09-28

    Standard models explaining the spin coating of polymer solutions generally fail to describe the early stages of film formation, when hydrodynamic forces control the solution behavior. Using in situ light scattering alongside theoretical and semi-empirical models, it is shown that inertial forces (which initially cause a vertical gradient in the radial solvent velocity within the film) play a significant role in the rate of thinning of the solution. The development of thickness as a function of time of a solute-free liquid (toluene) and a blend of polystyrene and poly(methyl methacrylate) cast from toluene were fitted to different models as a function of toluene partial pressure. In the case of the formation of the polymer blend film, a concentration-dependent (Huggins) viscosity formula was used to account for changes in viscosity during spin coating. A semi-empirical model is introduced, which permits calculation of the solvent evaporation rate and the temporal evolution of the solute volume fraction and solution viscosity.

  7. Probing the size and environment induced phase transformation in CdSe quantum dots

    SciTech Connect (OSTI)

    Karakoti, Ajay S.; Sanghavi, Shail P.; Nachimuthu, Ponnusamy; Yang, Ping; Thevuthasan, Suntharampillai

    2011-11-17

    The structural and electronic properties of CdSe quantum dots in toluene and drop-casted on Si wafer were investigated by in-situ micro X-ray diffraction, X-ray photoelectron spectroscopy and UV-Vis absorption and emission spectroscopy. The in-situ micro diffraction data show that the CdSe quantum dots capped with TOPO or hexadecylamine (HDA) in toluene exhibit predominantly wurtzite crystal structure, which undergoes a phase transformation to zinc blende crystal structure following drop casting on Si and this phase transition increases with decreasing the size of the CdSe quantum dots. Decreasing the size of quantum dots also increases the Se vacancies that facilitate the phase transformation. The X-ray photoelectron spectra show a systematic increase in the core level binding energies of Cd 3d and Se 3d, the band gap and the Cd/Se ratio as the size of the quantum dots decreases from 6.6nm to 2.1nm. This is attributed to the quantum confinement of CdSe crystallites by the capping ligands in toluene which increases with decreasing the size of the quantum dots. However, drop-casting quantum dots on Si alter the density and arrangement of capping ligands and solvent molecules on the quantum dots which causes significant phase transformation.

  8. HEAVY OIL PROCESS MONITOR: AUTOMATED ON-COLUMN ASPHALTENE PRECIPITATION AND RE-DISSOLUTION

    SciTech Connect (OSTI)

    John F. Schabron; Joseph F. Rovani Jr; Mark Sanderson

    2006-06-01

    About 37-50% (w/w) of the heptane asphaltenes from unpyrolyzed residua dissolve in cyclohexane. As pyrolysis progresses, this number decrease to below 15% as coke and toluene insoluble pre-coke materials appear. This solubility measurement can be used after coke begins to form, unlike the flocculation titration, which cannot be applied to multi-phase systems. Currently, the procedure for the isolation of heptane asphaltenes and the determination of the amount of asphaltenes soluble in cyclohexane spans three days. A more rapid method to measure asphaltene solubility was explored using a novel on-column asphaltene precipitation and re-dissolution technique. This was automated using high performance liquid chromatography (HPLC) equipment with a step gradient sequence using the solvents: heptane, cyclohexane, toluene:methanol (98:2). Results for four series of original and pyrolyzed residua were compared with data from the gravimetric method. The measurement time was reduced from three days to forty minutes. The separation was expanded further with the use of four solvents: heptane, cyclohexane, toluene, and cyclohexanone or methylene chloride. This provides a fourth peak which represents the most polar components, in the oil.

  9. Cis-Chlorobenzene dihydrodiol dehydrogenase (TcbB) from Pseudomonas sp. strain P51, expressed in Escherichia coli DH5{alpha}(pTCB149), catalyzes enantioselective dehydrogenase reactions

    SciTech Connect (OSTI)

    Raschke, H.; Fleischmann, T.; Meer, J.R. van der; Kohler, H.P.E.

    1999-12-01

    cis-Chlorobenzene dihydrodiol dehydrogenase (CDD) from Pseudomonas sp. strain P51, cloned into Escherichia coli DH5{alpha}(pTCB149) was able to oxidize cis-dihydrodihydroxy derivatives (cis-dihydrodiols) of dihydronaphthalene, indene, and four para-substituted toluenes to the corresponding catechols. During the incubation of a nonracemic mixture of cis-1,2-indandiol, only the (+)-cis-(1R,2S) enantiomer was oxidized; the (-)-cis-(S,2R) enantiomer remained unchanged, CDD oxidized both enantiomers of cis-1,2-dihydroxy-1,2,3,4-tetrahydronaphthalene, but oxidation of the (+)-cis-(1S,2R) enantiomer was delayed until the (-)-cis-(1R,2S) enantiomer was completely depleted. When incubated with nonracemic mixtures of para-substituted cis-toluene dihydrodiols, CDD always oxidized the major enantiomer at a higher rate than the minor enantiomer. When incubated with racemic 1-indanol, CDD enantioselectively transformed the (+)-(1S) enatiomer to 1-indanone. This stereoselective transformation shows that CDD also acted as an alcohol dehydrogenase. Additionally, CDD was able to oxidize (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene, (+)-cis-monochlorobiphenyl dihydrodiols, and (+)-cis-toluene dihydrodiol to the corresponding catechols.

  10. Mechanism of Efficient Anti-Markovnikov Olefin Hydroarylation Catalyzed by Homogeneous Ir(III) Complexes

    SciTech Connect (OSTI)

    Bhalla, Gaurav; Bischof, Steven M; Ganesh, Somesh K; Liu, Xiang Y; Jones, C J; Borzenko, Andrey; Tenn, William J; Ess, Daniel H; Hashiguchi, Brian G; Lokare, Kapil S; Leung, Chin Hin; Oxgaard, Jonas; Goddard, William A; Periana, Roy A

    2011-01-01

    The mechanism of the hydroarylation reaction between unactivated olefins (ethylene, propylene, and styrene) and benzene catalyzed by [(R)Ir(?-acac-O,O,C{sup 3})-(acac-O,O){sub 2}]{sub 2} and [R-Ir(acac-O,O){sub 2}(L)] (R = acetylacetonato, CH{sub 3}, CH{sub 2}CH{sub 3}, Ph, or CH{sub 2}CH{sub 2}Ph, and L = H{sub 2}O or pyridine) Ir(III) complexes was studied by experimental methods. The system is selective for generating the anti-Markovnikov product of linear alkylarenes (61:39 for benzene + propylene and 98:2 for benzene + styrene). The reaction mechanism was found to follow a rate law with first-order dependence on benzene and catalyst, but a non-linear dependence on olefin. {sup 13}C-labelling studies with CH{sub 3}{sup 13}CH{sub 2}-Ir-Py showed that reversible ?-hydride elimination is facile, but unproductive, giving exclusively saturated alkylarene products. The migration of the {sup 13}C-label from the ? to ?-positions was found to be slower than the C–H activation of benzene (and thus formation of ethane and Ph-d{sub 5}-Ir-Py). Kinetic analysis under steady state conditions gave a ratio of the rate constants for CH activation and ?-hydride elimination (k{sub CH}: k{sub ?}) of ~0.5. The comparable magnitude of these rates suggests a common rate determining transition state/intermediate, which has been shown previously with B3LYP density functional theory (DFT) calculations. Overall, the mechanism of hydroarylation proceeds through a series of pre-equilibrium dissociative steps involving rupture of the dinuclear species or the loss of L from Ph-Ir-L to the solvento, 16-electron species, Ph-Ir(acac-O,O){sub 2}-Sol (where Sol refers to coordinated solvent). This species then undergoes trans to cisisomerization of the acetylacetonato ligand to yield the pseudo octahedral species cis-Ph-Ir-Sol, which is followed by olefin insertion (the regioselective and rate determining step), and then activation of the C–H bond of an incoming benzene to generate the product and regenerate the catalyst.

  11. Flash pyrolysis and hydropyrolysis of biomass

    SciTech Connect (OSTI)

    Not Available

    1982-08-01

    Process chemistry data on the flash pyrolysis and hydropyrolysis of wood is being obtained in a 1'' downflow entrained tubular reactor. The data indicates that at residence times of <1 second, and 900 to 1000/sup 0/C and 500 psi pressure, the flash hydropyrolysis of wood yields mainly methane and water. As the residence time increases to >3 seconds, the products are methane and CO. Almost complete conversion of the carbon to methane and CO are obtained in these experiments. At lower temperatures, in the order of 800/sup 0/C, 500 psi and residence times <4 seconds, significant amounts of benzene and ethane are produced. The experimental process chemistry data have been used to design and evaluate two processes in a preliminary manner. One process converts wood to high BTU pipeline gas and the other to methanol and chemical feedstocks consisting of benzene and ethylene. Reasonable plant investments which compare favorably with coal conversion plant estimates are derived.

  12. Automobile proximity and indoor residential concentrations of BTEX and MTBE

    SciTech Connect (OSTI)

    Corsi, Dr. Richard; Morandi, Dr. Maria; Siegel, Dr. Jeffrey; Hun, Diana E

    2011-01-01

    Attached garages have been identified as important sources of indoor residential air pollution. However, the literature lacks information on how the proximity of cars to the living area affects indoor concentrations of gasoline-related compounds, and the origin of these pollutants. We analyzed data from the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study and evaluated 114 residences with cars in an attached garage, detached garage or carport, or without cars. Results indicate that homes with cars in attached garages were affected the most. Concentrations in homes with cars in detached garages and residences without cars were similar. The contribution from gasoline-related sources to indoor benzene and MTBE concentrations appeared to be dominated by car exhaust, or a combination of tailpipe and gasoline vapor emissions. Residing in a home with an attached garage could lead to benzene exposures ten times higher than exposures from commuting in heavy traffic.

  13. Collision dynamics of polyatomic molecules containing carbon rings at low temperatures

    SciTech Connect (OSTI)

    Li, Zhiying; Heller, Eric J.; Krems, Roman V.

    2014-09-14

    We explore the collision dynamics of complex hydrocarbon molecules (benzene, coronene, adamantane, and anthracene) containing carbon rings in a cold buffer gas of {sup 3}He. For benzene, we present a comparative analysis of the fully classical and fully quantum calculations of elastic and inelastic scattering cross sections at collision energies between 1 and 10 cm{sup ?1}. The quantum calculations are performed using the time-independent coupled channel approach and the coupled-states approximation. We show that the coupled-states approximation is accurate at collision energies between 1 and 20 cm{sup ?1}. For the classical dynamics calculations, we develop an approach exploiting the rigidity of the carbon rings and including low-energy vibrational modes without holonomic constraints. Our results illustrate the effect of the molecular shape and the vibrational degrees of freedom on the formation of long-lived resonance states that lead to low-temperature clustering.

  14. Reconstruction of ionization probabilities from spatially averaged data in N dimensions

    SciTech Connect (OSTI)

    Strohaber, J.; Kolomenskii, A. A.; Schuessler, H. A.

    2010-07-15

    We present an analytical inversion technique, which can be used to recover ionization probabilities from spatially averaged data in an N-dimensional detection scheme. The solution is given as a power series in intensity. For this reason, we call this technique a multiphoton expansion (MPE). The MPE formalism was verified with an exactly solvable inversion problem in two dimensions, and probabilities in the postsaturation region, where the intensity-selective scanning approach breaks down, were recovered. In three dimensions, ionization probabilities of Xe were successfully recovered with MPE from simulated (using the Ammosov-Delone-Krainov tunneling theory) ion yields. Finally, we tested our approach with intensity-resolved benzene-ion yields, which show a resonant multiphoton ionization process. By applying MPE to this data (which were artificially averaged), the resonant structure was recovered, which suggests that the resonance in benzene may have been observed in spatially averaged data taken elsewhere.

  15. Flash pyrolysis and hydropyrolysis of biomass

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.

    1982-04-01

    Process chemistry data on the flash pyrolysis and hydropyrolysis of wood is being obtained in a 1'' downflow entrained tubular reactor. The data indicates that at residence times of <1 second, and 900 to 1000/sup 0/C and 500 psi pressure, the flash hydropyrolysis of wood yields mainly methane and water. As the residence time increases to >3 seconds, the products are methane and CO. Almost complete conversion of the carbon to methane and CO are obtained in these experiments. At lower temperatures, in the order of 800/sup 0/C, 500 psi and residence times <4 seconds, significant amounts of benzene and ethane are produced. The experimental process chemistry data have been used to design and evaluate two processes in a preliminary manner. One process converts wood to high BTU pipeline gas and the other to methanol and chemical feedstocks consisting of benzene and ethylene. Reasonable plant investments which compare favorably with coal conversion plant estimates are derived.

  16. Graphene Oxide Catalyzed C-H Bond Activation: The Importance Oxygen

    Office of Scientific and Technical Information (OSTI)

    Functional Groups for Biaryl Construction (Journal Article) | SciTech Connect Graphene Oxide Catalyzed C-H Bond Activation: The Importance Oxygen Functional Groups for Biaryl Construction Citation Details In-Document Search Title: Graphene Oxide Catalyzed C-H Bond Activation: The Importance Oxygen Functional Groups for Biaryl Construction A heterogeneous, inexpensive and environment-friendly carbon catalytic system was developed for the C-H bond arylation of benzene resulting in the

  17. Organic molecules colliding with and desorbing from solid surfaces

    SciTech Connect (OSTI)

    Garrison, B.J.; Sundararam, V.; Taylor, R.S.

    1996-12-31

    The reactions induced by both 500 eV Ar bombardment of organic overlayers on Pt(111) and 20-60 eV benzene and phenyl radical scattering from a H-terminated diamond surface have been modeled with molecular dynamics simulations. We have used many-body potential developed by Brenner that allows for reactions among the particles. Examples of reactions observed in the simulations will be discussed.

  18. Molecular near-field antenna effect in resonance hyper-Raman scattering: Intermolecular vibronic intensity borrowing of solvent from solute through dipole-dipole and dipole-quadrupole interactions

    SciTech Connect (OSTI)

    Shimada, Rintaro; Hamaguchi, Hiro-o

    2014-05-28

    We quantitatively interpret the recently discovered intriguing phenomenon related to resonance Hyper-Raman (HR) scattering. In resonance HR spectra of all-trans-?-carotene (?-carotene) in solution, vibrations of proximate solvent molecules are observed concomitantly with the solute ?-carotene HR bands. It has been shown that these solvent bands are subject to marked intensity enhancements by more than 5 orders of magnitude under the presence of ?-carotene. We have called this phenomenon the molecular-near field effect. Resonance HR spectra of ?-carotene in benzene, deuterated benzene, cyclohexane, and deuterated cyclohexane have been measured precisely for a quantitative analysis of this effect. The assignments of the observed peaks are made by referring to the infrared, Raman, and HR spectra of neat solvents. It has been revealed that infrared active and some Raman active vibrations are active in the HR molecular near-field effect. The observed spectra in the form of difference spectra (between benzene/deuterated benzene and cyclohexane/deuterated cyclohexane) are quantitatively analyzed on the basis of the extended vibronic theory of resonance HR scattering. The theory incorporates the coupling of excited electronic states of ?-carotene with the vibrations of a proximate solvent molecule through solute–solvent dipole–dipole and dipole–quadrupole interactions. It is shown that the infrared active modes arise from the dipole–dipole interaction, whereas Raman active modes from the dipole–quadrupole interaction. It is also shown that vibrations that give strongly polarized Raman bands are weak in the HR molecular near-field effect. The observed solvent HR spectra are simulated with the help of quantum chemical calculations for various orientations and distances of a solvent molecule with respect to the solute. The observed spectra are best simulated with random orientations of the solvent molecule at an intermolecular distance of 10 Å.

  19. (E)-4-[(4-nitrophenyl)diazenyl]phenyl anthracene-9-carboxylate.

    SciTech Connect (OSTI)

    Vance, Andrew L.; Zifer, Thomas; Nichol, Jessica L.; Rodriguez, Mark Andrew; Leonard, Francois Leonard; Wong, Bryan Matthew

    2008-10-01

    In the title compound, C{sub 27}H{sub 17}N{sub 3}O{sub 4}, the azo group displays a trans conformation and the dihedral angles between the central benzene ring and the pendant anthracene and nitrobenzene rings are 82.94 (7) and 7.30 (9){sup o}, respectively. In the crystal structure, weak C-H...O hydrogen bonds, likely associated with a dipole moment present on the molecule, help to consolidate the packing.

  20. Integrated experimental and theoretical study of the thermophysical properties of fluid mixtures. Annual report, September 1984-September 1985

    SciTech Connect (OSTI)

    Haynes, W.M.

    1985-01-01

    This report summarizes the work done in the twelve months from September 30, 1984. Results include: PVT data for methanol (to 300/sup 0/C) and benzene (to 450/sup 0/C); basic studies of a fluid in nonequilibrium; high temperature VLE data for CO/sub 2//butane; viscosity experimental data and predictive procedures on association for coal liquids, and results on the phenomenon of shear induced phase changes.

  1. Synthesis of N-formyl-3,4-di-t-butoxycarbonyloxy-6-(trimethylstannyl)-L-phenylalanine ethyl ester and its regioselective radiofluorodestannylation to 6- .sup.18 F!fluoro-1-dopa

    DOE Patents [OSTI]

    Satyamurthy, Nagichettiar; Barrio, Jorge R.; Bishop, Allyson J.; Namavari, Mohammad; Bida, Gerald T.

    1996-01-01

    A process for forming a 6-fluoro derivative of compounds in the L-Dopa family comprising the steps of protecting the groups attached to the benzene ring in the compound followed by serially reacting the protected compound with (a) iodine and silver trifluoroacetic acid; (b) Bb.sub.3 ; (c) dit-butyldicarbonate; (d) hexamethyltin; (e) a fluoro compound; (f) hydrobromic acid; and (g) raising the pH to .ltoreq.7.

  2. Synthesis of N-formyl-3,4-di-t-butoxycarbonyloxy-6(trimethylstannyl)-L-phenylalanine ethyl ester and its regioselective radiofluorodestannylation to 6-[{sup 18}F]fluoro-1-dopa

    DOE Patents [OSTI]

    Satyamurthy, N.; Barrio, J.R.; Bishop, A.J.; Namavari, M.; Bida, G.T.

    1996-04-23

    A process is revealed for forming a 6-fluoro derivative of compounds in the L-Dopa family comprising the steps of protecting the groups attached to the benzene ring in the compound followed by serially reacting the protected compound with (a) iodine and silver trifluoroacetic acid; (b) Bb{sub 3}; (c) dit-butyldicarbonate; (d) hexamethyltin; (e) a fluoro compound; (f) hydrobromic acid; and (g) raising the pH to {<=}7. 1 fig.

  3. Features of the spectral dependences of transmittance of organic semiconductors based on tert-butyl substituted lutetium phthalocyanine molecules

    SciTech Connect (OSTI)

    Belogorokhov, I. A.; Tikhonov, E. V.; Dronov, M. A.; Belogorokhova, L. I.; Ryabchikov, Yu. V.; Tomilova, L. G.; Khokhlov, D. R.

    2011-11-15

    Vibronic properties of organic semiconductors based on tert-butyl substituted phthalocyanine lutetium diphthalocyanine molecules are studied by IR and Raman spectroscopy. It is shown that substitution of several carbon atoms in initial phthalocyanine (Pc) ligands with {sup 13}C isotope atoms causes a spectral shift in the main absorption lines attributed to benzene, isoindol, and peripheral C-H groups. A comparison of spectral characteristics showed that the shift can vary from 3 to 1 cm{sup -1}.

  4. Towards Using Molecular States as Qubits

    SciTech Connect (OSTI)

    Goswami, Debabrata; Goswami, Tapas; Kumar, S. K. Karthick; Das, Dipak K.

    2011-09-23

    Molecular systems are presented as possible qubit systems by exploring non-resonant molecular fragmentation of n-propyl benzene with femtosecond laser pulses as a model case. We show that such laser fragmentation process is dependent on the phase and polarization characteristics of the laser. The effect of the chirp and polarization of the femtosecond pulse when applied simultaneously is mutually independent of each other, which makes chirp and polarization as useful 'logic' implementing parameters for such molecular qubits.

  5. Neutron Cross-Section Measurements on Structural Materials at ORELA

    SciTech Connect (OSTI)

    Guber, Klaus H; Koehler, Paul; Wiarda, Dorothea; Harvey, John A

    2011-01-01

    Neutron capture experiments, using isotopically enriched and natural samples of chromium and titanium, were performed on flight paths 6 and 7 at the 40 m flight station of ORELA. The experimental data were acquired using a pair of deuterated benzene detectors employing the now well-established pulse-height-weighting technique. These data were complemented by new total cross-section measurements where no useful previous data were available.

  6. Liquid electrode

    DOE Patents [OSTI]

    Ekechukwu, Amy A.

    1994-01-01

    A dropping electrolyte electrode for use in electrochemical analysis of non-polar sample solutions, such as benzene or cyclohexane. The liquid electrode, preferably an aqueous salt solution immiscible in the sample solution, is introduced into the solution in dropwise fashion from a capillary. The electrolyte is introduced at a known rate, thus, the droplets each have the same volume and surface area. The electrode is used in making standard electrochemical measurements in order to determine properties of non-polar sample solutions.

  7. Microsoft Word - S11432_2013Annual Rpt.docx

    Office of Legacy Management (LM)

    425 4.0 References Adrian, L. and H. Gorisch, 2002." Microbial transformation of chlorinated benzenes under anaerobic conditions," in Research in Microbiology 153, pp. 131-137; Elsevier, February 14. ATSDR (Agency for Toxic Substances and Disease Registry), 2007. Analyses of Groundwater Flow, Contaminant Fate and Transport, and Distribution of Drinking Water at Tarawa Terrace and Vicinity, U.S. Marine Corps Base Camp Lejeune, North Carolina: Historical Reconstruction and Present Day

  8. Process for reducing organic compounds with calcium, amine, and alcohol

    DOE Patents [OSTI]

    Benkeser, R.A.; Laugal, J.A.; Rappa, A.

    1985-08-06

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about [minus]10 C to about 30 C or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  9. Process for reducing organic compounds with calcium, amine, and alcohol

    DOE Patents [OSTI]

    Benkeser, Robert A.; Laugal, James A.; Rappa, Angela

    1985-01-01

    Olefins are produced by contacting an organic compound having at least one benzene ring with calcium metal, ethylenediamine, a low molecular weight aliphatic alcohol, and optionally a low molecular weight aliphatic primary amine, and/or an inert, abrasive particulate substance. The reduction is conducted at temperatures ranging from about -10.degree. C. to about 30.degree. C. or somewhat higher. Substantially all of the organic compounds are converted to corresponding cyclic olefins, primarily diolefins.

  10. Source Apportionment of Stack Emissions from Research and Development Facilities Using Positive Matrix Factorization

    SciTech Connect (OSTI)

    Ballinger, Marcel Y.; Larson, Timothy V.

    2014-08-19

    Emissions from research and development (R&D) facilities are difficult to characterize due to the wide variety of processes used, changing nature of research, and large number of chemicals. Positive matrix factorization (PMF) was applied to volatile organic compounds (VOCs) concentrations measured in the main exhaust stacks of four different R&D buildings to identify the number and composition of major contributing sources. PMF identified from 9-11 source-related factors contributing to the stack emissions depending on the building. The factors that were similar between buildings were major contributors to trichloroethylene (TCE), acetone, and ethanol emissions. Several other factors had similar profiles for two or more buildings but not for all four. One factor for each building was a combination of p/m-xylene, o-xylene and ethylbenzene. At least one factor for each building was identified that contained a broad mix of many species and constraints were used in PMF to modify the factors to resemble more closely the off-shift concentration profiles. PMF accepted the constraints with little decrease in model fit. Although the PMF model predicted the profiles of the off-shift samples, the percent of total emissions was under-predicted by the model versus the measured data.

  11. A novel process for upgrading heavy oil emulsions

    SciTech Connect (OSTI)

    Ng, F.T.T.; Rintjema, R.T.

    1994-12-31

    Canada has extensive reserves of high sulfur heavy oils. These heavy oils are recovered primarily by steam injection techniques. As a result, the heavy oils are obtained as emulsions at well-heads. The heavy oils, being high in sulfur and metals, and low in hydrogen to carbon atomic ratio, require upgrading such as desulfurization and hydrocracking before it can be used in conventional refineries. Conventional emulsion treatment and desulfurization technology require multistage processing. Thus, alternative technologies for processing heavy oil emulsions would be attractive. The authors have recently developed a novel single stage process for upgrading emulsions via activation of water to provide hydrogen in situ for catalytic desulfurization and hydrocracking. Current work is focused on the desulfurization aspect of upgrading, using benzothiophene as the model sulfur compound and molybdic acid as the catalyst. At 340 C and a CO loading pressure of 600 psi, up to 86% sulfur removal was obtained. As well, in situ generated H{sub 2} was found to be more active than externally supplied molecular H{sub 2}. A likely pathway for desulfurization of benzothiophene was via the initial hydrogenation of benzothiophene to dihydrobenzothiophene followed by hydrogenolysis to give ethylbenzene and H{sub 2}S.

  12. Efficiency of clay-TiO2 nanocomposites on the photocatalytic eliminationof a model hydrophobic air pollutant

    SciTech Connect (OSTI)

    Kibanova, Daria; Cervini-Silva, Javiera; Destaillats, Hugo

    2009-01-01

    Clay-supported TiO2 photocatalysts can potentially improve the performance of air treatment technologies via enhanced adsorption and reactivity of target volatile organic compounds (VOCs). In this study, a bench-top photocatalytic flow reactor was used to evaluate the efficiency of hectorite-TiO2 and kaolinite-TiO2, two novel composite materials synthesized in our laboratory. Toluene, a model hydrophobic VOC and a common indoor air pollutant, was introduced in the air stream at realistic concentrations, and reacted under UVA (gamma max = 365 nm) or UVC (gamma max = 254 nm) irradiation. The UVC lamp generated secondary emission at 185 nm, leading to the formation of ozone and other short-lived reactive species. Performance of clay-TiO2 composites was compared with that of pure TiO2 (Degussa P25), and with UV irradiation in the absence of photocatalyst under identical conditions. Films of clay-TiO2 composites and of P25 were prepared by a dip-coating method on the surface of Raschig rings, which were placed inside the flow reactor. An upstream toluene concentration of ~;;170 ppbv was generated by diluting a constant flow of toluene vapor from a diffusion source with dry air, or with humid air at 10, 33 and 66percent relative humidity (RH). Toluene concentrations were determined by collecting Tenax-TA (R) sorbent tubes downstream of the reactor, with subsequent thermal desorption -- GC/MS analysis. The fraction of toluene removed, percentR, and the reaction rate, Tr, were calculated for each experimental condition from the concentration changes measured with and without UV irradiation. Use of UVC light (UV/TiO2/O3) led to overall higher reactivity, which can be partially attributed to the contribution of gas phase reactions by short-lived radical species. When the reaction rate was normalized to the light irradiance, Tr/I gamma, the UV/TiO2 reaction under UVA irradiation was more efficient for samples with a higher content of TiO2 (P25 and Hecto-TiO2), but not for Kao-TiO2. In all cases, reaction rates peaked at 10percent RH, with Tr values between 10 and 50percent higher than those measured under dry air. However, a net inhibition was observed as RH increased to 33percent and 66percent, indicating that water molecules competed effectively with toluene for reactive surface sites and limited the overall photocatalytic conversion. Compared to P25, inhibition by co-adsorbed water was less significant for Kao-TiO2 samples, but was more dramatic for Hecto-TiO2 due to the high water uptake capacity of hectorite.

  13. Hydrogen-Bond Networks: Strengths of Different Types of Hydrogen Bonds and An Alternative to the Low Barrier Hydrogen-Bond Proposal

    SciTech Connect (OSTI)

    Shokri, Alireza; Wang, Yanping; O'Doherty, George A.; Wang, Xue B.; Kass, Steven R.

    2013-11-27

    We report quantifying the strengths of different types of hydrogen bonds in hydrogen bond networks (HBNs) via measurement of the adiabatic electron detachment energy of the conjugate base of a small covalent polyol model compound (i.e., (HOCH2CH2CH(OH)CH2)2CHOH) in the gas phase and the pKa of the corresponding acid in DMSO. The latter result reveals that the hydrogen bonds to the charged center and those that are one solvation shell further away (i.e., primary and secondary) provide 5.3 and 2.5 pKa units of stabilization per hydrogen bond in DMSO. Computations indicate that these energies increase to 8.4 and 3.9 pKa units in benzene and that the total stabilizations are 16 (DMSO) and 25 (benzene) pKa units. Calculations on a larger linear heptaol (i.e., (HOCH2CH2CH(OH)CH2CH(OH)CH2)2CHOH) reveal that the terminal hydroxyl groups each contribute 0.6 pKa units of stabilization in DMSO and 1.1 pKa units in benzene. All of these results taken together indicate that the presence of a charged center can provide a powerful energetic driving force for enzyme catalysis and conformational changes such as in protein folding due to multiple hydrogen bonds in a HBN.

  14. Health-hazard evaluation report HETA 84-033-1576, Airco Carbon, St. Marys, Pennsylvania

    SciTech Connect (OSTI)

    Hartle, R.W.; Morawetz, J.S.

    1985-09-01

    Environmental and breathing-zone samples were analyzed for polynuclear aromatic hydrocarbons (PAH), total particulates, and respirable free silica at the Airco Company (SIC-3624), Saint Marys, Pennsylvania in January, 1984. The evaluation was requested confidentially because of concern over exposures to soot, coal tar pitch volatiles, and sand in the car bottom and sagger bake operations. Forty-three employees were interviewed. Two of 19 total particulate samples exceeded the OSHA standard of 15 milligrams per cubic meter (mg/m3), 17.3 and 32.7 mg/m3. Benzene soluble fractions ranged from 0.5 to 5.0 mg/m3. The OSHA standard for benzene soluble fractions is 0.2 mg/m3. Two of seven samples of silica were above the limit of detection, 0.09 and 0.06 mg/m3. In bulk samples, the benzene soluble fractions ranged from 0.44 to 860 mg/gram and the PAH content from 0 to 26,124 micrograms per gram. Employees working in the bake areas reported a significant excess incidence of symptoms such as skin, nose and eye irritation, cough, sore or dry throat, chest tightness, and breathing difficulty. The authors conclude that a health hazard exists at the facility. Recommendations include enclosing vehicles used in moving electrodes, cleaning up spilled dust, and controlling fumes emitted from the sagger kilns.

  15. ELECTRON-DRIVEN REACTIONS IN PROTO-PLANETARY ATMOSPHERES: METASTABLE ANIONS OF GASEOUS o-BENZYNE

    SciTech Connect (OSTI)

    Carelli, F.; Sebastianelli, F.; Baccarelli, I.; Gianturco, F. A.

    2010-03-20

    In this paper, we present an investigation into low-energy electron scattering (E < 15 eV) processes from a specific benzene-like polyatomic target such as ortho-benzyne, o-C{sub 6}H{sub 4}({sup 1}SIGMA), in order to gain a better understanding of the effects that possible low-lying metastable electron-attachment states could have on its nuclear fragmentation dynamics. The current importance of the dynamical evolution of this molecule lies in the fact that o-C{sub 6}H{sub 4} is considered to be relevant for the circumstellar synthesis of large polycyclic aromatic hydrocarbons (PAHs), as a precursor for C{sub 6}H{sub 6} production via ion-based ring closure reaction from C{sub 2}H{sub 2}. Our parameter-free scattering calculations are performed within the molecular reference frame, where we obtain the metastable anionic states for the nuclear equilibrium configuration and further characterize the properties of such transient anions with respect to those found earlier for the benzene molecule. Our quantum studies indicate that o-C{sub 6}H{sub 4} is a more efficient producer of compact, fairly long-lived anionic intermediates than benzene itself; hence, this should more rapidly enter the chemical reaction cycles of PAHs formation, thereby disappearing from possible direct observation as a stable anion.

  16. An Assessment of Density Functional Methods for Potential Energy Curves of Nonbonded Interactions: The XYG3 and B97-D Approximations

    SciTech Connect (OSTI)

    Vazquez-Mayagoitia, Alvaro; Sherrill, David; Apra, Edoardo; Sumpter, Bobby G

    2010-01-01

    A recently proposed double-hybrid functional called XYG3 and a semilocal GGA functional (B97-D) with a semiempirical correction for van der Waals interactions have been applied to study the potential energy curves along the dissociation coordinates of weakly bound pairs of molecules governed by London dispersion and induced dipole forces. Molecules treated in this work were the parallel sandwich, T-shaped, and parallel-displaced benzene dimer, (C6H6)2; hydrogen sulfide and benzene, H2S C6H6; methane and benzene, CH4 C6H6; the methane dimer, (CH4)2; and the pyridine dimer, (C5H5N)2. We compared the potential energy curves of these functionals with previously published benchmarks at the coupled cluster singles, doubles, and perturbative triplets [CCSD(T)] complete-basis-set limit. Both functionals, XYG3 and B97-D, exhibited very good performance, reproducing accurate energies for equilibrium distances and a smooth behavior along the dissociation coordinate. Overall, we found an agreement within a few tenths of one kcal mol-1 with the CCSD(T) results across the potential energy curves.

  17. Characterization of Cerro Negro crude. Part II. Chemical analysis. [Project sponsored by Bartlesville Energy Technology Center and Institute de Tecnologico del Venezolana Petroleo

    SciTech Connect (OSTI)

    Sturm, G.P. Jr.; Grindstaff, Q.G.; Hirsch, D.E.; Scheppele, S.E.; Hazos, M.

    1981-09-01

    The cooperative research program is explained in Part I. An evaluation is presented of the resolution attained in the separation of a 425 to 550/sup 0/C petroleum distillate fraction according to compound classes using 2 chromatographic methods. Samples were separated by high performance liquid chromatography using 2 columns in series containing 2,4-dinitroanalinopropyl silica and silica, respectively. Initial elution was attained using 1% methylene chloride in pentane followed by a linear gradient up to 30% methylene chloride. In the 2nd method, developed in the American Petroleum Institute's Research Project 60, fractions designated as saturates, monoaromatics, diaromatics, and polyaromatics were collected froma dual silica/alumina column using step gradient elution with pentane, 5% benzene in pentane, 15% benzene in pentane, and 20% ethyl ether, 20% benzene, 60% methanol, followed by pure methanol. The results wil be used to evaluate the quality of the separation in terms of the success in producing fractions containing similar compound classes. 1 figure, 4 tables.

  18. Flash pyrolysis of biomass with reactive and non-reactive gases

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.T.; Sundaram, M.S.

    1984-03-01

    The process chemistry of the flash pyrolysis of biomass (wood) with the reactive gases, H/sub 2/ and CH/sub 4/ and with the non-reactive gases He and N/sub 2/ is being determined in an 1'' downflow tubular reactor at pressures from 20 to 1000 psi and temperatures from 600 to 1000/sup 0/C. With hydrogen, flash hydropyrolysis leads to high yields of ethylene, benzene and CO which can be used for the production of valuable chemical feedstocks and methanol transportation fuel. At reactor conditions of 50 psi and 1000/sup 0/C and approximately 1 sec residence time, the ethylene yield based on pine wood carbon conversion is 27%, for benzene it is 25% and for CO the yield is 39%, indicating that over 90% of the carbon in pine is converted to valuable products. Pine wood produces higher yields of hydrocarbon products than Douglas fir wood. The yield of ethylene is 2.3 times higher with methane than with helium or nitrogen, thus indicating a free radical reaction between CH/sub 4/ and the pyrolyzed wood. There appears to be no net production or consumption of methane. A preliminary process design and analysis indicate an economically competitive system for the production of ethylene, benzene and methanol based on the methanolysis of wood. 7 references, 13 figures, 1 table.

  19. Flash pyrolysis of biomass with reactive and non-reactive gases. Summary report, March 1982-March 1983

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.T.; Sundaram, M.S.

    1983-03-01

    The process chemistry of the flash pyrolysis of biomass (wood) with the reactive gases, H/sub 2/ and CH/sub 4/ and with the non-reactive gas He is being determined in a 1'' downflow tubular reactor at pressures from 20 to 1000 psi and temperatures from 600 to 1000/sup 0/C. With hydrogen, flash hydropyrolysis leads to high yields of methane and CO which can be used for SNG and methanol production. With methane, flash methanolysis of wood, leads to high yields of ethylene, benzene and CO which can be used for the production of valuable feedstocks and methanol fuel. At reactor conditions of 50 psi and 1000/sup 0/C and approximately 1 sec residence time, the ethylene yield based on wood carbon converted is 22%, benzene 12% and the CO yield is 48%. The yield of ethylene is 2.2 times higher with methane than with helium, thus indicating a free radical rection between CH/sub 4/ and the pyrolyzed wood. A preliminary process analysis indicates an economically competitive process for the production of ethylene, benzene and methanol based on the methanolysis of wood. It is recommended to further develop the data base for the flash pyrolysis of wood and other biomass materials with methane as well as with other reactive gases (e.g. CO and CO/sub 2/) and determine the role of the hemi-cellulose and lignin in the formation of these valuable fuels and feedstocks.

  20. Feet on the potential energy surface, head in the pi clouds

    SciTech Connect (OSTI)

    Smith, Quentin

    2012-07-12

    This work presents explorations of the potential energy surface of clusters of atoms and of the interactions between molecules. First, structures of small aluminum clusters are examined and classified as ground states, transition states, or higher-order saddle points. Subsequently, the focus shifts to dispersion-dominated π-π interactions when the potential energy surfaces of benzene, substituted benzene, and pyridine dimers are explored. Because DNA nucleotide bases can be thought of as substituted heterocycles, a natural extension of the substituted benzene and pyridine investigations is to model paired nucleotide bases. Finally, the success of the dispersion studies inspires the development of an extension to the computational method used, which will enable the dispersion energy to be modeled – and the potential energy surface explored – in additional chemical systems. The effective fragment potential (EFP) method is described, as well as various quantum mechanical methods. An ab inito quantum mechanical study of 13-atom aluminum clusters is described. EFP studies of aromatic dimers are reported in which dispersion energy makes a significant contribution to the attraction between monomers. Theory and code development toward a means of computing dispersion energy in mixed ab inito-EFP systems are described.

  1. Octamethyl-octaundecylcyclo[8]pyrrole: A Promising Sulfate Anion Extractant

    SciTech Connect (OSTI)

    Eller, Leah R; Stepien, Marcin; Fowler, Christopher J; Lee, Jeong Tae; Sessler, Jonathan L.; Moyer, Bruce A

    2008-01-01

    The diprotonated form of an organic-solubilized cyclo[8]pyrrole derivative, bearing eight undecyl chains on the {beta}-pyrrolic positions, was found to extract sulfate anion effectively from neutral aqueous media into a toluene organic phase. The kinetics of sulfate anion exchange between the two phases were found to be exceedingly slow in the absence of the phase-transfer catalyst, Aliquat 336-nitrate (A336N), but appreciable in its presence. The bisnitrate anion bound form of this cyclo[8]pyrrole could be generated in situ by subjecting the toluene phase containing initially 0.5 mM of the sulfate anion bound form and 0.1 mM trioctylamine (TOA) to successive equilibrations with aqueous 0.1 M HNO{sub 3} until sulfate was no longer detected in the aqueous phase. This bisnitrate complex, when studied as a 0.5 mM solution in toluene in the presence of 0.1 mM (TOAH){sup +}(NO{sub 3}{sup -}), was also found to be an effective extractant for sulfate anion. D{sub SO4} values of 0.001 and 1000 were observed at 1 M NaNO{sub 3}(aq) and 0.3 mM NaNO{sub 3}(aq), respectively, and the logarithm of the conditional exchange constant, log(K{prime}{sub exch}), was calculated to be 4.9 {+-} 0.4. The present cyclo[8]pyrrole system is thus noteworthy as being the first synthetic receptor that displays a high selectivity for sulfate anion in the presence of excess nitrate under conditions of solvent extraction.

  2. Synthesis and characterization of a series of Group 4 phenoxy-thiol derivatives

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Boyle, Timothy J.; Neville, Michael L.; Parkes, Marie V.

    2016-02-11

    In this study, a series of Group 4 phenoxy-thiols were developed from the reaction products of a series of metal tert-butoxides ([M(OBut)4]) with four equivalents of 4-mercaptophenol (H-4MP). The products were found by single crystal X-ray diffraction to adopt the general structure [(HOBut)(4MP)3M(μ-4MP)]2 [where M = Ti (1), Zr (2), Hf (3)] from toluene and [(py)2M(4MP)] where M = Ti (4), Zr (5) and [(py)(4MP)3Hf(μ-4MP)]2 (6) from pyridine (py). Varying the [Ti(OR)4] precursors (OR = iso-propoxide (OPri) or neo-pentoxide (ONep)) in toluene led to [(HOR)(4MP)3Ti(μ-4MP)]2 (OR = OPri (7), ONep (8)), which were structurally similar to 1. Lower stoichiometric reactionsmore » in toluene led to partial substitution by the 4MP ligands yielding [H][Ti(μ-4MP)(4MP)(ONep)3]2 (9). Independent of the stoichiometry, all of the Ti derivatives were found to be red in color, whereas the heavier congeners were colorless. Attempts to understand this phenomenon led to investigation with a series of varied –SH substituted phenols. From the reaction of H-2MP and H-3MP (2-mercaptophenol and 3-mercaptophenol, respectively), the isolated products had identical arrangements: [(ONep)2(2MP)Ti(μ,η2-2MP)]2 (10) and [(HOR)(3MP)M(μ-3MP)]2 (M/OR = Ti/ONep (11); Zr/OBut (12)) with a similar red color. Based on the simulated and observed UV–Vis spectra, it was reasoned that the color was generated due to a ligand-to-metal charge transfer for Ti that was not available for the larger congeners.« less

  3. Pervaporation separation of ethanol-water mixtures using polyacrylic acid composite membranes

    DOE Patents [OSTI]

    Neidlinger, H.H.

    1985-05-07

    Synthetic, organic, polymeric membranes were prepared from polyacrylic acid salts for use with pervaporation apparatus in the separation of ehthanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanata solution, after which the prepared membrane was heat-cured. The resulting membrane structure showed selectivity in permeating water over a wide range of feed concentrations. 4 tabs.

  4. Pervaporation separation of ethanol-water mixtures using polyethylenimine composite membranes

    DOE Patents [OSTI]

    Neidlinger, H.H.; Schissel, P.O.; Orth, R.A.

    1985-06-19

    Synthetic, organic, polymeric membranes were prepared from polyethylenimine for use with pervaporation apparatus in the separation of ethanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanate solution, after which the prepared membrane was heat-cured. The resulting membrane structures showed high selectivity in permeating ethanol or water over a wide range of feed concentrations. 2 tabs.

  5. Cascaded organic rankine cycles for waste heat utilization

    DOE Patents [OSTI]

    Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

    2011-05-17

    A pair of organic Rankine cycle systems (20, 25) are combined and their respective organic working fluids are chosen such that the organic working fluid of the first organic Rankine cycle is condensed at a condensation temperature that is well above the boiling point of the organic working fluid of the second organic Rankine style system, and a single common heat exchanger (23) is used for both the condenser of the first organic Rankine cycle system and the evaporator of the second organic Rankine cycle system. A preferred organic working fluid of the first system is toluene and that of the second organic working fluid is R245fa.

  6. Pervaporation separation of ethanol-water mixtures using polyethylenimine composite membranes

    DOE Patents [OSTI]

    Neidlinger, H.H.; Schissel, P.O.; Orth, R.A.

    1987-04-21

    Synthetic, organic, polymeric membranes were prepared from polyethylenimine for use with pervaporation apparatus in the separation of ethanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanate solution, after which the prepared membrane was heat-cured. The resulting membrane structures showed high selectivity in permeating ethanol or water over a wide range of feed concentrations.

  7. Process to recycle shredder residue

    DOE Patents [OSTI]

    Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.

    2001-01-01

    A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

  8. Thermal conductivities of Wilsonville solvent and Wilsonville solvent/Illinois No. 6 coal slurry. [Wilsonville solvent

    SciTech Connect (OSTI)

    Wilson, J.H.; Mrochek, J.E.; Johnson, J.K.

    1984-01-01

    Thermal conductivities of a Wilsonville solvent and of a slurry prepared from this solvent and Illinois No. 6 coal have been measured at temperatures from 295 up to 500 K. With increasing temperature, the thermal conductivity varied from 1.23 to 1.02 mW cm/sup -1/ K/sup -1/ (296 to 438 K) and from 1.51 to 1.02 mW cm/sup -1/ K/sup -1/ (295 to 505 K) for the solvent and the slurry, respectively. At room temperature, measurements on toluene were accurate to within 3% of literature values. 18 references, 9 figures, 7 tables.

  9. Electrically conductive doped block copolymer of polyacetylene and polyisoprene

    DOE Patents [OSTI]

    Aldissi, Mahmoud

    1985-01-01

    An electrically conductive block copolymer of polyisoprene and polyacetyl and a method of making the same are disclosed. The polymer is prepared by first polymerizing isoprene with n-butyllithium in a toluene solution to form an active isoprenyllithium polymer. The active polymer is reacted with an equimolar amount of titanium butoxide and subsequently exposed to gaseous acetylene. A block copolymer of polyisoprene and polyacetylene is formed. The copolymer is soluble in common solvents and may be doped with I.sub.2 to give it an electrical conductivity in the metallic regime.

  10. Electrically conductive doped block copolymer of polyacetylene and polyisoprene. [Soluble in organic solvents

    DOE Patents [OSTI]

    Aldissi, M.

    1984-06-27

    An electrically conductive block copolymer of polyisoprene and polyacetylene and a method of making the same are disclosed. The polymer is prepared by first polymerizing isoprene with n-butyllithium in a toluene solution to form an active isoprenyllithium polymer. The active polymer is reacted with an equimolar amount of titanium butoxide and subsequently exposed to gaseous acetylene. A block copolymer of polyisoprene and polyacetylene is formed. The copolymer is soluble in common solvents and may be doped with I/sub 2/ to give it an electrical conductivity in the metallic regime.

  11. Process for fullerene functionalization

    DOE Patents [OSTI]

    Cahill, P.A.; Henderson, C.C.

    1995-12-12

    Di-addended and tetra-addended Buckminster fullerenes are synthesized through the use of novel organoborane intermediates. The C{sub 60}, C{sub 70}, or higher fullerene is reacted with a borane such as BH{sub 3} in a solvent such as toluene to form an organoborane intermediate. Reaction of the organoborane such as hydrolysis with water or alcohol results in the product di-addended and tetra-addended fullerene in up to 30% yields. Dihydrofullerenes and tetrahydrofullerenes are produced by the process of the invention. 7 figs.

  12. Process for fullerene functionalization

    DOE Patents [OSTI]

    Cahill, Paul A.; Henderson, Craig C.

    1995-01-01

    Di-addended and tetra-addended Buckminster fullerenes are synthesized through the use of novel organoborane intermediates. The C.sub.60, C.sub.70, or higher fullerene is reacted with a borane such as BH.sub.3 in a solvent such as toluene to form an organoborane intermediate. Reaction of the organoborane such as hydrolysis with water or alcohol results in the product di-addended and tetra-addended fullerene in up to 30% yields. Dihydrofullerenes and tetrahydrofullerenes are produced by the process of the invention.

  13. Poly(ethylene oxide) functionalization

    DOE Patents [OSTI]

    Pratt, Russell Clayton

    2014-04-08

    A simple procedure is provided by which the hydroxyl termini of poly(ethylene oxide) can be appended with functional groups to a useful extent by reaction and precipitation. The polymer is dissolved in warmed toluene, treated with an excess of organic base and somewhat less of an excess of a reactive acylating reagent, reacted for several hours, then precipitated in isopropanol so that the product can be isolated as a solid, and salt byproducts are washed away. This procedure enables functionalization of the polymer while not requiring laborious purification steps such as solvent-solvent extraction or dialysis to remove undesirable side products.

  14. Superfund Record of Decision (EPA Region 2): Love Canal (93rd Street School), Niagara County, City of Niagara Falls, NY. (Third remedial action), (amendment), May 1991. Final report

    SciTech Connect (OSTI)

    Not Available

    1991-05-15

    The Love Canal (93rd Street) site is an inactive hazardous waste site located in Niagara Falls, New York. The 19-acre 93rd Street School site, one of several operable units for the Love Canal Superfund site, is the focus of the Record of Decision (ROD). The fill material is reported to contain fly ash and BHC (a pesticide) waste. The ROD amends the 1988 ROD, and addresses final remediation of onsite contaminated soil through excavation and offsite disposal. The primary contaminants of concern affecting the soil are VOCs including toluene and xylenes; other organics including PAHs and pesticides; and metals including arsenic, chromium, and lead.

  15. Testing of a model to estimate vapor concentration of various organic chemicals. Master's thesis

    SciTech Connect (OSTI)

    Bakalyar, S.M.

    1990-01-01

    A model developed by Dr. Parker C. Reist to predict the build-up and decay rates of vapor concentrations following a chemical spill and clean-up was tested. The chemicals tested were: acetone, butyl acetate, ethyl acetate, hexane, methylene chloride, methyl ethyl ketone, and toluene. The evaporation rates of these chemicals were determined both by prediction, using a model developed by I. Kawamura and D. Mackay, and empirically and these rates were used in the Reist model. Chamber experiments were done to measure actual building-up and decay of vapor concentrations for simulated spills and simulated clean-up.

  16. Catalyst system and process for benzyl ether fragmentation and coal liquefaction

    DOE Patents [OSTI]

    Zoeller, Joseph Robert (Kingsport, TN)

    1998-04-28

    Dibenzyl ether can be readily cleaved to form primarily benzaldehyde and toluene as products, along with minor amounts of bibenzyl and benzyl benzoate, in the presence of a catalyst system comprising a Group 6 metal, preferably molybdenum, a salt, and an organic halide. Although useful synthetically for the cleavage of benzyl ethers, this cleavage also represents a key model reaction for the liquefaction of coal; thus this catalyst system and process should be useful in coal liquefaction with the advantage of operating at significantly lower temperatures and pressures.

  17. Organic Rankine-Cycle Power Systems Working Fluids Study: Topical report No. 3, 2-methylpyridine/water

    SciTech Connect (OSTI)

    Cole, R.L.; Demirgian, J.C.; Allen, J.W.

    1987-09-01

    A mixture of 35 mole percent (mol %) 2-methylpyridine and 65 mol % water was tested at 575, 625, and 675/degree/F in a dynamic loop. Samples of the degraded fluid were chemically analyzed to determine the identities of major degradation products and the quantity of degradation. Computed degradation rates were found to be higher than those for Fluorinol 85 or toluene. For this reason (and other reasons, related to fluid handling), other fluids are recommended as the first choice for service in organic Rankine-cycle systems in preference to 2-methylpyridine/water. 7 refs., 39 figs., 39 tabs.

  18. Pervaporation separation of ethanol-water mixtures using polyethylenimine composite membranes

    DOE Patents [OSTI]

    Neidlinger, Hermann H.; Schissel, Paul O.; Orth, Richard A.

    1987-01-01

    Synthetic, organic, polymeric membranes were prepared from polyethylenimine for use with pervaporation apparatus in the separation of ethanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanate solution, after which the prepared membrane was heat-cured. The resulting membrane structures showed high selectivity in permeating ethanol or water over a wide range of feed concentrations.

  19. Molecular Characterization of Organosulfates in Organic Aerosols from Shanghai and Los Angeles Urban Areas by Nanospray-Desorption Electrospray Ionization High-Resolution Mass Spectrometry

    SciTech Connect (OSTI)

    Tao, Shikang; Lu, Xiaohui; Levac, Nicole A.; Bateman, Adam P.; Nguyen, Tran B.; Bones, David L.; Nizkorodov, Sergey; Laskin, Julia; Laskin, Alexander; Yang, Xin

    2014-08-21

    Aerosol samples collected in the urban areas of Shanghai and Los Angeles were analyzed by nanospray-desorption electrospray ionization mass spectrometry (nano-DESI MS) with high mass resolution (m/?m=100,000). Solvent mixtures of acetonitrile/water and acetonitrile/toluene were used to extract and ionize polar and non-polar compounds, respectively. A diverse mixture of oxygenated hydrocarbons, organosulfates, organonitrates, and organics with reduced nitrogen were detected in the Los Angeles sample. Majority of the organics in the Shanghai sample were detected as organosulfates. The dominant organosulfates in the two samples have distinctly different molecular characteristics. Specifically, organosulfates in the Los Angeles sample were dominated by isoprene- or monoterpene-derived products, while organosulfates of yet unknown origin in the Shanghai sample had distinctive characteristics of long aliphatic carbon chains and low degree of oxidation and unsaturation. The use of acetonitrile/toluene solvent facilitated identification of this type of organosulfates, suggesting they could be missed in previous studies relying on sample extraction using common polar solvents. The high molecular weight and low degree of unsaturation and oxidization of the organosulfates detected in the Shanghai sample suggest that they may act as surfactants, and plausibly affect the surface tension and hygroscopicity of the atmospheric particulate matter. We propose that direct esterification of carbonyl or hydroxyl compounds by sulfates or sulfuric acid in liquid phase could be the formation pathway of these special organosulfates. Long-chain alkanes from vehicle emissions might be their precursors.

  20. Synthesis of flower-like Boehmite (AlOOH) via a simple solvothermal process without surfactant

    SciTech Connect (OSTI)

    Li, Guangci; Liu, Yunqi; Liu, Di; Liu, Lihua; Liu, Chenguang

    2010-10-15

    Boehmite (AlOOH) with hierarchical flower-like structures was synthesized by the solvothermal reaction of AlCl{sub 3}.6H{sub 2}O in the presence of ethanol and toluene at 200 {sup o}C for 24 h. The product was characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that boehmite with flower-like nanostructures, which aggregated together by the weak hydrogen bonds, was formed through dissolution-deposition process of boehmite microcrystals and the toluene has a great effect on the morphology of product in the reaction system. Meanwhile, the {gamma}-Al{sub 2}O{sub 3} was also obtained by calcination of above product at 500 {sup o}C for 2 h, and the flower-like morphology kept no change. The surface area of {gamma}-Al{sub 2}O{sub 3} powder was determined to be 166.8 m{sup 2}/g by N{sub 2} adsorption measurement. The possible formation mechanism of flower-like boehmite nanostructures was proposed and discussed.

  1. Comparison between continuous stirred tank reactor extractor and soxhlet extractor for extraction of El-Lajjun oil shale

    SciTech Connect (OSTI)

    Anabtawi, M.Z. [Univ. of Bahrain, Isa Town (Bahrain)

    1996-02-01

    Extraction on El-Lajjun oil shale in a continuous stirred tank reactor extractor (CSTRE) and a Soxhlet extractor was carried out using toluene and chloroform as solvents. Solvents were recovered using two distillation stages, a simple distillation followed by a fractional distillation. Gas chromotography was used to test for the existence of trapped solvent in the yield. It was found that extraction using a CSTRE gave a 12% increase in yield on average compared with the Soxhlet extractor, and an optimum shale size of 1.0mm offered a better yield and solvent recovery for both techniques. It was also found that an optimum ratio of solvent to oil shale of 2:1 gave the best oil yield. The Soxhlet extractor was found to offer an extraction rate of 1 hour to complete extraction compared with 4 hours in a CSTRE. The yield in a CSTRE was found to increase on increase of stirring. When extraction was carried out at the boiling point of the solvents in a CSTRE, the yield was found to increase by 30% on average compared to that of extraction when the solvent was at room temperature. When toluene was used for extraction, the average amount of bitumen extracted was 0.032 g/g of oil shale and 76.4% of the solvent recovered, compared with 0.037 g/g of oil shale and 84.1% of the solvent recovered using a Soxhlet extractor.

  2. Anaerobic metabolism of nitroaromatic compounds by sulfate-reducing and methanogenic bacteria

    SciTech Connect (OSTI)

    Boopathy, R.; Kulpa, C.F.

    1994-06-01

    Ecological observations suggest that sulfate-reducing and methanogenic bacteria might metabolize nitroaromatic compounds under anaerobic conditions if appropriate electron donors and electron acceptors are present in the environment, but this ability had not been demonstrated until recently. Most studies on the microbial metabolism of nitroaromatic compounds used aerobic microorganisms. In most cases no mineralization of nitroaromatics occurs, and only superficial modifications of the structures are reported. However, under anaerobic sulfate-reducing conditions, the nitroaromatic compounds reportedly undergo a series of reductions with the formation of amino compounds. For example, trinitrotoluene under sulfate-reducing conditions is reduced to triaminotoluene by the enzyme nitrite reductase, which is commonly found in many Desulfovibrio spp. The removal of ammonia from triaminotoluene is achieved by reductive deamination catalyzed by the enzyme reductive deaminase, with the production of ammonia and toluene. Some sulfate reducers can metabolize toluene to CO{sub 2}. Similar metabolic processes could be applied to other nitroaromatic compounds like nitrobenzene, nitrobenzoic acids, nitrophenols, and aniline. Many methanogenic bacteria can reduce nitroaromatic compounds to amino compounds. In this paper we review the anaerobic metabolic processes of nitroaromatic compounds under sulfate-reducing And methanogenic conditions.

  3. Chemical Characterization of Crude Petroleum Using Nanospray Desorption Electrospray Ionization Coupled with High-Resolution Mass Spectrometry

    SciTech Connect (OSTI)

    Eckert, Peter A.; Roach, Patrick J.; Laskin, Alexander; Laskin, Julia

    2012-02-07

    Nanospray desorption electrospray ionization (nano-DESI) combined with high-resolution mass spectrometry was used for the first time for the analysis of liquid petroleum crude oil samples. The analysis was performed in both positive and negative ionization modes using three solvents one of which (acetonitrile/toluene mixture) is commonly used in petroleomics studies while two other polar solvents (acetonitrile/water and methanol/water mixtures) are generally not compatible with petroleum characterization using mass spectrometry. The results demonstrate that nano-DESI analysis efficiently ionizes petroleum constituents soluble in a particular solvent. When acetonitrile/toluene is used as a solvent, nano-DESI generates electrospray-like spectra. In contrast, strikingly different spectra were obtained using acetonitrile/water and methanol/water. Comparison with the literature data indicates that these solvents selectively extract water-soluble constituents of the crude oil. Water-soluble compounds are predominantly observed as sodium adducts in nano-DESI spectra indicating that addition of sodium to the solvent may be a viable approach for efficient ionization of water-soluble crude oil constituents. Nano-DESI enables rapid screening of different classes of compounds in crude oil samples using solvents that are rarely used for petroleum characterization.

  4. Molecular accessibility in solvent swelled coals. Quarterly report, [April--June 1993

    SciTech Connect (OSTI)

    Kispert, L.D.

    1993-08-01

    The effect of weathering (oxidation and dehydration upon exposure to air) on the molecular accessibility of potential catalysts was studied by the EPR spin probe technique. Fresh samples of all 8 APCS coals were exposed to air for periods up to 36 days. Weathering produced significant effects on the retention of spin probes in most of the APCS coals under 91 % carbon (dmmf). It was determined that the lower ranked coal (Beulah Zap and Wyodak) under went a structural collapse which precluded retention of even spin probe VIII. However, medium ranked coals exhibited improved retention upon weathering when swelled in toluene. Swelling with pyridine opened up small pores for 81--86% carbon which is not observed for swelling with toluene. Changes in coal structure were successfully followed by the EPR spin probe method. A detailed analysis of the data collected from the swelling of coals oxidized in a moisture free environment was completed to differentiate between weathering and oxidation. Eight vacuum dried APCS coals were oxidized in an enclosed, pure oxygen, moisture free environment, and the effects of oxidation alone on coal structure were studied by the intercalation of EPR spin probes. The data shows a factor of 5 increase in spin probe retention for some coals oxidized in O{sub 2} versus air., suggesting a large increase in oxidized material. Particular care was taken during the swelling procedures to avoid exposure of the coal samples to air or moisture. EPR spectra were then obtained for these 300 samples.

  5. Vapochromic LED

    DOE Patents [OSTI]

    Kunugi, Yoshihito; Mann, Kent R.; Miller, Larry L.; Exstrom, Christopher L.

    2003-06-17

    A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (.lambda..sub.max =545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal. The sensor comprises (a) a first electrode; (b) a hole transport layer formed on the first electrode; (c) a sensing/emitting layer formed on the hole transport layer, the sensing/emitting layer comprising a material that changes color upon exposure to the analyte vapors; (d) an electron conductor layer formed on the sensing layer; and (e) a second electrode formed on the electron conductor layer. The hole transport layer emits light at a shorter wavelength than the sensing/emitting layer and at least the first electrode comprises an optically transparent material.

  6. Vapochromic LED

    DOE Patents [OSTI]

    Kunugi, Yoshihito; Mann, Kent R.; Miller, Larry L.; Exstrom, Christopher L.

    2002-01-15

    A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (.mu..sub.max =545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal. The sensor comprises (a) a first electrode; (b) a hole transport layer formed on the first electrode; (c) a sensing/emitting layer formed on the hole transport layer, the sensing/emitting layer comprising a material that changes color upon exposure to the analyte vapors; (d) an electron conductor layer formed on the sensing layer; and (e) a second electrode formed on the electron conductor layer. The hole transport layer emits light at a shorter wavelength than the sensing/emitting layer and at least the first electrode comprises an optically transparent material.

  7. Henry's law constants for paint solvents and their implications on volatile organic compound emissions from automotive painting

    SciTech Connect (OSTI)

    Kim, B.R.; Kalis, E.M.; DeWulf, T.; Andrews, K.M.

    2000-02-01

    This paper describes experimental results of equilibrium partitioning of several significant paint solvents and formaldehyde between air and water to quantify the potential for capturing and retaining the constituents in spraybooth scrubber water during automotive painting. The compounds studied are toluene, n-butanol, methyl ethyl ketone methyl propyl ketone, methyl isobutyl ketone, methyl amyl ketone, butyl cellosolve, butyl cellosolve acetate, butyl carbitol, and n-methyl-2-pyrrolidinone. A set of field data collected at a Ford Motor Company assembly plant was also analyzed to determine whether data were consistent with the equilibrium phenomenon. The primary findings include: (a) There were more than six orders of magnitude difference in the Henry's law constants among the solvents studied. A solvent with a smaller constant is less easily stripped from water. The Henry's law constants decrease in the following order: toluene and xylenes > methyl ethyl ketone > n-butanol > butyl cellosolve acetate > butyl cellosolve > formaldehyde > butyl carbitol > n-methyl-2-pyrrolidinone. (b) Field data showed accumulation of n-methyl-2-pyrrolidinone and stable concentrations of butyl carbitol, butyl cellosolve, and n-butanol in the paint-sludge pit water during a 2-month period. Stable concentrations indicate a continuous, balanced capture and stripping of the solvents. Data were consistent with measured Henry's law constants. (c) The low Henry's law constant for formaldehyde is the result of the fact that it is hydrated when dissolved in water.

  8. Modeling of autoignition and NO sensitization for the oxidation of IC engine surrogate fuels

    SciTech Connect (OSTI)

    Anderlohr, J.M. |; Bounaceur, R.; Battin-Leclerc, F.; Pires Da Cruz, A.

    2009-02-15

    This paper presents an approach for modeling with one single kinetic mechanism the chemistry of the autoignition and combustion processes inside an internal combustion engine, as well as the chemical kinetics governing the postoxidation of unburned hydrocarbons in engine exhaust gases. Therefore a new kinetic model was developed, valid over a wide range of temperatures including the negative temperature coefficient regime. The model simulates the autoignition and the oxidation of engine surrogate fuels composed of n-heptane, iso-octane, and toluene, which are sensitized by the presence of nitric oxides. The new model was obtained from previously published mechanisms for the oxidation of alkanes and toluene where the coupling reactions describing interactions between hydrocarbons and NO{sub x} were added. The mechanism was validated against a wide range of experimental data obtained in jet-stirred reactors, rapid compression machines, shock tubes, and homogeneous charge compression ignition engines. Flow rate and sensitivity analysis were performed in order to explain the low temperature chemical kinetics, especially the impact of NO{sub x} on hydrocarbon oxidation. (author)

  9. Electroless preparation and characterization of Ni-B nanoparticles supported on multi-walled carbon nanotubes and their catalytic activity towards hydrogenation of styrene

    SciTech Connect (OSTI)

    Liu, Zheng; Li, Zhilin; Institute of Carbon Fibers and Composites, Beijing University of Chemical Technology, Beijing 100029 ; Wang, Feng; Institute of Carbon Fibers and Composites, Beijing University of Chemical Technology, Beijing 100029 ; Liu, Jingjun; Ji, Jing; Institute of Carbon Fibers and Composites, Beijing University of Chemical Technology, Beijing 100029 ; Park, Ki Chul; Endo, Morinobu

    2012-02-15

    Graphical abstract: The MWCNT/Ni-B catalyst has been successfully prepared by an electroless deposition process. The Ni-B nanoparticles on the supporter are amorphous and are well-distributed. The catalytic conversion towards hydrogenation of styrene shows excellent catalytic activity of the obtained materials. Highlights: Black-Right-Pointing-Pointer A two-step treatment of MWCNTs enabled the homogeneous growth of Ni-B nanoparticles. Black-Right-Pointing-Pointer Ni-B nanoparticles were amorphous with an average size of 60 nm. Black-Right-Pointing-Pointer There were electron transfer between Ni and B. Black-Right-Pointing-Pointer The catalyst had excellent catalytic activity towards hydrogenation of styrene. -- Abstract: Nickel-boron (Ni-B) nanoparticles supported on multi-walled carbon nanotubes (MWCNTs) were successfully synthesized through an electroless deposition process using the plating bath with sodium borohydride as a reducing agent. The structural and morphological analyses using field-emission scanning electron microscopy, X-ray diffractometry and high-resolution transmission electron microscopy have shown that the Ni-B nanoparticles deposited on the sidewalls of MWCNTs are fine spheres comprised of amorphous structure with the morphologically unique fine-structure like flowers, and homogenously dispersed with a narrow particle size distribution centered at around 60 nm diameter. The catalytic activity of MWCNT/Ni-B nanoparticles was evaluated with respect to hydrogenation of styrene. The hydrogenation catalyzed by MWCNT-supported Ni-B nanoparticles has been found to make styrene selectively converted into ethylbenzene. The highest conversion reaches 99.8% under proper reaction conditions, which demonstrates the high catalytic activity of MWCNT/Ni-B nanoparticles.

  10. Flash hydropyrolysis and methanolysis of biomass with hydrogen and methane

    SciTech Connect (OSTI)

    Steinberg, M.

    1985-04-01

    The process chemistry of the flash pyrolysis of biomass (wood) with the reactive gases, H/sub 2/ and CH/sub 4/ and with the non-reactive gases He and N/sub 2/ is being determined in a 1 in. downflow tubular reactor at pressures from 20 to 1000 psi and temperatures from 600 to 1000/sup 0/C. With hydrogen, flash hydropyrolysis leads to high yields of methane and CO which can be used for SNG and methanol fuel production. With methane, flash methanolysis leads to high yields of ethylene, benzene and CO which can be used for the production of valuable chemical feedstocks and methanol transportation fuel. At reactor conditions of 50 psi and 1000/sup 0/C and approximately 1 sec residence time, the yields based on pine wood carbon conversion are up to 30% for ethylene, 25% for benzene, and 45% for CO, indicating that over 90% of the carbon in pine is converted to valuable products. Pine wood produces higher yields of hydrocarbon products than Douglas fir wood; the yield of ethylene is 2.3 times higher with methane than with helium or nitrogen, and for pine, the ratio is 7.5 times higher. The mechanism appears to be a free radical reaction between CH/sub 4/ and the pyrolyzed wood. There appears to be no net production or consumption of methane. A preliminary process design and analysis indicates an economically competitive system for the production of ethylene, benzene and methanol based on the methanolysis of wood. 8 refs., 18 figs., 1 tab.

  11. Flash pyrolysis of biomass with reactive and non-reactive gases

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.T.; Sundaram, M.S.

    1985-03-01

    The process chemistry of the flash pyrolysis of biomass (wood) with the reactive gases, H/sub 2/ and CH/sub 4/ and with the non-reactive gases He and N/sub 2/ is being determined in a 1'' downflow tubular reactor at pressures from 20 to 1000 psi and temperatures from 600 to 1000/sup 0/C. With hydrogen, flash hydropyrolysis leads to high yields of methane and CO which can be used for SNG and methanol fuel production. With methane, flash methanolysis leads to high yields of ethylene, benzene and CO which can be used for the production of valuable chemical feedstocks and methanol transportation fuel. At reactor conditions of 50 psi and 1000/sup 0/C and approximately 1 sec residence time, the yields based on pine wood carbon conversion are up to 30% for ethylene, 25% for benzene, and 45% for CO, indicating that over 90% of the carbon in pine is converted to valuable products. Pine wood produces higher yields of hydrocarbon products than Douglas fir wood; the yield of ethylene is 2.3 times higher with methane than with helium or nitrogen, and for pine, the ratio is 7.5 times higher. The mechanism appears to be a free radical reaction between CH/sub 4/ and the pyrolyzed wood. There appears to be no net production or consumption of methane. A preliminary process design and analysis indicates an economically competitive system for the production of ethylene, benzene and methanol based on the methanolysis of wood. 8 refs., 18 figs., 1 tab.

  12. Impact of California Phase 2 reformulated gasoline on atmospheric reactivity of exhaust and evaporative emissions

    SciTech Connect (OSTI)

    Kirchstetter, T.W.; Singer, B.C.; Harley, R.A.; Kendall, G.R.; Traverse, M.

    1997-12-31

    Phase 2 of California`s reformulated gasoline (RFG) program took effect statewide in the first half of 1996. Changes to gasoline composition required by Phase 2 specifications included: lower vapor pressure; lower olefin, aromatic, benzene, and sulfur content; lower T50 and T90; and a minimum oxygen content. In this paper, impacts of Phase 2 RFG on the atmospheric reactivity of motor vehicle exhaust and evaporative emissions are described. Volatile organic compounds in motor vehicle exhaust were measured at the Caldecott tunnel in summer 1995 and 1996. Aggregate emissions of greater than 8000 vehicles were measured each day. Regular and premium grade gasoline samples were collected from service stations in Berkeley concurrently with tunnel measurements both summers. Liquid gasoline samples and their headspace vapors were analyzed to determine detailed chemical composition. Normalized reactivity was calculated for exhaust and evaporative emissions by applying maximum incremental reactivity values to the detailed speciation profiles. Results indicate that the composition of gasoline in 1996 differed markedly from that of 1995. Changes in liquid gasoline composition led to corresponding changes in the speciation of vehicle exhaust and of gasoline headspace vapors. Benzene concentration in liquid gasoline decreased from 2.0 to 0.6 wt%, which contributed to a 70 and 37% reduction in benzene weight fraction in headspace vapors and vehicle exhaust, respectively. Addition of MTBE and reduction of olefins and aromatics in gasoline led to significant reductions in the atmospheric reactivity of unburned gasoline and gasoline headspace vapors. The normalized reactivity of liquid gasoline and headspace vapors decreased by 23 and 19%, respectively, between 1995 and 1996. The normalized reactivity of non-methane organic compounds in vehicle exhaust decreased by about 8%, but the uncertainty in this change was large.

  13. Coal liquefaction with preasphaltene recycle

    DOE Patents [OSTI]

    Weimer, Robert F.; Miller, Robert N.

    1986-01-01

    A coal liquefaction system is disclosed with a novel preasphaltene recycle from a supercritical extraction unit to the slurry mix tank wherein the recycle stream contains at least 90% preasphaltenes (benzene insoluble, pyridine soluble organics) with other residual materials such as unconverted coal and ash. This subject process results in the production of asphaltene materials which can be subjected to hydrotreating to acquire a substitute for No. 6 fuel oil. The preasphaltene-predominant recycle reduces the hydrogen consumption for a process where asphaltene material is being sought.

  14. Preconversion catalytic deoxygenation of phenolic functional groups. Quarterly technical progress report, January 1, 1992--March 31, 1992

    SciTech Connect (OSTI)

    Kubiak, C.P.

    1992-08-01

    The deoxygenation of phenols is a conceptually simple, but unusually difficult chemical transformation to achieve. The phenolic C-O bond energy of 103 kcal/mol is as strong as a benzene C-H bond and over a 10 kcal/mol stronger than the C-O bonds of methanol and ethanol. The consequence of this is that the hydrogenation/deoxygenation methods in current use require severe conditions and give low selectivities. The ongoing research described herein is based on the unprecedented, but thermodynamically promising, use of carbon monoxide as the oxygen atom acceptor for the catalytic deoxygenation of phenols.

  15. Measurement of the quantum efficiency of TMAE and TEA from threshold to 120 nm

    SciTech Connect (OSTI)

    Holroyd, R.A.; Preses, J.M.; Woody, C.L.; Johnson, R.A.

    1986-01-01

    Several existing and planned high energy physics experiments incorporate detectors which use either TMAE (tetrakis-dimethylaminoethylene) or TEA (triethylamine) as their photosensitive agent. Understanding the operation of these devices requires knowledge of the absolute photoionization quantum efficiencies and absorption lengths of TMAE and TEA. In an experiment performed at the National Synchrotron Light source at Brookhaven National Laboratory, we have measured these parameters from 120 nm to 280 nm. The quantum efficiencies were normalized to the known photoionization yields of benzene and cis-2-butene. The results of these measurements and details of the experiment are presented in this paper.

  16. Liquid electrode

    DOE Patents [OSTI]

    Ekechukwu, A.A.

    1994-07-05

    A dropping electrolyte electrode is described for use in electrochemical analysis of non-polar sample solutions, such as benzene or cyclohexane. The liquid electrode, preferably an aqueous salt solution immiscible in the sample solution, is introduced into the solution in dropwise fashion from a capillary. The electrolyte is introduced at a known rate, thus, the droplets each have the same volume and surface area. The electrode is used in making standard electrochemical measurements in order to determine properties of non-polar sample solutions. 2 figures.

  17. Process for the production of ethylene and other hydrocarbons from coal

    DOE Patents [OSTI]

    Steinberg, Meyer; Fallon, Peter

    1986-01-01

    A process for the production of economically significant amounts of ethyl and other hydrocarbon compounds, such as benzene, from coal is disclosed wherein coal is reacted with methane at a temperature in the approximate range of 500.degree. C. to 1100.degree. C. at a partial pressure less than about 200 psig for a period of less than 10 seconds. Ethylene and other hydrocarbon compounds may be separated from the product stream so produced, and the methane recycled for further production of ethylene. In another embodiment, other compounds produced, such as by-product tars, may be burned to heat the recycled methane.

  18. Formation of carbon deposits from coal in an arc plasma

    SciTech Connect (OSTI)

    Wang, B.; Tian, Y.; Zhang, Y.; Zhu, S.; Lu, Y.; Zhang, Y.; Xie, K.

    2007-07-01

    The issue of deposited carbon (DC) on a reactor wall during the production of acetylene by the coal/arc plasma process is a potential obstacle for the industrialization process. The formation mechanism of DC is very difficult to reveal because the high complexity of coal and the volatile matter. Combining with quenching technique, the methane, liquid petroleum gas and benzene were employed as the model materials to roughly act as the light gas, chain and aromatic subcomponents of volatile matter, and then the reasonable formation mechanism of DC was subtly speculated accordingly.

  19. Use of 2,5-dimethyl-2,5-hexane diamine as a curing agent for epoxy resins

    DOE Patents [OSTI]

    Rinde, James A. [Livermore, CA; Newey, Herbert A. [Lafayette, CA

    1981-02-24

    Primary diamines of the formula ##STR1## wherein R is a straight chain saturated hydrocarbon of 2 to 4 carbons, a disubstituted benzene ring, or disubstituted dibenzo methane for use as a curing agent for epoxy resins. These curing agents can be used to form epoxy resin mixtures useful in filament winding and pre-impregnated fiber molding and in formulating film adhesives, powder coatings and molding powders. The epoxy mixtures form for such uses as room temperature non-reacting, intermediate stable state which has a latent cross-linking capability.

  20. Use of 2,5-dimethyl-2,5-hexane diamine as a curing agent for epoxy resins

    DOE Patents [OSTI]

    Rinde, J.A.; Newey, H.A.

    1981-02-24

    Primary diamines are disclosed of the formula shown in a diagram wherein R is a straight chain saturated hydrocarbon of 2 to 4 carbons, a disubstituted benzene ring, or disubstituted dibenzomethane for use as a curing agent for epoxy resins. These curing agents can be used to form epoxy resin mixtures useful in filament winding and pre-impregnated fiber molding and in formulating film adhesives, powder coatings and molding powders. The epoxy mixtures form for such uses as room temperature non-reacting, intermediate stable state which has a latent cross-linking capability.

  1. Complex absorbing potential based Lorentzian fitting scheme and time dependent quantum transport

    SciTech Connect (OSTI)

    Xie, Hang Kwok, Yanho; Chen, GuanHua; Jiang, Feng; Zheng, Xiao

    2014-10-28

    Based on the complex absorbing potential (CAP) method, a Lorentzian expansion scheme is developed to express the self-energy. The CAP-based Lorentzian expansion of self-energy is employed to solve efficiently the Liouville-von Neumann equation of one-electron density matrix. The resulting method is applicable for both tight-binding and first-principles models and is used to simulate the transient currents through graphene nanoribbons and a benzene molecule sandwiched between two carbon-atom chains.

  2. A low energy electron microscopy study of the initial growth, structure, and thermal stability of 4,4{sup '}-biphenyldicarboxylic acid domains on Cu(001)

    SciTech Connect (OSTI)

    Khokhar, Fawad S.; Gastel, Raoul van; Schwarz, Daniel; Zandvliet, Harold J. W.; Poelsema, Bene

    2011-09-28

    The growth of 4,4{sup '}-biphenyldicarboxylic acid (BDA) on Cu(001) has been studied using low energy electron microscopy and selective area low energy electron diffraction. The emergence of large islands and hydrogen bonding to perpendicularly oriented, adjacent molecules is confirmed. The two benzene rings of adsorbed BDA are twisted along the molecular axis. Unconventional growth of the domains, followed by a second nucleation stage, is observed at room temperature. This unanticipated feature is attributed to the accumulation of stress in the islands. Ostwald ripening in the films and the decay of BDA domains at 448 K exhibits features that are consistent with diffusion limited behavior.

  3. An x-ray setup to investigate the atomic order of confined liquids in slit geometry

    SciTech Connect (OSTI)

    Lippmann, M.; Ehnes, A.; Seeck, O. H.

    2014-01-15

    A setup has been designed to investigate thin films of confined liquids with the use of X-ray scattering methods. The confinement is realized between the flat culets of a pair of diamonds by positioning and orienting the lower diamond with nanometer and micro radian accuracy. We routinely achieve gaps between 5 and 50 nm at culet diameters of 200 ?m. With this setup and a micro focused X-ray beam we have investigated the in-plane and the out-off-plane atomic order of benzene with atomic resolution.

  4. Monolayer-induced band shifts at Si(100) and Si(111) surfaces

    SciTech Connect (OSTI)

    Mäkinen, A. J. Kim, Chul-Soo; Kushto, G. P.

    2014-01-27

    We report our study of the interfacial electronic structure of Si(100) and Si(111) surfaces that have been chemically modified with various organic monolayers, including octadecene and two para-substituted benzene derivatives. X-ray photoelectron spectroscopy reveals an upward band shift, associated with the assembly of these organic monolayers on the Si substrates, that does not correlate with either the dipole moment or the electron withdrawing/donating character of the molecular moieties. This suggests that the nature and quality of the self-assembled monolayer and the intrinsic electronic structure of the semiconductor material define the interfacial electronic structure of the functionalized Si(100) and Si(111) surfaces.

  5. Recent progress in electron scattering from atoms and molecules

    SciTech Connect (OSTI)

    Brunger, M. J.; Buckman, S. J.; Sullivan, J. P.; Palihawadana, P.; Jones, D. B.; Chiari, L.; Pettifer, Z.; Silva, G. B. da; Lopes, M. C. A.; Duque, H. V.; Masin, Z.; Gorfinkiel, J. D.; Garcia, G.; Hoshino, M.; Tanaka, H.; Limão-Vieira, P.

    2014-03-05

    We present and discuss recent results, both experimental and theoretical (where possible), for electron impact excitation of the 3s[3/2 ]{sub 1} and 3s?[1/2 ]{sub 1} electronic states in neon, elastic electron scattering from the structurally similar molecules benzene, pyrazine, and 1,4-dioxane and excitation of the electronic states of the important bio-molecule analogue ?-tetrahydrofurfuryl alcohol. While comparison between theoretical and experimental results suggests that benchmarked cross sections for electron scattering from atoms is feasible in the near-term, significant further theoretical development for electron-molecule collisions, particularly in respect to discrete excitation processes, is still required.

  6. Phonon interference effects in molecular junctions

    SciTech Connect (OSTI)

    Markussen, Troels

    2013-12-28

    We study coherent phonon transport through organic, ?-conjugated molecules. Using first principles calculations and Green's function methods, we find that the phonon transmission function in cross-conjugated molecules, like meta-connected benzene, exhibits destructive quantum interference features very analogous to those observed theoretically and experimentally for electron transport in similar molecules. The destructive interference features observed in four different cross-conjugated molecules significantly reduce the thermal conductance with respect to linear conjugated analogues. Such control of the thermal conductance by chemical modifications could be important for thermoelectric applications of molecular junctions.

  7. Laboratory investigations of irradiated acetonitrile-containing ices on an interstellar dust analog

    SciTech Connect (OSTI)

    Abdulgalil, Ali G. M.; Marchione, Demian; Rosu-Finsen, Alexander; Collings, Mark P.; McCoustra, Martin R. S.

    2012-07-15

    Reflection-absorption infrared spectroscopy is used to study the impact of low-energy electron irradiation of acetonitrile-containing ices, under conditions close to those in the dense star-forming regions in the interstellar medium. Both the incident electron energy and the surface coverage were varied. The experiments reveal that solid acetonitrile is desorbed from its ultrathin solid films with a cross section of the order of 10{sup -17} cm{sup 2}. Evidence is presented for a significantly larger desorption cross section for acetonitrile molecules at the water-ice interface, similar to that previously observed for the benzene-water system.

  8. Photo-degradation of Lexan polycarbonate studied using positron lifetime spectroscopy

    SciTech Connect (OSTI)

    Hareesh, K.; Sanjeev, Ganesh; Pandey, A. K.; Meghala, D.; Ranganathaiah, C.

    2013-02-05

    The free volume properties of pristine and UV irradiated Lexan polycarbonate have been investigated using Positron Lifetime Spectroscopy (PLS). The decrease in o-Ps life time and free volume size of irradiated sample is attributed to free volume modification and formation of more stable free radicals. These free radicals are formed due to the breakage of C-O bonds in Lexan polycarbonate after irradiation. This is also supported by the decrease in the intensity of C-O bond after exposure to UV-radiation as studied from Fourier Transform Infrared (FTIR) spectroscopy and it also shows that benzene ring does not undergo any changes after irradiation.

  9. Aromatics oxidation and soot formation in flames

    SciTech Connect (OSTI)

    Howard, J.B.; Pope, C.J.; Shandross, R.A.; Yadav, T.

    1993-12-01

    This project is concerned with the kinetics and mechanisms of aromatics oxidation and soot and fullerenes formation in flames. The scope includes detailed measurements of profiles of stable and radical species concentrations in low-pressure one-dimensional premixed flames. Intermediate species identifications and mole fractions, fluxes, and net reaction rates calculated from the measured profiles are used to test postulated reaction mechanisms. Particular objectives are to identify and to determine or confirm rate constants for the main benzene oxidation reactions in flames, and to characterize fullerenes and their formation mechanisms and kinetics.

  10. Annual Report of Site Surveillance and Maintenance Activities at the Rocky Flats Site, Colorado Calendar Year 2015

    Office of Legacy Management (LM)

    57 4.0 References 8 CCR 1206-2. "Rules Pertaining to the Administration and Enforcement of the Colorado Noxious Weed Act," Code of Colorado Regulations. Adrian, L. and H. Gorisch, 2002." Microbial transformation of chlorinated benzenes under anaerobic conditions," in Research in Microbiology 153, pp. 131-137; Elsevier, February 14. Carter, R.W., and J. Davidian, 1968. General Procedure for Gaging Streams: U.S. Geological Survey Techniques of Water-Resources Investigations,

  11. Microsoft Word - S12421_2014 Annual Rpt.docx

    Office of Legacy Management (LM)

    445 4.0 References 8 CCR 1206-2. "Rules Pertaining to the Administration and Enforcement of the Colorado Noxious Weed Act," Code of Colorado Regulations. Adrian, L. and H. Gorisch, 2002." Microbial transformation of chlorinated benzenes under anaerobic conditions," in Research in Microbiology 153, pp. 131-137; Elsevier, February 14. Carter, R.W., and J. Davidian, 1968. General Procedure for Gaging Streams: U.S. Geological Survey Techniques of Water-Resources Investigations,

  12. On the formation and decomposition of C{sub 7}H{sub 8}.

    SciTech Connect (OSTI)

    Klippenstein, S. J.; Harding, L. B.; Georgievskii, Y.; Chemistry; SNL

    2007-01-01

    The kinetics of reactions on the C{sub 7}H{sub 8} surface were studied with state-of-the-art ab initio transition state theory (TST) and master equation methodologies. A priori predictions of the capture rate for C{sub 6}H{sub 5} + CH{sub 3} and for C{sub 7}H{sub 7} + H are obtained from direct variable reaction coordinate TST simulations. These simulations employ small basis set CASPT2 interaction energies coupled with one-dimensional reaction path corrections based on higher level simulations for related reactions. For the C{sub 7}H{sub 7} + H reaction, predictions are obtained for both the total rate and for the branching between toluene, o-isotoluene and p-isotoluene. A mapping of the low energy pathways for isomerization from these three C{sub 7}H{sub 8} isomers identifies a number of processes with barriers at or below the dissociation threshold. Nevertheless, at combustion temperatures the dissociation rates are predicted to exceed the isomerization rates, and it is reasonable to treat the kinetics of each isomer as a simple single well association/dissociation equilibrium. Master equation simulations yield predictions for the temperature and pressure dependence of each of the recombination and dissociation processes, as well as for the C{sub 7}H{sub 7} + H {yields} C{sub 6}H{sub 5} + CH{sub 3} bimolecular reaction. These simulations implement collisional energy transfer probabilities based on the work of Luther and co-workers. The theoretical predictions are found to be in satisfactory agreement with the available experimental data for the photodissociation of toluene, the temperature and pressure dependent dissociation of toluene, and the reaction of benzyl radical with H. For the C{sub 6}H{sub 5} + CH{sub 3} recombination, the theoretical predictions exceed the experimental measurements of Lin and coworkers by a factor of 2 or more for all temperatures.

  13. Partially-Premixed Flames in Internal Combustion Engines

    SciTech Connect (OSTI)

    Robert W. Pitz; Michael C. Drake; Todd D. Fansler; Volker Sick

    2003-11-05

    This was a joint university-industry research program funded by the Partnerships for the Academic-Industrial Research Program (PAIR). The research examined partially premixed flames in laboratory and internal combustion engine environments at Vanderbilt University, University of Michigan, and General Motors Research and Development. At Vanderbilt University, stretched and curved ''tubular'' premixed flames were measured in a unique optically accessible burner with laser-induced spontaneous Raman scattering. Comparisons of optically measured temperature and species concentration profiles to detailed transport, complex chemistry simulations showed good correspondence at low-stretch conditions in the tubular flame. However, there were significant discrepancies at high-stretch conditions near flame extinction. The tubular flame predictions were found to be very sensitive to the specific hydrogen-air chemical kinetic mechanism and four different mechanisms were compared. In addition, the thermo-diffusive properties of the deficient reactant, H2, strongly affected the tubular flame structure. The poor prediction near extinction is most likely due to deficiencies in the chemical kinetic mechanisms near extinction. At the University of Michigan, an optical direct-injected engine was built up for laser-induced fluorescence imaging experiments on mixing and combustion under stratified charge combustion conditions with the assistance of General Motors. Laser attenuation effects were characterized both experimentally and numerically to improve laser imaging during the initial phase of the gasoline-air mixture development. Toluene was added to the isooctane fuel to image the fuel-air equivalence ratio in an optically accessible direct-injected gasoline engine. Temperature effects on the toluene imaging of fuel-air equivalence ratio were characterized. For the first time, oxygen imaging was accomplished in an internal combustion engine by combination of two fluorescence trackers, toluene and 3-pentanone. With this method, oxygen, fuel and equivalence ratio were measured in the cylinder. At General Motors, graduate students from the University of Michigan and Vanderbilt University worked with GM researchers to develop high-speed imaging methods for optically accessible direct-injection engines. Spark-emission spectroscopy was combined with high-speed spectrally-resolved combustion imaging in a direct-injected engine.

  14. Catalytic production of metal carbonyls from metal oxides

    DOE Patents [OSTI]

    Sapienza, Richard S.; Slegeir, William A.; Foran, Michael T.

    1984-01-01

    This invention relates to the formation of metal carbonyls from metal oxides and specially the formation of molybdenum carbonyl and iron carbonyl from their respective oxides. Copper is used here in admixed form or used in chemically combined form as copper molybdate. The copper/metal oxide combination or combined copper is utilized with a solvent, such as toluene and subjected to carbon monoxide pressure of 25 atmospheres or greater at about 150.degree.-260.degree. C. The reducing metal copper is employed in catalytic concentrations or combined concentrations as CuMoO.sub.4 and both hydrogen and water present serve as promoters. It has been found that the yields by this process have been salutary and that additionally the catalytic metal may be reused in the process to good effect.

  15. Catalytic production of metal carbonyls from metal oxides

    DOE Patents [OSTI]

    Sapienza, R.S.; Slegeir, W.A.; Foran, M.T.

    1984-01-06

    This invention relates to the formation of metal carbonyls from metal oxides and specially the formation of molybdenum carbonyl and iron carbonyl from their respective oxides. Copper is used here in admixed form or used in chemically combined form as copper molybdate. The copper/metal oxide combination or combined copper is utilized with a solvent, such as toluene and subjected to carbon monoxide pressure of 25 atmospheres or greater at about 150 to 260/sup 0/C. The reducing metal copper is employed in catalytic concentrations or combined concentrations as CuMoO/sub 4/ and both hydrogen and water present serve as promoters. It has been found that the yields by this process have been salutary and that additionally the catalytic metal may be reused in the process to good effect. 3 tables.

  16. METHOD FOR PRODUCING CEMENTED CARBIDE ARTICLES

    DOE Patents [OSTI]

    Onstott, E.I.; Cremer, G.D.

    1959-07-14

    A method is described for making molded materials of intricate shape where the materials consist of mixtures of one or more hard metal carbides or oxides and matrix metals or binder metals thereof. In one embodiment of the invention 90% of finely comminuted tungsten carbide powder together with finely comminuted cobalt bonding agent is incorporated at 60 deg C into a slurry with methyl alcohol containing 1.5% paraffin, 3% camphor, 3.5% naphthalene, and 1.8% toluene. The compact is formed by the steps of placing the slurry in a mold at least one surface of which is porous to the fluid organic system, compacting the slurry, removing a portion of the mold from contact with the formed object and heating the formed object to remove the remaining organic matter and to sinter the compact.

  17. Application of emulsifiers in the manufacture of cast boosters and related products

    SciTech Connect (OSTI)

    Joginadham, C.; Shankar, P.S.; Gupta, A.N.

    1996-12-01

    Cast boosters made with pentaerythritol tetranitrate (PETN) and trinitro toluene (TNT) give high velocities of detonation and are sensitive to initiation even under high pressures. However, the manufacture of the same involves heating of TNT to its melting temperature and mixing of dry PETN in it. In the present work, wet PETN, TNT and water soluble nitrate salts were used for the manufacture of the boosters. The nitrate salt solution formed with the excess water available in wet PETN was emulsified with the aid of emulsifiers. The velocities of detonation of boosters with various percentages of water were determined. The data of explosive characters of these boosters were compared with normal pentolite cast boosters.

  18. Method to prepare Semtex

    SciTech Connect (OSTI)

    Alcaraz, A; Dougan, A

    2006-11-26

    This procedure requires the binder and uncoated RDX be prepared in separate steps, see Figure 1: (1) The binder and dye are mixed by agitation with a water-insoluble organic solvent (e.g., toluene), I; (2) The RDX/PETN is agitated thoroughly with water, II; (3) The binder solution I is added to the RDX/water mixture at II with thorough mixing to form a slurry III; (4) In the next step the solvent is distilled off at IV leaving resulting granules; (5) The next step is followed by filtration at V, which may be done by vacuum; (6) The composition is then dried at VI to a dough-like consistency.

  19. Engine Materials Compatability with Alternative Fuels

    SciTech Connect (OSTI)

    Pawel, Steve; Moore, D.

    2013-04-05

    The compatibility of aluminum and aluminum alloys with synthetic fuel blends comprised of ethanol and reference fuel C (a 50/50 mix of toluene and iso-octane) was examined as a function of water content and temperature. Commercially pure wrought aluminum and several cast aluminum alloys were observed to be similarly susceptible to substantial corrosion in dry (< 50 ppm water) ethanol. Corrosion rates of all the aluminum materials examined were accelerated by increased temperature and ethanol content in the fuel mixture, but inhibited by increased water content. Pretreatments designed to stabilize passive films on aluminum increased the incubation time for onset of corrosion, suggesting film stability is a significant factor in the mechanism of corrosion.

  20. Engine Materials Compatibility with Alternate Fuels

    SciTech Connect (OSTI)

    Thomson, Jeffery K; Pawel, Steven J; Wilson, Dane F

    2013-05-01

    The compatibility of aluminum and aluminum alloys with synthetic fuel blends comprised of ethanol and reference fuel C (a 50/50 mix of toluene and iso-octane) was examined as a function of water content and temperature. Commercially pure wrought aluminum and several cast aluminum alloys were observed to be similarly susceptible to substantial corrosion in dry (< 50 ppm water) ethanol. Corrosion rates of all the aluminum materials examined were accelerated by increased temperature and ethanol content in the fuel mixture, but inhibited by increased water content. Pretreatments designed to stabilize passive films on aluminum increased the incubation time for onset of corrosion, suggesting film stability is a significant factor in the mechanism of corrosion.

  1. Thermally activated delayed fluorescence from {sup 3}n?* to {sup 1}n?* up-conversion and its application to organic light-emitting diodes

    SciTech Connect (OSTI)

    Li, Jie; Zhang, Qisheng; Nomura, Hiroko [Department of Chemistry and Biochemistry, and Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan); Miyazaki, Hiroshi [Department of Chemistry and Biochemistry, and Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan); Functional Materials Laboratory, Nippon Steel and Sumikin Chemical Co., Ltd, 46–80 Nakabaru, Sakinohama, Tobata, Kitakyushu, Fukuoka 804–8503 (Japan); Adachi, Chihaya, E-mail: adachi@cstf.kyushu-u.ac.jp [Department of Chemistry and Biochemistry, and Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan); International Institute for Carbon Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Motooka, Nishi, Fukuoka 819-0395 (Japan)

    2014-07-07

    Intense n?* fluorescence from a nitrogen-rich heterocyclic compound, 2,5,8-tris(4-fluoro-3-methylphenyl)-1,3,4,6,7,9,9b-heptaazaphenalene (HAP-3MF), is demonstrated. The overlap-forbidden nature of the n?* transition and the higher energy of the {sup 3}??* state than the {sup 3}n?* one lead to a small energy difference between the lowest singlet (S{sub 1}) and triplet (T{sub 1}) excited states of HAP-3MF. Green-emitting HAP-3MF has a moderate photoluminescence quantum yield of 0.26 in both toluene and doped film. However, an organic light-emitting diode containing HAP-3MF achieved a high external quantum efficiency of 6.0%, indicating that HAP-3MF harvests singlet excitons through a thermally activated T{sub 1} ? S{sub 1} pathway in the electroluminescent process.

  2. Comparison of advanced distillation control methods. Third annual report

    SciTech Connect (OSTI)

    Riggs, J.B.

    1997-07-01

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to study the issue of configuration selection for diagonal PI dual composition controls, feedforward from a feed composition analyzer, and decouplers. Auto Tune Variation (ATV) identification with on-line detuning for setpoint changes was used for tuning the diagonal proportional integral (PI) composition controls. In addition, robustness tests were conducted by inducting reboiler duty upsets. For single composition control, the (L, V) configuration was found to be best. For dual composition control, the optimum configuration changes from one column to another. Moreover, the use of analysis tools, such as RGA, appears to be of little value in identifying the optimum configuration for dual composition control. Using feedforward from a feed composition analyzer and using decouplers are shown to offer significant advantages for certain specific cases.

  3. Optical Properties of CdSe Nanoparticle Assemblies

    SciTech Connect (OSTI)

    Huser, T; Gerion, D; Zaitseva, N; Krol, D M; Leon, F R

    2003-11-24

    We report on three-dimensional fluorescence imaging of micron-size faceted crystals precipitated from solutions of CdSe nanocrystals. Such crystals have previously been suggested to be superlattices of CdSe quantum dots [1,2]. Possible applications for these materials include their use in optical and optoelectronic devices. The micron-size crystals were grown by slow evaporation from toluene solutions of CdSe nanocrystals in the range of 3-6 nm, produced by traditional wet-chemistry techniques. By using a confocal microscope with laser illumination, three-dimensional raster-scanning and synchronized hyper-spectral detection, we have generated spatial profiles of the fluorescence emission intensity and spectrum. The fluorescence data of the micro-crystals were compared with spectra of individual nanocrystals obtained from the same solution. The results do not support the assertion that these microcrystals consist of CdSe superlattices.

  4. Detailed Kinetic Modeling of Gasoline Surrogate Mixtures

    SciTech Connect (OSTI)

    Mehl, M; Curran, H J; Pitz, W J; Westbrook, C K

    2009-03-09

    Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. It is generally agreed that their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. In this work, a recently revised version of the kinetic model by the authors is used to analyze the combustion behavior of several components relevant to gasoline surrogate formulation. Particular attention is devoted to linear and branched saturated hydrocarbons (PRF mixtures), olefins (1-hexene) and aromatics (toluene). Model predictions for pure components, binary mixtures and multi-component gasoline surrogates are compared with recent experimental information collected in rapid compression machine, shock tube and jet stirred reactors covering a wide range of conditions pertinent to internal combustion engines. Simulation results are discussed focusing attention on the mixing effects of the fuel components.

  5. Kinetic Modeling of Gasoline Surrogate Components and Mixtures under Engine Conditions

    SciTech Connect (OSTI)

    Mehl, M; Pitz, W J; Westbrook, C K; Curran, H J

    2010-01-11

    Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. It is generally agreed that their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. In this work, an improved version of the kinetic model by the authors is used to analyze the combustion behavior of several components relevant to gasoline surrogate formulation. Particular attention is devoted to linear and branched saturated hydrocarbons (PRF mixtures), olefins (1-hexene) and aromatics (toluene). Model predictions for pure components, binary mixtures and multicomponent gasoline surrogates are compared with recent experimental information collected in rapid compression machine, shock tube and jet stirred reactors covering a wide range of conditions pertinent to internal combustion engines (3-50 atm, 650-1200K, stoichiometric fuel/air mixtures). Simulation results are discussed focusing attention on the mixing effects of the fuel components.

  6. Chemical kinetic modeling of component mixtures relevant to gasoline

    SciTech Connect (OSTI)

    Mehl, M; Curran, H J; Pitz, W J; Westbrook, C K

    2009-02-13

    Real fuels are complex mixtures of thousands of hydrocarbon compounds including linear and branched paraffins, naphthenes, olefins and aromatics. It is generally agreed that their behavior can be effectively reproduced by simpler fuel surrogates containing a limited number of components. In this work, a recently revised version of the kinetic model by the authors is used to analyze the combustion behavior of several components relevant to gasoline surrogate formulation. Particular attention is devoted to linear and branched saturated hydrocarbons (PRF mixtures), olefins (1-hexene) and aromatics (toluene). Model predictions for pure components, binary mixtures and multi-component gasoline surrogates are compared with recent experimental information collected in rapid compression machine, shock tube and jet stirred reactors covering a wide range of conditions pertinent to internal combustion engines. Simulation results are discussed focusing attention on the mixing effects of the fuel components.

  7. Innovative technology for expedited site remediation of extensive surface and subsurface contamination

    SciTech Connect (OSTI)

    Audibert, J.M.E.; Lew, L.R.

    1994-12-31

    Large scale surface and subsurface contamination resulted from numerous releases of feed stock, process streams, waste streams, and final product at a major chemical plant. Soil and groundwater was contaminated by numerous compounds including lead, tetraethyl lead, ethylene dibromide, ethylene dichloride, and toluene. The state administrative order dictated that the site be investigated fully, that remedial alternative be evaluated, and that the site be remediated within a year period. Because of the acute toxicity and extreme volatility of tetraethyl lead and other organic compounds present at the site and the short time frame ordered by the regulators, innovative approaches were needed to carry out the remediation while protecting plant workers, remediation workers, and the public.

  8. Health assessment for S-Area Landfill/Hooker, Niagara Falls, New York, Region 2. CERCLIS No. NYD000000001. Preliminary report

    SciTech Connect (OSTI)

    Not Available

    1989-06-01

    The S-Area Landfill is a National Priorities List site located in Niagara Falls, New York, that was operated from 1947 to 1975 by the Occidental Chemical Corporation (OCC). From 1947 to 1975, OCC is reported to have disposed of an estimated 19,000 tons of chlorobenzenes and approximately 17,000 tons of hexachlorocyclopentadiene. Other wastes disposed of at the site include organic phosphates, hexachlorobutadiene, trichlorophenols, and chlorinated toluenes. Environmental contamination from the S-Area exists on-site and off-site in soils and ground water. Further off-site contamination potentially exists in the Niagara River. The S-Area presents a potential public health threat to the consumers of the City of Niagara Falls drinking water and an incremental increase in contamination to fish in the Niagara River.

  9. Next generation extractants for separation of cesium from high-level waste

    SciTech Connect (OSTI)

    Bartsch, R.A.; Zhou, H.; Delmau, L.H.; Moyer, B.A.

    2008-07-01

    Using calix[4]arene as a scaffold, lipophilic, proton-ionizable ligands for cesium ion extraction have been synthesized. In the 1,3-alternate conformation, lipophilic octyl groups are attached to distal oxygens on one side of the calix[4]arene molecule, and an alkylated benzo-crown-6 unit is connected to distal oxygens on the other side. One phenyl octyl ether unit bears an acidic group in the para-position which orients it directly over the polyether ring. Solvent extractions of trace cesium ion from aqueous solutions into toluene have been performed. The efficiency of cesium ion extraction as a function of the aqueous phase pH and the identity of the acidic group have been assessed. Promising results are obtained for this new series of cesium ion extractants. (authors)

  10. ES&H development activities for the W89 warhead

    SciTech Connect (OSTI)

    Pretzel, C.W.

    1995-08-01

    Environmental, Safety and Health (ES&H) issues became an important design consideration during the development of the W89 warhead for the SRAM 11 (Short-Range Attack Missile) missile. An action plan was developed to handle these issues at all the production agencies and at both the system and the component level. The main thrust was in the area of solvent substitution, in particular for solder flux removal. The cleaner d-limonene followed by an isopropyl alcohol rinse was selected for applications were the traditional cleaners were 1,1,1 trichloroethane or trichloroethylene. Compatibility testing rather than efficacy testing dominated the development effort. In addition to other solvent substitution applications, organic materials that were free of toluene diisocynate (TDI), and methylene dianiline (MDA) were explored for use in the W89.

  11. Feasibility of actinide separation from UREX-like raffinates using a combination of sulfur- and oxygen-donor extractants

    SciTech Connect (OSTI)

    Zalupski, P.R.; Peterman, D.R.; Riddle, C.L.

    2013-07-01

    A synergistic combination of bis(o-trifluoromethylphenyl)dithios-phosphinic acid and trioctylphosphine oxide has been recently shown to selectively remove uranium, neptunium, plutonium and americium from aqueous environment containing up to 0.5 M nitric acid and 5.5 g/l fission products. Here the feasibility of performing this complete actinide recovery from aqueous mixtures is forecasted for a new organic formulation containing sulfur donor extractant of modified structure based on Am(III) and Eu(III) extraction data. A mixture of bis(bis-m,m-trifluoromethyl)phenyl)-dithios-phosphinic acid and TOPO in toluene enhances the extraction performance, accomplishing Am/Eu differentiation in aqueous mixtures up to 1 M nitric acid. The new organic recipe is also less susceptible to oxidative damage resulting from radiolysis. (authors)

  12. Feasibility of actinide separation from UREX-like raffinates using a combination of sulfur- and oxygen-donor extractants

    SciTech Connect (OSTI)

    Peter R. Zalupski; Dean R. Peterman; Catherine L. Riddle

    2013-09-01

    A synergistic combination of bis(o-trifluoromethylphenyl)dithiosphosphinic acid and trioctylphosphine oxide has been recently shown to selectively remove uranium, neptunium, plutonium and americium from aqueous environment containing up to 0.5 M nitric acid and 5.5 g/L fission products. Here the feasibility of performing this complete actinide recovery from aqueous mixtures is forecasted for a new organic formulation containing sulfur donor extractant of modified structure based on Am(III) and Eu(III) extraction data. A mixture of bis(bis-m,m-trifluoromethyl)phenyl)-dithiosphosphinic acid and TOPO in toluene enhances the extraction performance, accomplishing Am/Eu differentiation in aqueous mixtures up to 1 M nitric acid. The new organic recipe is also less susceptible to oxidative damage resulting from radiolysis.

  13. Non-covalent interactions of nitrous oxide with aromatic compounds: Spectroscopic and computational evidence for the formation of 1:1 complexes

    SciTech Connect (OSTI)

    Cao, Qian; School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275 ; Gor, Gennady Y.; Krogh-Jespersen, Karsten; Khriachtchev, Leonid

    2014-04-14

    We present the first study of intermolecular interactions between nitrous oxide (N{sub 2}O) and three representative aromatic compounds (ACs): phenol, cresol, and toluene. The infrared spectroscopic experiments were performed in a Ne matrix and were supported by high-level quantum chemical calculations. Comparisons of the calculated and experimental vibrational spectra provide direct identification and characterization of the 1:1 N{sub 2}O-AC complexes. Our results show that N{sub 2}O is capable of forming non-covalently bonded complexes with ACs. Complex formation is dominated by dispersion forces, and the interaction energies are relatively low (about ?3 kcal mol{sup ?1}); however, the complexes are clearly detected by frequency shifts of the characteristic bands. These results suggest that N{sub 2}O can be bound to the amino-acid residues tyrosine or phenylalanine in the form of ? complexes.

  14. Susceptibility of Aluminum Alloys to Corrosion in Simulated Fuel Blends Containing Ethanol

    SciTech Connect (OSTI)

    Thomson, Jeffery K; Pawel, Steven J; Wilson, Dane F

    2013-01-01

    The compatibility of aluminum and aluminum alloys with synthetic fuel blends comprised of ethanol and reference fuel C (a 50/50 mix of toluene and iso-octane) was examined as a function of water content and temperature. Commercially pure wrought aluminum and several cast aluminum alloys were observed to be similarly susceptible to substantial corrosion in dry (< 50 ppm water) ethanol. Corrosion rates of all the aluminum materials examined was accelerated by increased temperature and ethanol content in the fuel mixture, but inhibited by increased water content. Pretreatments designed to stabilize passive films on aluminum increased the incubation time for onset of corrosion, suggesting film stability is a significant factor in the mechanism of corrosion.

  15. Treatment of VOCs in high strength wastes using an anaerobic expanded-bed GAC reactor

    SciTech Connect (OSTI)

    Narayanian, B.; Suidan, M.T.; Gelderloos, A.B.; Brenner, R.C.

    1993-01-01

    The potential of the expanded-bed granular activated carbon (GAC) anaerobic reactor in treating a high strength waste containing RCRA volatile organic compounds (VOCs) was studied. A total of six VOCs, methylene chloride, chlorobenzene, carbon tetrachloride, chloroform, toluene and tetrachloroethylene, were fed to the reactor in a high strength matrix of background solvents. Performance was evaluated. The reactor was found to effect excellent removal of all VOCs (97%). Chloroform, while itself removed at levels in excess of 97%, was found to inhibit the degradation of acetate and acetone, two of the background solvents. Without any source of chloroform in the feed, excellent COD removals were obtained in addition to near-complete removal of all the VOCs.

  16. Aerosol characterization study using multi-spectrum remote sensing measurement techniques.

    SciTech Connect (OSTI)

    Glen, Crystal Chanea; Sanchez, Andres L.; Lucero, Gabriel Anthony; Schmitt, Randal L.; Johnson, Mark S.; Tezak, Matthew Stephen; Servantes, Brandon Lee

    2013-09-01

    A unique aerosol flow chamber coupled with a bistatic LIDAR system was implemented to measure the optical scattering cross sections and depolarization ratio of common atmospheric particulates. Each of seven particle types (ammonium sulfate, ammonium nitrate, sodium chloride, potassium chloride, black carbon and Arizona road dust) was aged by three anthropogenically relevant mechanisms: 1. Sulfuric acid deposition, 2. Toluene ozonolysis reactions, and 3. m-Xylene ozonolysis reactions. The results of pure particle scattering properties were compared with their aged equivalents. Results show that as most particles age under industrial plume conditions, their scattering cross sections are similar to pure black carbon, which has significant impacts to our understanding of aerosol impacts on climate. In addition, evidence emerges that suggest chloride-containing aerosols are chemically altered during the organic aging process. Here we present the direct measured scattering cross section and depolarization ratios for pure and aged atmospheric particulates.

  17. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    SciTech Connect (OSTI)

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-09-18

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies an airflow rate of 5000 lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.

  18. Separation and concentration of lower alcohols from dilute aqueous solutions

    DOE Patents [OSTI]

    Moore, Raymond H.; Eakin, David E.; Baker, Eddie G.; Hallen, Richard T.

    1991-01-01

    A process for producing, from a dilute aqueous solution of a lower (C.sub.1 -C.sub.5) alcohol, a concentrated liquid solution of the alcohol in an aromatic organic solvent is disclosed. Most of the water is removed from the dilute aqueous solution of alcohol by chilling sufficiently to form ice crystals. Simultaneously, the remaining liquid is extracted at substantially the same low temperature with a liquid organic solvent that is substantially immiscible in aqueous liquids and has an affinity for the alcohol at that temperature, causing the alcohol to transfer to the organic phase. After separating the organic liquid from the ice crystals, the organic liquid can be distilled to enrich the concentration of alcohol therein. Ethanol so separated from water and concentrated in an organic solvent such as toluene is useful as an anti-knock additive for gasoline.

  19. Aromatic and polycyclic aromatic hydrocarbon formation in a laminar premixed n-butane flame

    SciTech Connect (OSTI)

    Marinov, N.M.; Pitz, W.J.; Westbrook, C.K.; Vincitore, A.M.; Castaldi, M.J.; Senkan, S.M.; Melius, C.F.

    1998-07-01

    Experimental and detailed chemical kinetic modeling work has been performed to investigate aromatic and polycyclic aromatic hydrocarbon (PAH) formation pathways in a premixed, rich, sooting, n-butane-oxygen-argon burner stabilized flame. An atmospheric pressure, laminar flat flame operated at an equivalence ratio of 2.6 was used to acquire experimental data for model validation. Gas composition analysis was conducted by an on-line gas chromatograph/mass spectrometer technique. Measurements were made in the main reaction and post-reaction zones for a number of low molecular weight species, aliphatics, aromatics, and polycyclic aromatic hydrocarbons (PAHs) ranging from two to five-fused aromatic rings. Reaction flux and sensitivity analysis were used to help identify the important reaction sequences leading to aromatic and PAH growth and destruction in the n-butane flame. Reaction flux analysis showed the propargyl recombination reaction was the dominant pathway to benzene formation. The consumption of propargyl by H atoms was shown to limit propargyl, benzene, and naphthalene formation in flames as exhibited by the large negative sensitivity coefficients. Naphthalene and phenanthrene production was shown to be plausibly formed through reactions involving resonantly stabilized cyclopentadienyl and indenyl radicals. Many of the low molecular weight aliphatics, combustion by-products, aromatics, branched aromatics, and PAHs were fairly well simulated by the model. Additional work is required to understand the formation mechanisms of phenyl acetylene, pyrene, and fluoranthene in the n-butane flame. 73 refs.

  20. Low temperature pyrotechnic smokes: A potential low cost alternative to nonpyrotechnic smoke for access delay applications

    SciTech Connect (OSTI)

    Greenholt, C.J.

    1995-07-01

    Smokes are frequently used as visual obscurants in access delay applications. A new generation of low temperature pyrotechnic smokes is being developed. Terephthalic Acid (TPA) smoke was developed by the U.S. Army and Sebacic Acid (SA) smoke is being developed by Thiokol Corp. The advantages these smokes offer over traditional pyrotechnic smokes include; low generation temperature (approximately 450{degree}C), lower toxicity, and lower corrosivity. The low generation temperature reduces smoke layering effects and allows the addition of sensory irritants, such as o-Chlorobenzylidene Malononitrile (CS), to the formulation. Some advantages low temperature pyrotechnic smokes offer over nonpyrotechnic smokes include; low cost, simplicity, compactness, light weight, long storage life, and orientation insensitive operation. Low cost permits distribution of multiple units for reduced vulnerability and refill flexibility. Some disadvantages may include the combustibility of the smoke particulate; however, the published lower explosive limit of the mentioned materials is approximately ten times greater than the concentration required for effective obscuration. The TPA smoke cloud contains small quantities of benzene, formaldehyde, and carbon monoxide; no benzene or formaldehyde was identified during preliminary SA smoke analyses performed by Thiokol Corp. Sandia performed tests and analyses on TPA smoke to determine the smoke cloud composition, the quantity of particulate produced per canister, and the relationship between airborne particulate concentration and measured optical density values. Current activities include characterization of SA smoke.

  1. Ammonia removal process upgrade to the Acme Steel Coke Plant

    SciTech Connect (OSTI)

    Harris, J.L.

    1995-12-01

    The need to upgrade the ammonia removal process at the Acme Steel Coke Plant developed with the installation of the benzene NESHAP (National Emission Standard for Hazardous Air Pollutants) equipment, specifically the replacement of the final cooler. At Acme Steel it was decided to replace the existing open cooling tower type final cooler with a closed loop direct spray tar/water final cooler. This new cooler has greatly reduced the emissions of benzene, ammonia, hydrogen sulfide and hydrogen cyanide to the atmosphere, bringing them into environmental compliance. At the time of its installation it was not fully recognized as to the effect this would have on the coke oven gas composition. In the late seventies the decision had been made at Acme Steel to stop the production of ammonia sulfate salt crystals. The direction chosen was to make a liquid ammonia sulfate solution. This product was used as a pickle liquor at first and then as a liquid fertilizer as more markets were developed. In the fall of 1986 the ammonia still was brought on line. The vapors generated from the operation of the stripping still are directed to the inlet of the ammonia absorber. At that point in time it was decided that an improvement to the cyclical ammonia removal process was needed. The improvements made were minimal yet allowed the circulation of solution through the ammonia absorber on a continuous basis. The paper describes the original batch process and the modifications made which allowed continuous removal.

  2. Fabrication of oriented zeolite L monolayer via covalent molecular linkers

    SciTech Connect (OSTI)

    Wang Yige; Li Huanrong Liu Binyuan; Gan Quanying; Dong Qinglin; Calzaferri, Gion; Sun Zheng

    2008-09-15

    For the first time, 1,4-diisocyanatobutane (DICB) was used as the covalent molecular linker in this study to prepare the uniformly oriented zeolite L monolayer with relatively high coverage degree and close packing degree. This could be ascribed to substantial amounts of DICB self-assemble and standing on the substrate surface instead of folding up into a U-shape. This point has been further verified by the quality of oriented zoelite L monolayers obtained from the procedure involving DICB, 1, 4-bis (triethoxysilyl) benzene (BTSEB) and 1,2-bis(trimethoxysilyl)ethane (BTMSE) as covalent molecular linkers. - Graphical abstract: 1, 4-diisocyanatobutane (DICB) was used as the covalent molecular linker in this study to prepare the uniformly oriented zeolite L monolayer with a relatively high coverage degree and close packing degree. This could be ascribed to substantial amounts of DICB self-assemble and standing on the substrate surface instead of folding up into a U-shape. This point has been further verified by the quality of oriented zoelite L monolayers obtained from the procedure involving DICB, 1, 4-bis (triethoxysilyl) benzene (BTSEB) and 1,2-bis(trimethoxysilyl)ethane (BTMSE) as covalent molecular linkers.

  3. Molecular and crystal structure of n-hexyloxybenzoic anhydride at low and room temperatures

    SciTech Connect (OSTI)

    Konstantinov, I. I.; Churakov, A. V.; Kuz'mina, L. G.

    2010-09-15

    The crystal and molecular structures of n-hexyloxybenzoic anhydride, C{sub 6}H{sub 13}-O-C{sub 6}H{sub 4}-C(O)-O-C(O)-C{sub 6}H{sub 4}-C{sub 6}H{sub 13}, at low (120 K) and room (296 K) temperatures have been investigated. The molecule has an asymmetric bent structure. The dihedral angle between the benzene ring planes is 48.5 deg. The aliphatic chain on one side of the molecule has a transoid orientation with respect to the 'internal' C4 atom of the closest benzene ring, whereas the aliphatic chain on the other side has a cissoid orientation with respect to the analogous C(4A) atom. The crystal packing does not exhibit any pronounced separation of the crystal space into closely packed aromatic or loosely packed aliphatic regions. No weak directional interactions are observed in the packing; this fact explains the absence of liquid-crystal properties for this compound.

  4. Preparation of hydrophobic organic aeorgels

    DOE Patents [OSTI]

    Baumann, Theodore F.; Satcher, Jr., Joe H.; Gash, Alexander E.

    2004-10-19

    Synthetic methods for the preparation of hydrophobic organics aerogels. One method involves the sol-gel polymerization of 1,3-dimethoxybenzene or 1,3,5-trimethoxybenzene with formaldehyde in non-aqueous solvents. Using a procedure analogous to the preparation of resorcinol-formaldehyde (RF) aerogels, this approach generates wet gels that can be dried using either supercritical solvent extraction to generate the new organic aerogels or air dried to produce an xerogel. Other methods involve the sol-gel polymerization of 1,3,5 trihydroxy benzene (phloroglucinol) or 1,3 dihydroxy benzene (resorcinol) and various aldehydes in non-aqueous solvents. These methods use a procedure analogous to the one-step base and two-step base/acid catalyzed polycondensation of phloroglucinol and formaldehyde, but the base catalyst used is triethylamine. These methods can be applied to a variety of other sol-gel precursors and solvent systems. These hydrophobic organics aerogels have numerous application potentials in the field of material absorbers and water-proof insulation.

  5. Preparation of hydrophobic organic aeorgels

    DOE Patents [OSTI]

    Baumann, Theodore F.; Satcher, Jr., Joe H.; Gash, Alexander E.

    2007-11-06

    Synthetic methods for the preparation of hydrophobic organics aerogels. One method involves the sol-gel polymerization of 1,3-dimethoxybenzene or 1,3,5-trimethoxybenzene with formaldehyde in non-aqueous solvents. Using a procedure analogous to the preparation of resorcinol-formaldehyde (RF) aerogels, this approach generates wet gels that can be dried using either supercritical solvent extraction to generate the new organic aerogels or air dried to produce an xerogel. Other methods involve the sol-gel polymerization of 1,3,5 trihydroxy benzene (phloroglucinol) or 1,3 dihydroxy benzene (resorcinol) and various aldehydes in non-aqueous solvents. These methods use a procedure analogous to the one-step base and two-step base/acid catalyzed polycondensation of phloroglucinol and formaldehyde, but the base catalyst used is triethylamine. These methods can be applied to a variety of other sol-gel precursors and solvent systems. These hydrophobic organics aerogels have numerous application potentials in the field of material absorbers and water-proof insulation.

  6. Experimental and modeling investigation of aromatic and polycyclic aromatic hydrocarbon formation in a premixed ethylene flame

    SciTech Connect (OSTI)

    Castaldi, M.J.; Marinov, N.M.; Melius, C.F.

    1996-02-01

    Experimental and detailed chemical kinetic modeling has been performed to investigate aromatic and polyaromatic hydrocarbon formation pathways in a rich, sooting, ethylene-oxygen-argon premixed flame. An atmospheric pressure, laminar flat flame operated at an equivalence ratio of 2.5 was used to acquire experimental data for model validation. Gas composition analysis was conducted by an on-line gas chromatograph/mass spectrometer (GC/MS) technique. Measurements were made in the flame and post-flame zone for a number of low molecular weight species, aliphatics, aromatics and polycyclic aromatic hydrocarbons (PAHs) ranging from two to five-aromatic fused rings. The modeling results show the key reaction sequences leading to aromatic and polycyclic aromatic hydrocarbon growth involve the combination of resonantly stabilized radicals. In particular, propargyl and 1-methylallenyl combination reactions lead to benzene and methyl substituted benzene formation, while polycyclic aromatics are formed from cyclopentadienyl radicals and fused rings that have a shared C{sub 5} side structure. Naphthalene production through the reaction step of cyclopentadienyl self-combination and phenanthrene formation from indenyl and cyclopentadienyl combination were shown to be important in the flame modeling study. The removal of phenyl by O{sub 2} leading to cyclopentadienyl formation is expected to play a pivotal role in the PAH or soot precursor growth process under fuel-rich oxidation conditions.

  7. Ultrapyrolytic upgrading of plastic wastes and plastics/heavy oil mixtures to valuable light gas products

    SciTech Connect (OSTI)

    Lovett, S.; Berruti, F.; Behie, L.A.

    1997-11-01

    Viable operating conditions were identified experimentally for maximizing the production of high-value products such as ethylene, propylene, styrene, and benzene, from the ultrapyrolysis of waste plastics. Using both a batch microreactor and a pilot-plant-sized reactor, the key operating variables considered were pyrolysis temperature, product reaction time, and quench time. In the microreactor experiments, polystyrene (PS), a significant component of waste plastics, was pyrolyzed at temperatures ranging from 800 to 965 C, with total reaction times ranging from 500 to 1,000 ms. At a temperature of 965 C and 500 ms, the yields of styrene plus benzene were greater than 95 wt %. In the pilot-plant experiments, the recently patented internally circulating fluidized bed (ICFB) reactor (Milne et al., US Patent Number 5,370,789, 1994b) was used to ultrapyrolyze low-density polyethylene (LDPE) in addition to LDPE (5% by weight)/heavy oil mixtures at a residence time of 600 ms. Both experiments produced light olefin yields greater than 55 wt % at temperatures above 830 C.

  8. Intensity-resolved ionization yields of aniline with femtosecond laser pulses

    SciTech Connect (OSTI)

    Strohaber, J.; Hart, N.; Zhu, F.; Nava, R.; Pham, F.; Kolomenskii, A. A.; Paulus, G. G.; Schuessler, H. A.; Mohamed, T.; Schroeder, H.

    2011-12-15

    We present experimental results for the ionization of aniline and benzene molecules subjected to intense ultrashort laser pulses. Measured parent molecular ions yields were obtained using a recently developed technique capable of three-dimensional imaging of ion distributions within the focus of a laser beam. By selecting ions originating from the central region of the focus, where the spatial intensity distribution is nearly uniform, volumetric-free intensity-dependent ionization yields were obtained. The measured data revealed a previously unseen resonance-enhanced multiphoton ionization (REMPI)-like process. Comparison of benzene, aniline, and Xe ion yields demonstrates that the observed intensity-dependent structures are not due to geometric artifacts in the focus. Finally for intensities greater than {approx}3x10{sup 13} W/cm{sup 2}, we attribute the ionization of aniline to a stepwise process going through the {pi}{sigma}{sup *} state which sits three photons above the ground state and two photons below the continuum.

  9. In situ Formation of Highly Conducting Covalent Au-C Contacts for Single-Molecule Junctions

    SciTech Connect (OSTI)

    Cheng, Z.L.; Hybertsen, M.; Skouta, R.; Vazquez, H.; Widawsky, J.R.; Schneebeli, S.; Chen, W.; Breslow, R.; Venkataraman, L.

    2011-06-01

    Charge transport across metal-molecule interfaces has an important role in organic electronics. Typically, chemical link groups such as thiols or amines are used to bind organic molecules to metal electrodes in single-molecule circuits, with these groups controlling both the physical structure and the electronic coupling at the interface. Direct metal-carbon coupling has been shown through C60, benzene and {pi}-stacked benzene but ideally the carbon backbone of the molecule should be covalently bonded to the electrode without intervening link groups. Here, we demonstrate a method to create junctions with such contacts. Trimethyl tin (SnMe{sub 3})-terminated polymethylene chains are used to form single-molecule junctions with a break-junction technique. Gold atoms at the electrode displace the SnMe{sub 3} linkers, leading to the formation of direct Au-C bonded single-molecule junctions with a conductance that is {approx}100 times larger than analogous alkanes with most other terminations. The conductance of these Au-C bonded alkanes decreases exponentially with molecular length, with a decay constant of 0.97 per methylene, consistent with a non-resonant transport mechanism. Control experiments and ab initio calculations show that high conductances are achieved because a covalent Au-C sigma ({sigma}) bond is formed. This offers a new method for making reproducible and highly conducting metal-organic contacts.

  10. Electronic states of thiophene/phenylene co-oligomers: Extreme-ultra violet excited photoelectron spectroscopy observations and density functional theory calculations

    SciTech Connect (OSTI)

    Kawaguchi, Yoshizo; Sasaki, Fumio; Mochizuki, Hiroyuki; Ishitsuka, Tomoaki; Tomie, Toshihisa; Ootsuka, Teruhisa; Watanabe, Shuji; Shimoi, Yukihiro; Yamao, Takeshi; Hotta, Shu

    2013-02-28

    We have investigated electronic states in the valence electron bands for the thin films of three thiophene/phenylene co-oligomer (TPCO) compounds, 2,5-bis(4-biphenylyl)thiophene (BP1T), 1,4-bis(5-phenylthiophen-2-yl)benzene (AC5), and 1,4-bis{l_brace}5-[4-(trifluoromethyl)phenyl]thiophen-2-yl{r_brace}benzene (AC5-CF{sub 3}), by using extreme-UV excited photoelectron spectroscopy (EUPS). By comparing both EUPS spectra and secondary electron spectra between AC5 and AC5-CF{sub 3}, we confirm that CF{sub 3} substitution to AC5 deepens valence states by 2 eV, and increases the ionization energy by 3 eV. From the cut-off positions of secondary electron spectra, the work functions of AC5, AC5-CF{sub 3}, and BP1T are evaluated to be 3.8 eV, 4.8 eV, and 4.0 eV, respectively. We calculate molecular orbital (MO) energy levels by the density functional theory and compare results of calculations with those of experiments. Densities of states obtained by broadening MO levels well explain the overall features of experimental EUPS spectra of three TPCOs.

  11. Effect of carboxylic acid of periodic mesoporous organosilicas on the fructose-to-5-hydroxymethylfurfural conversion in dimethylsulfoxide systems

    SciTech Connect (OSTI)

    Dutta, Saikat; Wu, Kevin C.-W. E-mail: kevinwu@ntu.edu.tw; Kao, Hsien-Ming E-mail: kevinwu@ntu.edu.tw

    2014-11-01

    This manuscript presents the preparation and catalytic application of highly ordered benzene bridged periodic mesoporous organosilicas (PMOs) functionalized with carboxylic acid (–COOH) group at varied density. The COOH-functionalized PMOs were synthesized by one-step condensation of 1,4-bis (triethoxysilyl) benzene and carboxylic group containing organosilane carboxyethylsilanetriol sodium salt using Brij-76 as the template. The obtained materials were characterized by a mean of methods including powder X-ray diffraction, nitrogen adsorption-desorption, scanning- and transmission electron microscopy, and {sup 13}C solid-state nuclear magnetic resonance measurements. The potentials of the obtained PMO materials with ordered mesopores were examined as solid catalysts for the chemical conversion of fructose to 5-hydroxymethylfurfural (HMF) in an organic solvent. The results showed that COOH-functionalized PMO with 10% COOH loading exhibited best results for the fructose to HMF conversion and selectivity. The high surface area, the adequate density acid functional group, and the strength of the PMO materials contributing to a promising catalytic ability were observed.

  12. Including screening in van der Waals corrected density functional theory calculations: The case of atoms and small molecules physisorbed on graphene

    SciTech Connect (OSTI)

    Silvestrelli, Pier Luigi; Ambrosetti, Alberto

    2014-03-28

    The Density Functional Theory (DFT)/van der Waals-Quantum Harmonic Oscillator-Wannier function (vdW-QHO-WF) method, recently developed to include the vdW interactions in approximated DFT by combining the quantum harmonic oscillator model with the maximally localized Wannier function technique, is applied to the cases of atoms and small molecules (X=Ar, CO, H{sub 2}, H{sub 2}O) weakly interacting with benzene and with the ideal planar graphene surface. Comparison is also presented with the results obtained by other DFT vdW-corrected schemes, including PBE+D, vdW-DF, vdW-DF2, rVV10, and by the simpler Local Density Approximation (LDA) and semilocal generalized gradient approximation approaches. While for the X-benzene systems all the considered vdW-corrected schemes perform reasonably well, it turns out that an accurate description of the X-graphene interaction requires a proper treatment of many-body contributions and of short-range screening effects, as demonstrated by adopting an improved version of the DFT/vdW-QHO-WF method. We also comment on the widespread attitude of relying on LDA to get a rough description of weakly interacting systems.

  13. Preparation of Gd Loaded Liquid Scintillator for Daya Bay Neutrino Experiment

    SciTech Connect (OSTI)

    Ding Yayun; Zhang Zhiyong

    2010-05-12

    Gadolinium loaded liquid scintillator (Gd-LS) is an excellent target material for reactor antineutrino experiments. Ideal Gd-LS should have long attenuation length, high light yield, long term stability, low toxicity, and should be compatible with the material used to build the detector. We have developed a new Gd-LS recipe in which carboxylic acid 3,5,5-trimethylhexanoic acid is used as the complexing ligand to gadolinium, 2,5-diphenyloxazole (PPO) and 1,4-bis[2-methylstyryl]benzene (bis-MSB) are used as primary fluor and wavelength shifter, respectively. The scintillator base is linear alkyl benzene (LAB). Eight hundred liters of Gd-LS has been synthesized and tested in a prototype detector. Results show that the Gd-LS has high quality and is suitable for underground experiments in large quantity. Large scale production facility has been built. A full batch production of 4 t Gd-LS has been produced and monitored for several months. The production of 180 t Gd-LS will be carried out in the near future.

  14. Composition of motor-vehicle organic emissions under elevated-temperature summer driving conditions (75 to 105 deg F)

    SciTech Connect (OSTI)

    Stump, F.D.; Knapp, K.T.; Ray, W.D.; Snow, R.; Burton, C.

    1992-01-01

    Emissions from seven late-model popular V-6 and V-8 motor vehicles were characterized at three test temperatures. The Urban Dynamometer Driving Schedule was used for vehicle tailpipe testing. Six vehicles fueled by port fuel injection (PFI) and one vehicle with a carbureted fuel system were tested at temperatures of 75, 90, and 105 F with unleaded regular summer grade gasoline. Tailpipe and evaporative emissions were determined at each test temperature. Measured emissions were the total hydrocarbons (THCs), speciated hydrocarbons, speciated aldehydes, carbon monoxide (CO), oxides of nitrogen (NOx), benzene, and 1,3-butadiene. In general, tailpipe emissions of THC, benzene, and 1,3-butadiene from the vehicles were not temperature sensitive, but the CO and NOx emissions showed some temperature sensitivity. Formaldehyde, acetaldehyde, and total aldehyde emissions from the PFI vehicles were also not temperature dependent, while formaldehyde emissions from the carbureted vehicle decreased slightly with increasing test temperature. Evaporative THC emissions generally increased with increasing test temperature. Hydrocarbon emissions saturated and broke through the evaporative carbon canister of one PFI vehicle during the 105 F hot soak while the other six vehicles showed no hydrocarbon breakthrough.

  15. Identification of biological processes in a mixed hydrocarbon plume at a paint manufacturing facility

    SciTech Connect (OSTI)

    McLaughlan, R.G.; Walsh, K.P.; Henkler, R.D.; Anderson, B.N.

    1996-12-31

    In situ biodegradation is increasingly being used as a cost effective remedial strategy for contaminated sites. However, for the remediation to be successful, it is necessary to understand the fundamental geochemical and microbiological processes occurring at a particular site. At a paint manufacturing facility, a mixed hydrocarbon plume containing both BTEX and paraffinic hydrocarbons (Stoddard solvent) has contaminated the aquifer. The microbial processes occurring in the plume were investigated to better define the capacity of the aquifer to degrade hydrocarbons. Microbial oxidation of hydrocarbons is known to be coupled with the reduction of redox active species including oxygen, nitrate, ferric iron and sulphate as well as the production of methane. Water quality data, redox parameters and contaminant information were collected from the site to identify candidate biological processes occurring. The results show that as the contaminant concentration increases, the redox decreases indicating the generation of a more reduced environment. The decreasing redox correlates with increased concentrations of ammonia, ferrous iron and sulphide. The data indicates that there have been a range of different electron acceptor systems operating at the site. This has been correlated with a theoretical amount of benzene consumed. The chemistry from the wells at the site show that at least 47 mg/L of benzene is capable of being mineralized within the aquifer by microbial based transformations given the current contaminant loading and flowrate. 3 refs., 1 fig., 2 tabs.

  16. Lignin-assisted coal depolymerization. [Quarterly] report, March 1, 1992--May 31, 1992

    SciTech Connect (OSTI)

    Lalvani, S.B.; Muchmore, C.B.; Koropchak, J.A.; Kim, Jong Won

    1992-10-01

    In the last report, it was shown that when lignin is added to coal, the rate of coal depolymerization is enhanced. The results,-reported were based upon a number of experiments conducted for the following three reasons: (i) to generate enough quantities of liquid products so that their stability in various environments can be ascertained, (ii) to closely characterize the reaction products, so that individual atomic mass balances can be performed, and (iii) to determine the reproducibility of the experiments conducted. The stability of liquid products was characterized by determining their solubility in pentane and benzene. Exposure of the coal- and coal+lignin-derived liquids to air at 40 and 80{degrees}C led to a decrease in the pentane-soluble and asphaltene fractions with a concomitant enhancement in the benzene insoluble fraction. However, relatively no degradation was observed for the liquid samples exposed to an inert (N{sub 2}) atmosphere. Preliminary data show that the coal+lignin-derived liquids are more stable than that obtained by coal liquefaction. In this quarterly report, individual atomic mass balances on various experiments conducted with coal, lignin and coal+lignin mixtures are also reported. Although the overall mass recoveries of 95--98% of the total mass charged to the reactor were obtained, the atomic mass balance data are somewhat difficult to interpret due to the possible incorporation of tetralin (solvent) in the reaction products.

  17. Heavy Oil Process Monitor: Automated On-Column Asphaltene Precipitation and Re-Dissolution

    SciTech Connect (OSTI)

    John F. Schabron; Joseph F. Rovani; Mark Sanderson

    2007-03-31

    An automated separation technique was developed that provides a new approach to measuring the distribution profiles of the most polar, or asphaltenic components of an oil, using a continuous flow system to precipitate and re-dissolve asphaltenes from the oil. Methods of analysis based on this new technique were explored. One method based on the new technique involves precipitation of a portion of residua sample in heptane on a polytetrafluoroethylene-packed (PTFE) column. The precipitated material is re-dissolved in three steps using solvents of increasing polarity: cyclohexane, toluene, and methylene chloride. The amount of asphaltenes that dissolve in cyclohexane is a useful diagnostic of the thermal history of oil, and its proximity to coke formation. For example, about 40 % (w/w) of the heptane asphaltenes from unpyrolyzed residua dissolves in cyclohexane. As pyrolysis progresses, this number decrease to below 15% as coke and toluene insoluble pre-coke materials appear. Currently, the procedure for the isolation of heptane asphaltenes and the determination of the amount of asphaltenes soluble in cyclohexane spans three days. The automated procedure takes one hour. Another method uses a single solvent, methylene chloride, to re-dissolve the material that precipitates on heptane on the PTFE-packed column. The area of this second peak can be used to calculate a value which correlates with gravimetric asphaltene content. Currently the gravimetric procedure to determine asphaltenes takes about 24 hours. The automated procedure takes 30 minutes. Results for four series of original and pyrolyzed residua were compared with data from the gravimetric methods. Methods based on the new on-column precipitation and re-dissolution technique provide significantly more detail about the polar constituent's oils than the gravimetric determination of asphaltenes.

  18. Preparation of water soluble L-arginine capped CdSe/ZnS QDs and their interaction with synthetic DNA: Picosecond-resolved FRET study

    SciTech Connect (OSTI)

    Giri, Anupam; Goswami, Nirmal; Lemmens, Peter; Pal, Samir Kumar

    2012-08-15

    Graphical abstract: Förster resonance energy transfer (FRET) studies on the interaction of water soluble arginine-capped CdSe/ZnS QDs with ethidium bromide (EB) labeled synthetic dodecamer DNA. Highlights: ? We have solubilized CdSe/ZnS QD in water replacing their TOPO ligand by L-arginine. ? We have studied arginine@QD–DNA interaction using FRET technique. ? Arginine@QDs act as energy donor and ethidium bromide-DNA acts as energy acceptor. ? We have applied a kinetic model to understand the kinetics of energy transfer. ? Circular dichroism studies revealed negligible perturbation in the DNA B-form in the arg@QD-DNA complex. -- Abstract: We have exchanged TOPO (trioctylphosphine oxide) ligand of CdSe/ZnS core/shell quantum dots (QDs) with an amino acid L-arginine (Arg) at the toluene/water interface and eventually rendered the QDs from toluene to aqueous phase. We have studied the interaction of the water soluble Arg-capped QDs (energy donor) with ethidium (EB) labeled synthetic dodecamer DNA (energy acceptor) using picoseconds resolved Förster resonance energy transfer (FRET) technique. Furthermore, we have applied a model developed by M. Tachiya to understand the kinetics of energy transfer and the distribution of acceptor (EB-DNA) molecules around the donor QDs. Circular dichroism (CD) studies revealed a negligible perturbation in the native B-form structure of the DNA upon interaction with Arg-capped QDs. The melting and the rehybridization pathways of the DNA attached to the QDs have been monitored by the CD which reveals hydrogen bonding is the associative mechanism for interaction between Arg-capped QDs and DNA.

  19. Tracking a defined route for O[subscript 2] migration in a dioxygen-activating diiron enzyme

    SciTech Connect (OSTI)

    Song, Woon Ju; Gucinski, Grant; Sazinsky, Matthew H.; Lippard, Stephen J. (MIT); (Pomona)

    2011-09-08

    For numerous enzymes reactive toward small gaseous compounds, growing evidence indicates that these substrates diffuse into active site pockets through defined pathways in the protein matrix. Toluene/o-xylene monooxygenase hydroxylase is a dioxygen-activating enzyme. Structural analysis suggests two possible pathways for dioxygen access through the {alpha}-subunit to the diiron center: a channel or a series of hydrophobic cavities. To distinguish which is utilized as the O{sub 2} migration pathway, the dimensions of the cavities and the channel were independently varied by site-directed mutagenesis and confirmed by X-ray crystallography. The rate constants for dioxygen access to the diiron center were derived from the formation rates of a peroxodiiron(III) intermediate, generated upon treatment of the diiron(II) enzyme with O2. This reaction depends on the concentration of dioxygen to the first order. Altering the dimensions of the cavities, but not the channel, changed the rate of dioxygen reactivity with the enzyme. These results strongly suggest that voids comprising the cavities in toluene/o-xylene monooxygenase hydroxylase are not artifacts of protein packing/folding, but rather programmed routes for dioxygen migration through the protein matrix. Because the cavities are not fully connected into the diiron active center in the enzyme resting state, conformational changes will be required to facilitate dioxygen access to the diiron center. We propose that such temporary opening and closing of the cavities may occur in all bacterial multicomponent monooxygenases to control O{sub 2} consumption for efficient catalysis. Our findings suggest that other gas-utilizing enzymes may employ similar structural features to effect substrate passage through a protein matrix.

  20. Studies on the catalytic activity of zirconia promoted with sulfate, iron, and manganese

    SciTech Connect (OSTI)

    Wan, K.T.; Khouw, C.B.; Davis, M.E.

    1996-01-01

    The catalytic properties of iron- and manganese-promoted sulfated zirconia (SFMZ) for the isomerization of n-butane to isobutane are investigated using various catalyst pretreatments and reaction conditions. The n-butane isomerization reactivity at 30{degrees}C is effected by calcination of the catalyst at 650{degrees}C in helium and vacuum treatment at room temperature indicating that superacidity is not likely to be responsible for activity. In addition, SFMZ samples exposed to dry air at over 450{degrees}C are more active than those calcined in helium at a reaction temperature of 30{degrees}C (n-butane conversions of 18.7% vs 0.4%) suggesting the presence of an active site involving a metal {open_quotes}oxy{close_quotes} species. The oxy species is capable of reacting CO to CO{sub 2} at room temperature and is present at a number density of 10-15 {mu}mol/g. At a reaction temperature of 100{degrees}C, SFMZ catalysts calcined in air then activated in helium show similar reactivities to those activated in air up to a preheating temperature of 450{degrees}C; above 450{degrees}C the metal oxy species is formed and provides additional activity (n-butane conversions of 37.1% in air vs 15.4% in He for calcinations at 650{degrees}C). The nature of the active sites on SFMZ are investigated using temperature-programmed desorption of substituted benzenes. The liberation of CO{sub 2} and SO{sub 2} in the benzene TPD profile of SFMZ is attributed to the oxidation of benzene at the redox-active metal sites, resulting in the subsequent decomposition of the reduced iron (II) sulfate. Data from the TPD studies do not suggest the presence of superacidity on SFMZ that could contribute to the low-temperature n-butane isomerization activity. Instead, a bifunctional mechanism that involves a combination of a redox-active metal site and an acid site in close proximity is proposed. 62 refs., 17 figs., 4 tabs.

  1. Influence of biphenyl spacer appended to the flexible phosphonate arms in modulating the dimensionality of the coordination polymers: Synthesis, structural chemistry and magnetic properties

    SciTech Connect (OSTI)

    Tripuramallu, Bharat Kumar; Das, Samar K.

    2013-01-15

    Two new compounds [Co (2,2 Prime -bipy) (H{sub 2}dbp)]{sub n} (1) and [Ni (2,2 Prime -bipy){sub 2}(H{sub 2}dbp)(H{sub 2}O)]{center_dot}H{sub 2}O (2) based on the flexible ligand 4,4 Prime -dimethylenebiphenyldiphosphonic acid (H{sub 4}dbp) with 2,2 Prime -bipyridine as secondary ligand have been synthesized under hydrothermal conditions. Both the compounds are well characterized by routine elemental analysis, IR, electronic spectroscopies, thermogravimetric analysis and finally by single crystal X-ray diffraction analysis. Compound 1 is a 1D extended coordination polymer and 2 is a discrete molecular compound. A comparative study between the geometries of H{sub 4}dbp ligand (in compounds 1 and 2, present study) and p-xylylenediphosphonic acid (H{sub 4}pxp) ligand (in previously reported compounds [Cu(2,2 Prime -bipy)(H{sub 2}pxp)]{center_dot}nH{sub 2}O (1A) and Ni(2,2 Prime -bipy){sub 2}H{sub 4}pxp]{sub n}[H{sub 2}pxp]{sub n} (2A), see text) demonstrate the effect of the twisting in the benzene rings in changing higher dimensional H{sub x}pxp (x refers to number of protonated hydroxyl groups) compounds to lower dimensional H{sub x}dbp compounds. The eight membered Co-dimer rings formed in compound 1 represents the simple and isolated Co-dimer, exhibiting weak antiferromagnetic exchange between metal centers through OPO bridges. - Graphical abstract: Two new compounds based on the dimethylenebiphenyldiphosphonic acid have been synthesized. The effect of twisting of benzene rings in the biphenyl spacer containing multidentate ligands alters dimensionality of final compounds. Highlights: Black-Right-Pointing-Pointer Cobalt containing coordination polymer and a nickel discrete compound have been synthesized. Black-Right-Pointing-Pointer Flexible ligand 4,4'-dimethylenebiphenyldiphosphonic acid has been employed. Black-Right-Pointing-Pointer Co(II) and Ni(II) ions are square pyramidal and octahedral respectively. Black-Right-Pointing-Pointer The effect of the twisting in the benzene rings in the associated ligand has been demonstrated.

  2. Development of Chemical Treatment Alternatives for Tetraphenylborate Destruction in Tank 48H

    SciTech Connect (OSTI)

    LAMBERT, DANIELP.

    2004-05-04

    This study assessed chemical treatment options for decomposing the tetraphenylborate in High Level Waste (HLW) Tank 48H. Tank 48H, located at the Savannah River Site in Aiken, SC, contains approximately one million liters of HLW. The tetraphenylborate slurry represents legacy material from commissioning of an In Tank Precipitation process to separate radioactive cesium and actinides from the non radioactive chemicals. During early operations, the process encountered an unplanned chemical reaction that catalytically decomposed the excess tetraphenylborate producing benzene. Subsequent research indicated that personnel could not control the operations within the existing equipment to both meet the desired treatment rate for the waste and maintain the benzene concentration within allowable concentrations. Since then, the Department of Energy selected an alternate treatment process for handling high-level waste at the site. However, the site must destroy the tetraphenylborate before returning the tank to HLW service. The research focuses on identifying treatments to decompose tetraphenylborate to the maximum extent feasible, with a preference for decomposition methods that produce carbon dioxide rather than benzene. A number of experiments examined whether the use of oxidants, catalysts or acids proved effective in decomposing the tetraphenylborate. Additional experiments developed an understanding of the solid, liquid and gas decomposition products. The testing identified several successful treatment options including: an iron catalyst combined with hydrogen peroxide (Fenton's reagent) with added acid; sodium permanganate with added acid; and copper catalyst with added acid. A mistake occurred in the selection and make-up of the Tank 48H simulant recipe which led to an under representation of the amount of monosodium titanate and insoluble sludge solids compared to the simulant target. The amount of added MST and sludge proved about a factor of 40 low relative to the measured Tank 48H values. The MST and sludge are insoluble solids that were likely inert in the testing completed. As a result, the mistake had no impact on the testing. Any future Tank 48H research should be completed using the latest Tank 48H simulant recipe.

  3. Progress toward Biomass and Coal-Derived Syngas Warm Cleanup: Proof-of-Concept Process Demonstration of Multicontaminant Removal for Biomass Application

    SciTech Connect (OSTI)

    Howard, Christopher J.; Dagle, Robert A.; Lebarbier, Vanessa MC; Rainbolt, James E.; Li, Liyu; King, David L.

    2013-06-19

    Systems comprising of multiple sorbent and catalytic beds have been developed for the warm syngas cleanup of coal- and biomass-derived syngas. Tailored specifically for biomass application the process described here consists of six primary unit operations: 1) Na2CO3 bed for HCl removal, 2) two regenerable ZnO beds for bulk H2S removal, 3) ZnO bed for H2S polishing, 4) NiCu/SBA-16 sorbent for trace metal (e.g. AsH3) removal, 5) steam reforming catalyst bed for tars and light hydrocarbons reformation and NH3 decomposition, and a 6) Cu-based LT-WGS catalyst bed. Simulated biomass-derived syngas containing a multitude of inorganic contaminants (H2S, AsH3, HCl, and NH3) and hydrocarbon additives (methane, ethylene, benzene, and naphthalene) was used to demonstrate process effectiveness. The efficiency of the process was demonstrated for a period of 175 hours, during which no signs of deactivation were observed. Post-run analysis revealed small levels of sulfur slipped through the sorbent bed train to the two downstream catalytic beds. Future improvements could be made to the trace metal polishing sorbent to ensure complete inorganic contaminant removal (to low ppb level) prior to the catalytic steps. However, dual, regenerating ZnO beds were effective for continuous removal for the vast majority of the sulfur present in the feed gas. The process was effective for complete AsH3 and HCl removal. The steam reforming catalyst completely reformed all the hydrocarbons present in the feed (methane, ethylene, benzene, and naphthalene) to additional syngas. However, post-run evaluation, under kinetically-controlled conditions, indicates deactivation of the steam reforming catalyst. Spent material characterization suggests this is attributed, in part, to coke formation, likely due to the presence of benzene and/or naphthalene in the feed. Future adaptation of this technology may require dual, regenerable steam reformers. The process and materials described in this report hold promise for a warm cleanup of a variety of contaminant species within warm syngas.

  4. Parametric Optimization of the MEO Process for Treatment of Mixed Waste Residues

    SciTech Connect (OSTI)

    Cournoyer, M.E.; Smith, W.H.

    1999-02-28

    A series of bench-scale experiments were conducted to determine the optimum reaction conditions for destruction of styrene-divinyl benzene based cation resin and methylene chloride by the mediated electrochemical oxidation (MEO) process. Reaction parameters examined include choice of electron transfer mediator, reaction temperature and solvent system. For the cation exchange resins, maximum destruction efficiencies were obtained using cerium (IV) as mediator in nitric acid at a temperature of 70 C. Reasonable efficiencies were also realized with silver(II) and cobalt (III) at ambient temperature in the same solvent. Use of sulfuric acid as the solvent yielded much lower efficiencies under equivalent conditions. Methylene chloride was found to react only with silver (II) at ambient temperature in nitric acid media, cobalt (III) and cerium (IV) were totally ineffective. These results demonstrate a need to perform bench-scale experiments to determine optimum operating conditions for each organic substrate targeted for treatment by the MEO process.

  5. Soluble polyacetylenic and polyaromatic polymers and method of mking the same

    DOE Patents [OSTI]

    Aldissi, M.; Liepins, R.

    1983-12-16

    A soluble polyene polymer and a method of making the same are disclosed. The polymer is of the class suitable for doping to produce an electrically conductive polymer. The method is generally applicable to acetylenic and aromatic monomers, proven examples of which include acetylene, benzene, anthracene and napthalene. In accordance with the method, the monomer is dissolved in arsenic trifluoride. Arsenic pentafluoride is then introduced into the solution to induce polymerization by what is speculated to be an ionic polymerization reaction. The resulting polymer differs from other polyene polymers in that it is soluble in common organic solvents, and further in that it can be melted without undergoing decomposition, thereby rendering it particularly suitable for processing to form various polymeric articles.

  6. Method of making soluble polyacetylenic and polyaromatic polymers

    DOE Patents [OSTI]

    Aldissi, Mahmoud; Liepins, Raimond

    1985-01-01

    A soluble polyene polymer and a method of making the same are disclosed. The polymer is of the class suitable for doping to produce an electrically conductive polymer. The method is generally applicable to acetylenic and aromatic monomers, proven examples of which include acetylene, benzene, anthracene and napthalene. In accordance with the method, the monomer is dissolved in arsenic trifluoride. Arsenic pentafluoride is then introduced into the solution to induce polymerization by what is speculated to be an ionic polymerization reaction. The resulting polymer differs from other polyene polymers in that it is soluble in common organic solvents, and further in that it can be melted without undergoing decomposition, thereby rendering it particularly suitable for processing to form various polymeric articles.

  7. Radical Compatibility with Nonaqueous Electrolytes and Its Impact on an All-Organic Redox Flow Battery

    SciTech Connect (OSTI)

    Wei, Xiaoliang; Xu, Wu; Huang, Jinhua; Zhang, Lu; Walter, Eric D.; Lawrence, Chad W.; Vijayakumar, M.; Henderson, Wesley A.; Liu, Tianbiao L.; Cosimbescu, Lelia; Li, Bin; Sprenkle, Vincent L.; Wang, Wei

    2015-07-20

    Nonaqueous redox flow batteries hold the promise to achieve higher energy density ascribed to the broader voltage window than their aqueous counterparts, but their current performance is limited by low redox material concentration, poor cell efficiency, and inferior cycling stability. We report a new nonaqueous total-organic flow battery based on high concentrations of 9-fluorenone as negative and 2,5-di-tert-butyl-1-methoxy-4-[2’-methoxyethoxy]benzene as positive redox materials. The supporting electrolytes are found to greatly affect the cycling stability of flow cells through varying chemical stabilities of the charged radical species, especially the 9-fluorenone radical anions, as confirmed by electron spin resonance. Such an electrolyte optimization sheds light on mechanistic understandings of capacity fading in flow batteries employing organic radical-based redox materials and demonstrates that rational design of supporting electrolyte is vital for stable cyclability.

  8. Elaboration of m-cresol polyamide12/ polyaniline composite films for antistatic applications

    SciTech Connect (OSTI)

    Mezdour, D.; Tabellout, M.; Bardeau, J.-F; Sahli, S.

    2013-12-16

    The present work deals with the preparation of transparent antistatic films from an extreme dilution of an intrinsically conducting polymer (ICP) with not coloured polymers. Our approach is based on the chemical polymerization of a very thin layer of Polyaniline (PANI) around particles of an insulating polymer (PA12). Films were obtained by dissolving the synthesized core-shell particles in m-Cresol. The electric property and structure relationships were investigated by using dielectric relaxation spectroscopy, X-ray diffraction and micro-Raman spectroscopy. Composite films exhibited a well established dc conductivity over all the frequency range for 10 wt. % of PANI concentration related to the conductive properties of the PANI clusters. X-ray diffraction data show broader and lower intensity of PA12 peaks when increasing PANI content, probably due to the additional doping effect of m- cresol. The doping of PA12/PANI films with Dodecyl benzene sulfonic acid (DBSA) was unequivocally verified by Raman spectroscopy.

  9. Low Temperature Chemical Vapor Deposition Of Thin Film Magnets

    DOE Patents [OSTI]

    Miller, Joel S.; Pokhodnya, Kostyantyn I.

    2003-12-09

    A thin-film magnet formed from a gas-phase reaction of tetracyanoetheylene (TCNE) OR (TCNQ), 7,7,8,8-tetracyano-P-quinodimethane, and a vanadium-containing compound such as vanadium hexcarbonyl (V(CO).sub.6) and bis(benzene)vanalium (V(C.sub.6 H.sub.6).sub.2) and a process of forming a magnetic thin film upon at least one substrate by chemical vapor deposition (CVD) at a process temperature not exceeding approximately 90.degree. C. and in the absence of a solvent. The magnetic thin film is particularly suitable for being disposed upon rigid or flexible substrates at temperatures in the range of 40.degree. C. and 70.degree. C. The present invention exhibits air-stable characteristics and qualities and is particularly suitable for providing being disposed upon a wide variety of substrates.

  10. RECOVERY OF PROTACTINIUM

    DOE Patents [OSTI]

    Kraus, K.A.; Moore, G.E.

    1959-02-01

    A process is presented for the separation of protactinium values from an aqueous solution containing Pa and Th values comprising establishing in the solution a HCl concentration of from 4 to 11 molar, contacting the resulting solution with an anion-exchange adsorbent, such as a polystyrene divinyl benzene polymer with quatenary amines as the active exchange group, to effect the adsorption of Pa values upon the adsorbent while leaving Th values in the solution, and then washlng the separated Pa bearing adsorbent with an aqueous solution of HCl of less than 4M to exclusively elute Pa values from the adsorbent. If hexavalent U values are contained in the original solution thcy are adsorbed on the resin together with Pa. A separation is offected chromatographically by percolating the resin with aqueous HCl.

  11. High temperature chemically resistant polymer concrete

    DOE Patents [OSTI]

    Sugama, T.; Kukacka, L.E.

    High temperature chemically resistant, non-aqueous polymer concrete composites consist of about 12 to 20% by weight of a water-insoluble polymer binder. The binder is polymerized in situ from a liquid vinyl-type monomer or mixture of vinyl containing monomers such as triallylcyanurate, styrene, acrylonitrile, acrylamide, methacrylamide, methyl-methacrylate, trimethylolpropane trimethacrylate and divinyl benzene. About 5 to 40% by weight of a reactive inorganic filler selected from the group consisting of tricalcium silicate and dicalcium silicate and mixtures containing less than 2% free lime, and about 48 to 83% by weight of silica sand/ and a free radical initiator such as di-tert-butyl peroxide, azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide, other orgaic peroxides and combinations to initiate polymerization of the monomer in the presence of the inorganic filers are used.

  12. A new class of electrochemically and thermally stable lithium salts for lithium battery electrolytes. 3: Synthesis and properties of some lithium organoborates

    SciTech Connect (OSTI)

    Barthel, J.; Buestrich, R.; Carl, E.; Gores, H.J.

    1996-11-01

    Synthesis, analysis, and purification of new lithium salts for lithium batteries, lithium bis[tetrafluoro-1,2-benzene-diolato(2-)-O,O{prime}]borate and lithium bis[2,3-naphthalenediolato(2-)-O,O{prime}]borate are described, and the results of electrochemical studies of these salts and of lithium bis[3-fluoro-1,2-benzenediolato(2-)-O,O{prime}]borate, in propylene carbonate are reported. The effect of the electron-withdrawing substituent fluorine results in an increase of the electrochemical window by 0.1 V/fluorine per one chelate ligand. The slope, which can be calculated from the linear correlation of the highest occupied molecular orbital energies with anodic oxidation potentials is {minus}3.0 eV/V, a value equal to that known for aryl borates and fluoroaryl borates.

  13. Equation of motion coupled cluster methods for electron attachment and ionization potential in polyacenes

    SciTech Connect (OSTI)

    Bhaskaran-Nair, Kiran; Kowalski, Karol; Jarrell, Mark; Moreno, Juana; Shelton, William A.

    2015-11-05

    Polyacenes have attracted considerable attention due to their use in organic based optoelectronic materials. Polyacenes are polycyclic aromatic hydrocarbons composed of fused benzene rings. Key to understanding and design of new functional materials is an understanding of their excited state properties starting with their electron affinity (EA) and ionization potential (IP). We have developed a highly accurate and com- putationally e*fficient EA/IP equation of motion coupled cluster singles and doubles (EA/IP-EOMCCSD) method that is capable of treating large systems and large basis set. In this study we employ the EA/IP-EOMCCSD method to calculate the electron affinity and ionization potential of naphthalene, anthracene, tetracene, pentacene, hex- acene and heptacene. We have compared our results with other previous theoretical studies and experimental data. Our EA/IP results are in very good agreement with experiment and when compared with the other theoretical investigations our results represent the most accurate calculations as compared to experiment.

  14. Substantially isotactic, linear, alternating copolymers of carbon monoxide and an olefin

    DOE Patents [OSTI]

    Sen, A.; Jiang, Z.

    1996-05-28

    The compound, [Pd(Me-DUPHOS)(MeCN){sub 2}](BF{sub 4}){sub 2}, [Me-DUPHOS: 1,2-bis(2,5-dimethylphospholano)benzene] is an effective catalyst for the highly enantioselective, alternating copolymerization of olefins, such as aliphatic {alpha}-olefins, with carbon monoxide to form optically active, isotactic polymers which can serve as excellent starting materials for the synthesis of other classes of chiral polymers. For example, the complete reduction of a propylene-carbon monoxide copolymer resulted in the formation of a novel, optically active poly(1,4-alcohol). Also, the previously described catalyst is a catalyst for the novel alternating isomerization cooligomerization of 2-butene with carbon monoxide to form optically active, isotactic poly(1,5-ketone).

  15. Ethylene plant commissioned at Corpus Christi

    SciTech Connect (OSTI)

    Not Available

    1984-01-01

    Ethylene Plant Commissioned at Corpus Christi. Corpus Christi Petrochemical Co. has commissioned its $600 million ethylene plant at Corpus Christi, Tex. Plant capacities include 1.2 billion lb/yr of ethylene, 560 million lb/yr of propylene, 400 million lb/yr of crude butadiene mixture, 60 million gal of benzene, 45 million gal of gasoline blending components, and 50 million gal of fuel oils. The ethylene and propylene will be transported by pipeline to Houston for further processing. At the Corpus Christi facilities, process pressures range from full vacuum to 1800 psig, and process temperatures range from -260/sup 0/ to +1600/sup 0/F. The plant uses gas oil and naphtha as feedstock, but also has some flexibility to use ethane or LPG as feedstock. Stone and Webster Engineering Corp. engineered and Brown and Root Inc. built the plant.

  16. Process for the production of ethylene and other hydrocarbons from coal

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.

    1982-02-16

    A process is claimed for the production of substantial amounts of ethylene and other hydrocarbon compounds, such as benzene from coal. Coal is reacted with methane at a temperature in the approximate range of 500/sup 0/C to 1100/sup 0/C at a partial pressure less than about 200 psig for a period of less than 10 seconds, and preferably at a temperature of approximately 850/sup 0/C, and a partial pressure of 50 psig for a period of approximately 2 seconds. Ethylene and other hydrocarbon compounds may be separated from the product stream so produced, and the methane recycled for further production of ethylene. In another embodiment, other compounds produced, such as by-product tars, may be burned to heat the recycled methane.

  17. Process to convert biomass and refuse derived fuel to ethers and/or alcohols

    DOE Patents [OSTI]

    Diebold, James P.; Scahill, John W.; Chum, Helena L.; Evans, Robert J.; Rejai, Bahman; Bain, Richard L.; Overend, Ralph P.

    1996-01-01

    A process for conversion of a feedstock selected from the group consisting of biomass and refuse derived fuel (RDF) to provide reformulated gasoline components comprising a substantial amount of materials selected from the group consisting of ethers, alcohols, or mixtures thereof, comprising: drying said feedstock; subjecting said dried feedstock to fast pyrolysis using a vortex reactor or other means; catalytically cracking vapors resulting from said pyrolysis using a zeolite catalyst; condensing any aromatic byproduct fraction; catalytically alkylating any benzene present in said vapors after condensation; catalytically oligomerizing any remaining ethylene and propylene to higher olefins; isomerizing said olefins to reactive iso-olefins; and catalytically reacting said iso-olefins with an alcohol to form ethers or with water to form alcohols.

  18. Process to convert biomass and refuse derived fuel to ethers and/or alcohols

    DOE Patents [OSTI]

    Diebold, J.P.; Scahill, J.W.; Chum, H.L.; Evans, R.J.; Rejai, B.; Bain, R.L.; Overend, R.P.

    1996-04-02

    A process is described for conversion of a feedstock selected from the group consisting of biomass and refuse derived fuel (RDF) to provide reformulated gasoline components comprising a substantial amount of materials selected from the group consisting of ethers, alcohols, or mixtures thereof, comprising: drying said feedstock; subjecting said dried feedstock to fast pyrolysis using a vortex reactor or other means; catalytically cracking vapors resulting from said pyrolysis using a zeolite catalyst; condensing any aromatic byproduct fraction; catalytically alkylating any benzene present in said vapors after condensation; catalytically oligomerizing any remaining ethylene and propylene to higher olefins; isomerizing said olefins to reactive iso-olefins; and catalytically reacting said iso-olefins with an alcohol to form ethers or with water to form alcohols. 35 figs.

  19. Polymer concrete composites for the production of high strength pipe and linings in high temperature corrosive environments

    DOE Patents [OSTI]

    Zeldin, A.; Carciello, N.; Fontana, J.; Kukacka, L.

    High temperature corrosive resistant, non-aqueous polymer concrete composites are described. They comprise about 12 to 20% by weight of a water-insoluble polymer binder polymerized in situ from a liquid monomer mixture consisting essentially of about 40 to 70% by weight of styrene, about 25 to 45% by weight acrylonitrile and about 2.5 to 7.5% by weight acrylamide or methacrylamide and about 1 to 10% by weight of a crosslinking agent. This agent is selected from the group consisting of trimethylolpropane trimethacrylate and divinyl benzene; and about 80 to 88% by weight of an inert inorganic filler system containing silica sand and portland cement, and optionally Fe/sub 2/O/sub 3/ or carbon black or mica. A free radical initiator such as di-tert-butyl peroxide, azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide, other organic peroxides and combinations thereof to initiate crosspolymerization of the monomer mixture in the presence of said inorganic filler.

  20. High temperature concrete composites containing organosiloxane crosslinked copolymers

    DOE Patents [OSTI]

    Zeldin, A.; Carciello, N.; Kukacka, L.; Fontana, J.

    High temperature polymer concrete composites comprising about 10 to 30% by weight of a liquid monomer mixture is described. It consists essentially of an organosiloxane polymer crosslinked with an olefinically unsaturated monomer selected from the group consisting of styrene, methyl methacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, n-phenylmalimide, divinyl benzene and mixtures thereof. About 70 to 90% by weight of an inert inorganic filler system containing silica sand and portland cement, Fe/sub 2/O/sub 3/, carbon black or mixtures thereof. Optionally a free radical initiator such as di-tert-butyl peroxide, azobisisobyutyronitrile, benzoyl peroxide, lauryl peroxide and other organic peroxides are used to initiate crosspolymerization of the monomer mixture in the presence of the inorganic filler.

  1. Nano-electromechanical rotation of graphene and giant enhancement in dielectric anisotropy in a liquid crystal

    SciTech Connect (OSTI)

    Basu, Rajratan Kinnamon, Daniel; Garvey, Alfred

    2015-05-18

    A nematic liquid crystal (LC) is doped with dilute concentrations of pristine monolayer graphene (GP) flakes, and the LC + GP hybrids are found to exhibit a dramatic increase in the dielectric anisotropy. Electric field-dependent conductance studies reveal that the graphene flakes follow the nematic director that mechanically rotates on increasing an applied electric field. Further studies show that the ?–? electron stacking, between the graphene's honeycomb structure and the LC's benzene rings, stabilizes pseudo-nematic domains that collectively amplify the dielectric anisotropy by improving the orientational order parameter in the nematic phase. These anisotropic domains interact with the external electric field, resulting in a nonzero dielectric anisotropy in the isotropic phase as well. The enhancement in dielectric anisotropy, due to the LC–graphene coupling, is found to have subsequent positive impacts on the LC's orientational threshold field and elasticity that allows the nematic director to respond quicker on switching the electric field off.

  2. Substantially isotactic, linear, alternating copolymers of carbon monoxide and an olefin

    DOE Patents [OSTI]

    Sen, Ayusman; Jiang, Zhaozhong

    1996-01-01

    The compound, [Pd(Me-DUPHOS)(MeCN).sub.2 ](BF.sub.4).sub.2, [Me-DUPHOS: 1,2-bis(2,5-dimethylphospholano)benzene] is an effective catalyst for the highly enantioselective, alternating copolymerization of olefins, such as aliphatic .alpha.-olefins, with carbon monoxide to form optically active, isotactic polymers which can serve as excellent starting materials for the synthesis of other classes of chiral polymers. For example, the complete reduction of a propylene-carbon monoxide copolymer resulted in the formation of a novel, optically active poly(1,4-alcohol). Also, the previously described catalyst is a catalyst for the novel alternating isomerization cooligomerization of 2-butene with carbon monoxide to form optically active, isotactic poly(1,5-ketone)

  3. Tuning the thickness of electrochemically grafted layers in large area molecular junctions

    SciTech Connect (OSTI)

    Fluteau, T.; Bessis, C.; Barraud, C. Della Rocca, M. L.; Lafarge, P.; Martin, P.; Lacroix, J.-C.

    2014-09-21

    We have investigated the thickness, the surface roughness, and the transport properties of oligo(1-(2-bisthienyl)benzene) (BTB) thin films grafted on evaporated Au electrodes, thanks to a diazonium-based electro-reduction process. The thickness of the organic film is tuned by varying the number of electrochemical cycles during the growth process. Atomic force microscopy measurements reveal the evolution of the thickness in the range of 2–27 nm. Its variation displays a linear dependence with the number of cycles followed by a saturation attributed to the insulating behavior of the organic films. Both ultrathin (2 nm) and thin (12 and 27 nm) large area BTB-based junctions have then been fabricated using standard CMOS processes and finally electrically characterized. The electronic responses are fully consistent with a tunneling barrier in case of ultrathin BTB film whereas a pronounced rectifying behavior is reported for thicker molecular films.

  4. High temperature concrete composites containing organosiloxane crosslinked copolymers

    DOE Patents [OSTI]

    Zeldin, Arkady; Carciello, Neal; Kukacka, Lawrence; Fontana, Jack

    1980-01-01

    This invention relates to high temperature polymer concrete composites comprising about 10-30% by weight of a liquid monomer mixture consisting essentially of an organosiloxane polymer crosslinked with an olefinically unsaturated monomer selected from the group consisting of styrene, methyl methacrylate, trimethylolpropane trimethacrylate, triallyl cyanurate, n-phenylmalimide, divinyl benzene and mixtures theroef; and about 70-90% by weight of an inert inorganic filler system containing silica sand and preferably a member selected from the group consisting of portland cement, Fe.sub.2 O.sub.3, carbon black and mixtures thereof; and optionally a free radical initiator such as di-tert-butyl peroxide, azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide and other organic peroxides to initiate crosspolymerization of the monomer mixture in the presence of the inorganic filler.

  5. Temperature dependence of photoluminescence properties in a thermally activated delayed fluorescence emitter

    SciTech Connect (OSTI)

    Niwa, Akitsugu; Kobayashi, Takashi Nagase, Takashi; Naito, Hiroyoshi; Goushi, Kenichi; Adachi, Chihaya

    2014-05-26

    Using steady-state and time-resolved photoluminescence (PL) spectroscopy, we have investigated the temperature dependence of PL properties of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyano-benzene (4CzIPN), which have a small energy gap between its singlet and triplet excited states and thus exhibits efficient thermally activated delayed fluorescence [H. Uoyama et al., Nature 492, 235 (2012)]. Below around 100?K, PL quantum efficiency of 4CzIPN thin films is largely suppressed and strong photoexcitation intensity dependence appears. These features can be explained by using rate equations for the densities of singlet and triplet excited states considering a triplet-triplet annihilation process.

  6. THE RICH CIRCUMSTELLAR CHEMISTRY OF SMP LMC 11

    SciTech Connect (OSTI)

    Malek, S. E.; Cami, J.; Bernard-Salas, J. E-mail: jcami@uwo.ca

    2012-01-01

    Carbon-rich evolved stars from the asymptotic giant branch to the planetary nebula phase are characterized by a rich and complex carbon chemistry in their circumstellar envelopes. A peculiar object is the preplanetary nebula SMP LMC 11, whose Spitzer Infrared Spectrograph spectrum shows remarkable and diverse molecular absorption bands. To study how the molecular composition in this object compares to our current understanding of circumstellar carbon chemistry, we modeled this molecular absorption. We find high abundances for a number of molecules, perhaps most notably benzene. We also confirm the presence of propyne (CH{sub 3}C{sub 2}H) in this spectrum. Of all the cyanopolyynes, only HC{sub 3}N is evident; we can detect at best a marginal presence of HCN. From comparisons to various chemical models, we can conclude that SMP LMC 11 must have an unusual circumstellar environment (a torus rather than an outflow).

  7. Mesoporous organosilica nanotubes containing a chelating ligand in their walls

    SciTech Connect (OSTI)

    Liu, Xiao; Goto, Yasutomo; Maegawa, Yoshifumi; Inagaki, Shinji

    2014-11-01

    We report the synthesis of organosilica nanotubes containing 2,2?-bipyridine chelating ligands within their walls, employing a single-micelle-templating method. These nanotubes have an average pore diameter of 7.8 nm and lengths of several hundred nanometers. UV-vis absorption spectra and scanning transmission electron microscopy observations of immobilized nanotubes with an iridium complex on the bipyridine ligands showed that the 2,2?-bipyridine groups were homogeneously distributed in the benzene-silica walls. The iridium complex, thus, immobilized on the nanotubes exhibited efficient catalytic activity for water oxidation using Ce{sup 4+}, due to the ready access of reactants to the active sites in the nanotubes.

  8. Reduction of Aromatic Hydrocarbons by Zero-Valent Iron and Palladium Catalyst

    SciTech Connect (OSTI)

    Kim, Young-Hun; Shin, Won Sik; Ko, Seok-Oh; Kim, Myung-Chul

    2004-03-31

    Permeable reactive barrier (PRB) is an alternative technology for soil and groundwater remediation. Zero valent iron, which is the most popular PRB material, is only applicable to halogenated aliphatic organics and some heavy metals. The objective of this study was to investigate reductive dechlorination of halogenated compounds and reduction of non-halogenated aromatic hydrocarbons using zero valent metals (ZVMs) and catalysts as reactive materials for PRBs. A group of small aromatic hydrocarbons such as monochlorophenols, phenol and benzene were readily reduced with palladium catalyst and zero valent iron. Poly-aromatic hydrocarbons (PAHs) were also tested with the catalysts and zero valent metal combinations. The aromatic rings were reduced and partly reduced PAHs were found as the daughter compounds. The current study demonstrates reduction of aromatic compounds by ZVMs and modified catalysts and implicates that PRB is applicable not only for halogenated organic compounds but nonhalogenated aromatic compounds such as PAHs.

  9. Dynamic simulation of the in-tank precipitation process

    SciTech Connect (OSTI)

    Hang, T.; Shanahan, K.L.; Gregory, M.V.; Walker, D.D.

    1993-12-31

    As part of the High-Level Waste Tank Farm at the Savannah River Site (SRS), the In-Tank Precipitation (ITP) facility was designed to decontaminate the radioactive waste supernate by removing cesium as precipitated cesium tetraphenylborate. A dynamic computer model of the ITP process was developed using SPEEDUP{sup TM} software to provide guidance in the areas of operation and production forecast, production scheduling, safety, air emission, and process improvements. The model performs material balance calculations in all phase (solid, liquid, and gas) for 50 key chemical constituents to account for inventory accumulation, depletion, and dilution. Calculations include precipitation, benzene radiolytic reactions, evaporation, dissolution, adsorption, filtration, and stripping. To control the ITP batch operation a customized FORTRAN program was generated and linked to SPEEDUP{sup TM} simulation This paper summarizes the model development and initial results of the simulation study.

  10. A divergent route to core- and peripherally functionalized diazacoronenes that act as colorimetric and fluorescence proton sensors

    SciTech Connect (OSTI)

    He, Bo; Dai, Jing; Zherebetskyy, Danylo; Chen, Teresa L.; Zhang, Benjamin A.; Teat, Simon J.; Zhang, Qichun; Wang, Linwang; Liu, Yi

    2015-03-31

    Combining core annulation and peripheral group modification, we have demonstrated a divergent synthesis of a family of highly functionalized coronene derivatives from a readily accessible dichlorodiazaperylene intermediate. Various reactions, such as aromatic nucleophilic substitution, Kumada coupling and Suzuki coupling proceed effectively on ?-positions of the pyridine sites, giving rise to alkoxy, thioalkyl, alkyl or aryl substituted polycyclic aromatic hydrocarbons. In addition to peripheral group modulation, the aromatic core structures can be altered by annulation with thiophene or benzene ring systems. Corresponding single crystal X-ray diffraction and optical studies indicate that the heteroatom linkages not only impact the solid state packing, but also significantly influence the optoelectronic properties. Moreover, these azacoronene derivatives display significant acid-induced spectroscopic changes, suggesting their great potential as colorimetric and fluorescence proton sensors.

  11. A divergent route to core- and peripherally functionalized diazacoronenes that act as colorimetric and fluorescence proton sensors

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    He, Bo; Dai, Jing; Zherebetskyy, Danylo; Chen, Teresa L.; Zhang, Benjamin A.; Teat, Simon J.; Zhang, Qichun; Wang, Linwang; Liu, Yi

    2015-03-31

    Combining core annulation and peripheral group modification, we have demonstrated a divergent synthesis of a family of highly functionalized coronene derivatives from a readily accessible dichlorodiazaperylene intermediate. Various reactions, such as aromatic nucleophilic substitution, Kumada coupling and Suzuki coupling proceed effectively on α-positions of the pyridine sites, giving rise to alkoxy, thioalkyl, alkyl or aryl substituted polycyclic aromatic hydrocarbons. In addition to peripheral group modulation, the aromatic core structures can be altered by annulation with thiophene or benzene ring systems. Corresponding single crystal X-ray diffraction and optical studies indicate that the heteroatom linkages not only impact the solid state packing,more » but also significantly influence the optoelectronic properties. Moreover, these azacoronene derivatives display significant acid-induced spectroscopic changes, suggesting their great potential as colorimetric and fluorescence proton sensors.« less

  12. Use of Chelex-100 for selectively removing Y-90 from its parent Sr-90

    DOE Patents [OSTI]

    Huntley, M.W.

    1996-02-27

    A method for selectively removing yttrium-90 from its parent strontium-90 contained in an environmental sample includes loading the sample onto a column containing a chelating ion-exchange resin capable of retaining yttrium-90; washing the column with a solution capable of removing strontium, calcium, and other contaminants from the yttrium-90 fraction retained on the column; removing excess acetate salts from the column; eluting yttrium-90 solution from the column and adjusting the pH of this solution to about 2.7; filtering the yttrium-90 solution and weighing this solution for gravimetric yield; and, counting the yttrium-90 containing solution with a radiological counter for a time sufficient to achieve the statistical accuracy desired. It is preferred that the chelating ion-exchange resin is a ligand having the chemical name iminodiacetic acid mounted on a divinyl benzene substrate, converted from sodium form to ammonia form.

  13. Use of Chelex-100 for selectively removing Y-90 from its parent Sr-90

    DOE Patents [OSTI]

    Huntley, Mark W.

    1996-01-01

    A method for selectively removing yttrium-90 from its parent strontium-90 contained in an environmental sample includes loading the sample onto a column containing a chelating ion-exchange resin capable of retaining yttrium-90; washing the column with a solution capable of removing strontium, calcium, and other contaminants from the yttrium-90 fraction retained on the column; removing excess acetate salts from the column; eluting yttrium-90 solution from the column and adjusting the pH of this solution to about 2.7; filtering the yttrium-90 solution and weighing this solution for gravimetric yield; and, counting the yttrium-90 containing solution with a radiological counter for a time sufficient to achieve the statistical accuracy desired. It is preferred that the chelating ion-exchange resin is a bidente ligand having the chemical name iminodiacetic acid mounted on a divinyl benzene substrate, converted from sodium form to ammonia form.

  14. Flash pyrolysis of biomass with reactive and non-reactive gases

    SciTech Connect (OSTI)

    Steinberg, M.; Fallon, P.T.

    1982-06-01

    The rapid or flash pyrolysis of wood biomass is being studied in a 1'' downflow entrained tubular reactor with a capacity of approximately 1 lb/hr of wood. The process chemistry data is being obtained with the view of building a data base and ascertaining the value of producing synthetic fuels and chemical feedstocks by the flash pyrolysis method. Data is being obtained on the effect of non-reactive pyrolyzing gases and the effect of reactive gases, hydrogen for the flash hydropyrolysis of wood and methane for flash methanolysis of wood. Preliminary process design and analysis has been made. The yield of ethylene and benzene is especially attractive for the production of chemical feedstocks from the reaction of methane and wood in a flash methanolysis process.

  15. Applications of organo-calcium chemistry to control contaminant aromatic hydrocarbons in advanced coal gasification processes: Final technical progress report

    SciTech Connect (OSTI)

    Longwall, J.P.; Chang, C.C.S.; Lai, C.K.S.; Chen, P.; Hajaligol, M.R.; Peters, W.A.

    1988-09-01

    The broad goal of this contract was to provide quantitative understanding of the thermal reactions of aromatics contaminants with calcium oxide under conditions pertinent to their in situ or out-board reduction or elimination from advanced coal gasification process and waste streams. Specific objectives were formalized into the following four tasks: cracking of fresh coal pyrolysis tar, benzene cracking, CaO deactivation behavior, and preliminary economic implications. The approach primarily involved laboratory scale measurements of rates and extents of feed conversion, and of quality indices or compositions of the resulting products, when pure aromatic compounds or newly formed coal pyrolysis tars undergo controlled extents of thermal treatment with CaO of known preparation history. 70 refs., 54 figs., 7 tabs.

  16. SEPARATION PROCESS FOR ZIRCONIUM AND COMPOUNDS THEREOF

    DOE Patents [OSTI]

    Crandall, H.W.; Thomas, J.R.

    1959-06-30

    The separation of zirconium from columbium, rare earths, yttrium and the alkaline earth metals, such mixtures of elements occurring in zirconium ores or neutron irradiated uranium is described. According to the invention a suitable separation of zirconium from a one normal acidic aqueous solution containing salts, nitrates for example, of tetravalent zirconium, pentavalent columbium, yttrium, rare earths in the trivalent state and alkaline earths can be obtained by contacting the aqueous solution with a fluorinated beta diketonc alone or in an organic solvent solution, such as benzene, to form a zirconium chelate compound. When the organic solvent is present the zirconium chelate compound is directly extracted; otherwise it is separated by filtration. The zirconium may be recovered from contacting the organic solvent solution containing the chelated compound by back extraction with either an aqueous hydrofluoric acid or an oxalic acid solution.

  17. Studies of ground-state dynamics in isolated species by ionization-detected stimulated Raman techniques

    SciTech Connect (OSTI)

    Felker, P.M.

    1993-12-01

    First, the author aims to develop methods of nonlinear Raman spectroscopy for application in studies of sparse samples. Second, the author wishes to apply such methods to structural and dynamical studies of species (molecules, complexes, and clusters) in supersonic molecular beams. In the past year, the author has made progress in several areas. The first pertains to the application of mass-selective ionization-detected stimulated Raman spectroscopies (IDSRS) to the size-specific vibrational spectroscopy of solute-solvent{sub n} clusters. The second involves the application of IDSRS methods to studies of jet-cooled benzene clusters. The third pertains to the use of IDSRS methods in the study of intermolecular vibrational transitions in van der Waals complexes.

  18. Analytic cubic and quartic force fields using density-functional theory

    SciTech Connect (OSTI)

    Ringholm, Magnus; Gao, Bin; Thorvaldsen, Andreas J.; Ruud, Kenneth; Jonsson, Dan; High Performance Computing Group, University of Tromsø—The Arctic University of Norway, 9037 Tromsø ; Bast, Radovan; Ekström, Ulf; Helgaker, Trygve

    2014-01-21

    We present the first analytic implementation of cubic and quartic force constants at the level of Kohn–Sham density-functional theory. The implementation is based on an open-ended formalism for the evaluation of energy derivatives in an atomic-orbital basis. The implementation relies on the availability of open-ended codes for evaluation of one- and two-electron integrals differentiated with respect to nuclear displacements as well as automatic differentiation of the exchange–correlation kernels. We use generalized second-order vibrational perturbation theory to calculate the fundamental frequencies of methane, ethane, benzene, and aniline, comparing B3LYP, BLYP, and Hartree–Fock results. The Hartree–Fock anharmonic corrections agree well with the B3LYP corrections when calculated at the B3LYP geometry and from B3LYP normal coordinates, suggesting that the inclusion of electron correlation is not essential for the reliable calculation of cubic and quartic force constants.

  19. Use and value of reactive lignin. Final report

    SciTech Connect (OSTI)

    Frank, M.E.; Mednick, R.L.; Stern, K.M.

    1988-03-01

    New York State has ample reserves of wood that are not suitable for lumber nor paper making. The Energy Authority has several research projects to utilize wood for the production of fuels and energy intensive chemicals. The Energy Authority and Chem Systems set out to characterize the market potential for lignins derived as by-products of wood-to-ethanol processes. Based on these analyses and subsequent ranking of the potential applications, three end uses (Phenol-Formaldehyde resin adhesives, carbon black substitutes and diesel fuel cetane enhancers) were characterized as having a high potential of commercial success. Epoxies were characterized as having a low potential. The prospects of the remaining end uses (activated carbon replacements, polyurethanes, dietary adsorbents, phenol/benzene and asphalt extenders) were classified as intermediate, along with those of the Urea-Formaldehyde resin portion of the adhesive market.

  20. Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

    DOE Patents [OSTI]

    Vijayan, S.; Wong, C.F.; Buckley, L.P.

    1994-11-22

    In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved. 1 fig.

  1. Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

    DOE Patents [OSTI]

    Vijayan, Sivaraman; Wong, Chi F.; Buckley, Leo P.

    1994-01-01

    In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved.

  2. PROCESS FOR PRODUCING ALKYL ORTHOPHOSPHORIC ACID EXTRACTANTS

    DOE Patents [OSTI]

    Grinstead, R.R.

    1962-01-23

    A process is given for producing superior alkyl orthophosphoric acid extractants for use in solvent extraction methods to recover and purify various metals such as uranium and vanadium. The process comprises slurrying P/sub 2/O/ sub 5/ in a solvent diluent such as kerosene, benzene, isopropyl ether, and the like. An alipbatic alcohol having from nine to seventeen carbon atoms, and w- hcrein ihc OH group is situated inward of the terminal carbon atoms, is added to the slurry while the reaction temperature is mainiained below 60 deg C. The alcohol is added in the mole ratio of about 2 to l, alcohol to P/sub 2/O/sub 5/. A pyrophosphate reaotion product is formed in the slurry-alcohol mixture. Subsequently, the pyrophosphate reaction product is hydrolyzed with dilute mineral acid to produce the desired alkyl orthophosphoric aeid extractant. The extraetant may then be separated and utilized in metal-recovery, solvent- extraction processes. (AEC)

  3. Experimental triplet and quadruplet fluctuation densities and spatial distribution function integrals for liquid mixtures

    SciTech Connect (OSTI)

    Ploetz, Elizabeth A.; Smith, Paul E.

    2015-03-07

    Kirkwood-Buff or Fluctuation Solution Theory can be used to provide experimental pair fluctuations, and/or integrals over the pair distribution functions, from experimental thermodynamic data on liquid mixtures. Here, this type of approach is used to provide triplet and quadruplet fluctuations, and the corresponding integrals over the triplet and quadruplet distribution functions, in a purely thermodynamic manner that avoids the use of structure factors. The approach is then applied to binary mixtures of water + methanol and benzene + methanol over the full composition range under ambient conditions. The observed correlations between the different species vary significantly with composition. The magnitude of the fluctuations and integrals appears to increase as the number of the most polar molecule involved in the fluctuation or integral also increases. A simple physical picture of the fluctuations is provided to help rationalize some of these variations.

  4. Core-Shell Diamond as a Support for Solid-Phase Extraction and High-Performance Liquid Chromatography

    SciTech Connect (OSTI)

    Saini, Gaurav; Jensen, David S.; Wiest, Landon A.; Vail, Michael A.; Dadson, Andrew; Lee, Milton L.; Shutthanandan, V.; Linford, Matthew R.

    2010-06-01

    We report the formation of core-shell diamond particles for solid phase extraction (SPE) and high performance liquid chromatography (HPLC) made by layer-by-layer (LbL) deposition. Their synthesis begins with the amine functionalization of microdiamond by its immersion in an aqueous solution of a primary amine-containing polymer (polyallylamine (PAAm)). The amine-terminated microdiamond is then immersed in an aqueous suspension of nanodiamond, which leads to adsorption of the nanodiamond. Alternating (self-limiting) immersions in the solutions of the amine-containing polymer and the suspension of nanodiamond are continued until the desired number of nanodiamond layers is formed around the microdiamond. Finally, the core-shell particles are cross-linked with 1,2,5,6-diepoxycyclooctane or reacted with 1,2-epoxyoctadecane. Layer-by-layer deposition of PAAm and nanodiamond is also studied on planar Si/SiO2 surfaces, which were characterized by SEM, Rutherford backscattering spectrometry (RBS) and nuclear reaction analysis (NRA). Core-shell particles are characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), environmental scanning electron microscopy (ESEM), and Brunauer Emmett Teller (BET) surface area and pore size measurements. Larger (ca. 50 ?m) core-shell diamond particles have much higher surface areas, and analyte loading capacities in SPE than nonporous solid diamond particles. Smaller (ca. 3 ?m), normal and reversed phase, core-shell diamond particles have been used for HPLC, with 36,300 plates per meter for mesitylene in a separation of benzene and alkyl benzenes on a C18 adsorbent, and 54,800 plates per meter for diazinon in a similar separation of two pesticides.

  5. Exploratory study of coal-conversion chemistry. Quarterly report, June 20, 1980-September 19, 1980. [Diphenylmethane, diphenyl ether

    SciTech Connect (OSTI)

    Not Available

    1981-03-04

    This report describes work accomplished under two task: Task A, Mechanism of Cleavage of Key Bond types Present in Coals, and Task B, Catalysis of Conversion in CO-H/sub 2/O Systems. Under Task A, we have made additional measurements of catalytic carbon-carbon and carbon-oxygen bond cleavage in coal-related diphenylmethane and diphenyl ether structures. The results provide further support for, but do not definitely confirm, the tentative conclusion that the highly effective iron oxide catalysts involves oxidation to radical cation species. The homogeneous scission of carbon-oxygen bonds in diphenyl ether structure has also been studied. In the Task B studies of CO-H/sub 2/O systems, we typically obtain 50% benzene-soluble product material from 20 min. reaction of beneficiated Illinois No. 6 coal. This conversion level is obtained with aqueous solutions either at a starting pH above 12.6 or in neutral solutions with water-soluble catalysts present. We have studied a number of catalysts, including the potassium or sodium salts of molybdate, chromate, manganate, and tungstate; all are effective in the 3000 to 6000 ppM range. A striking result is that sodium nitrate at 6000 ppM is as effective as the metal salts. We found that the nitrate was converted to ammonium ion; also, formate was detected in the product aqueous phase. Finally, we find that catalytic quantities of sodium formate in CO/H/sub 2/O at pH 7 are effective in the conversion. However, in a control run in N/sub 2//H/sub 2/O, with a quantity of sodium formate equivalent to twice the molar quantity of hydrogen transferred to the coal in a successful run, the coal was converted to a product totally insoluble in benzene and with a lower hydrogen content than the starting coal.

  6. Hidden Superlattice in Tl2(SC6H4S) and Tl2(SeC6H4Se) Solved from Powder X-ray Diffraction

    SciTech Connect (OSTI)

    K Stone; D Turner; M Singh; T Vaid; P Stephens

    2011-12-31

    The crystal structures of the isostructural title compounds poly[({mu}-benzene-1,4-dithiolato)dithallium], Tl{sub 2}(SC{sub 6}H{sub 4}S), and poly[({mu}-benzene-1,4-diselenolato)dithallium], Tl{sub 2}(SeC{sub 6}H{sub 4}Se), were solved by simulated annealing from high-resolution synchrotron X-ray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close non-bonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl-S or Tl-Se two-dimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a 'see-saw' shape, depending upon how many Tl-S or Tl-Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl{sup I} ions that interact through a closed-shell 'thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl-Tl distances of 3.49 and 3.58 {angstrom}, while in the selenium compound those Tl-Tl interactions are at 3.54 and 3.63 {angstrom}.

  7. The solvation radius of silicate melts based on the solubility of noble gases and scaled particle theory

    SciTech Connect (OSTI)

    Ottonello, Giulio; Richet, Pascal

    2014-01-28

    The existing solubility data on noble gases in high-temperature silicate melts have been analyzed in terms of Scaling Particle Theory coupled with an ab initio assessment of the electronic, dispersive, and repulsive energy terms based on the Polarized Continuum Model (PCM). After a preliminary analysis of the role of the contracted Gaussian basis sets and theory level in reproducing appropriate static dipole polarizabilities in a vacuum, we have shown that the procedure returns Henry's law constants consistent with the values experimentally observed in water and benzene at T = 25?°C and P = 1 bar for the first four elements of the series. The static dielectric constant (?) of the investigated silicate melts and its optical counterpart (?{sup ?}) were then resolved through the application of a modified form of the Clausius-Mossotti relation. Argon has been adopted as a probe to depict its high-T solubility in melts through an appropriate choice of the solvent diameter ?{sub s}, along the guidelines already used in the past for simple media such as water or benzene. The ?{sub s} obtained was consistent with a simple functional form based on the molecular volume of the solvent. The solubility calculations were then extended to He, Ne, and Kr, whose dispersive and repulsive coefficients are available from theory and we have shown that their ab initio Henry's constants at high T reproduce the observed increase with the static polarizability of the series element with reasonable accuracy. At room temperature (T = 25?°C) the calculated Henry's constants of He, Ne, Ar, and Kr in the various silicate media predict higher solubilities than simple extrapolations (i.e., Arrhenius plots) based on high-T experiments and give rise to smooth trends not appreciably affected by the static polarizabilities of the solutes. The present investigation opens new perspectives on a wider application of PCM theory which can be extended to materials of great industrial interest at the core of metallurgical processes, ceramurgy, and the glass industry.

  8. The role of DNA methylation in catechol-enhanced erythroid differentiation of K562 cells

    SciTech Connect (OSTI)

    Li, Xiao-Fei; Wu, Xiao-Rong; Xue, Ming; Wang, Yan; Wang, Jie; Li, Yang; Suriguga,; Zhang, Guang-Yao; Yi, Zong-Chun

    2012-11-15

    Catechol is one of phenolic metabolites of benzene in vivo. Catechol is also widely used in pharmaceutical and chemical industries. In addition, fruits, vegetables and cigarette smoke also contain catechol. Our precious study showed that several benzene metabolites (phenol, hydroquinone, and 1,2,4-benzenetriol) inhibited erythroid differentiation of K562 cells. In present study, the effect of catechol on erythroid differentiation of K562 cells was investigated. Moreover, to address the role of DNA methylation in catechol-induced effect on erythroid differentiation in K562 cells, methylation levels of erythroid-specific genes were analyzed by Quantitative MassARRAY methylation analysis platform. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation in K562 cells in concentration- and time-dependent manners. The mRNA expression of erythroid specific genes, including ?-globin, ?-globin, ?-globin, erythroid 5-aminolevulinate synthase, erythroid porphobilinogen deaminase, and transcription factor GATA-1 genes, showed a significant concentration-dependent increase in catechol-treated K562 cells. The exposure to catechol caused a decrease in DNA methylation levels at a few CpG sites in some erythroid specific genes including ?-globin, ?-globin and erythroid porphobilinogen deaminase genes. These results indicated that catechol improved erythroid differentiation potency of K562 cells at least partly via up-regulating transcription of some erythroid related genes, and suggested that inhibition of DNA methylation might be involved in up-regulated expression of some erythroid related genes. -- Highlights: ? Catechol enhanced hemin-induced hemoglobin accumulation. ? Exposure to catechol resulted in up-regulated expression of erythroid genes. ? Catechol reduced methylation levels at some CpG sites in erythroid genes.

  9. PROCESSING ALTERNATIVES FOR DESTRUCTION OF TETRAPHENYLBORATE

    SciTech Connect (OSTI)

    Lambert, D; Thomas Peters, T; Samuel Fink, S

    2007-02-27

    Two processes were chosen in the 1980's at the Savannah River Site (SRS) to decontaminate the soluble High Level Waste (HLW). The In Tank Precipitation (ITP) process (1,2) was developed at SRS for the removal of radioactive cesium and actinides from the soluble HLW. Sodium tetraphenylborate was added to the waste to precipitate cesium and monosodium titanate (MST) was added to adsorb actinides, primarily uranium and plutonium. Two products of this process were a low activity waste stream and a concentrated organic stream containing cesium tetraphenylborate and actinides adsorbed on monosodium titanate (MST). A copper catalyzed acid hydrolysis process was built to process (3, 4) the Tank 48H cesium tetraphenylborate waste in the SRS's Defense Waste Processing Facility (DWPF). Operation of the DWPF would have resulted in the production of benzene for incineration in SRS's Consolidated Incineration Facility. This process was abandoned together with the ITP process in 1998 due to high benzene in ITP caused by decomposition of excess sodium tetraphenylborate. Processing in ITP resulted in the production of approximately 1.0 million liters of HLW. SRS has chosen a solvent extraction process combined with adsorption of the actinides to decontaminate the soluble HLW stream (5). However, the waste in Tank 48H is incompatible with existing waste processing facilities. As a result, a processing facility is needed to disposition the HLW in Tank 48H. This paper will describe the process for searching for processing options by SRS task teams for the disposition of the waste in Tank 48H. In addition, attempts to develop a caustic hydrolysis process for in tank destruction of tetraphenylborate will be presented. Lastly, the development of both a caustic and acidic copper catalyzed peroxide oxidation process will be discussed.

  10. Catalytic hydrotreating of biomass liquefaction products to produce hydrocarbon fuels: Interim report

    SciTech Connect (OSTI)

    Elliott, D.C.; Baker, E.G.

    1986-03-01

    Research catalytic hydrotreatment of biomass liquefaction products to a gasoline has been technically demonstrated in a bench-scale continuous processing unit. This report describes the development of the chemistry needed for hydrotreatment of both high pressure and pyrolyzate biomass liquefaction products and outlines the important processing knowledge gained by the research. Catalyst identity is important in hydrotreatment of phenolics. Hydrogenation catalysts such as palladium, copper chromite, cobalt and nickel show activity with nickel being the most active. Major products include benzene, cyclohexane, and cyclohexanone. The hydrotreating catalysts cobalt-molybdenum, nickel-molybdenum and nickel-tungsten exhibit some activity when added to the reactor in the oxide form and show a great specificity for hydrodeoxygenation of phenol without saturation of the benzene product. The sulfide form of these catalysts is much more active than the oxide form and, in the case of the cobalt-molybdenum, much of the specificity for hydrodeoxygenation is retained. Substitution on the phenolic ring has only marginal effects on the hydrotreating reaction. However, the methoxy (OCH/sub 3/) substituent on the phenol ring is thermally unstable relative to other phenolics tested. The pyrolysis products dominate the product distribution when cobalt-molybdenum is used as the hydrotreating catalyst for methoxyphenol. The product from catalytic hydrotreatment of high-pressure biomass liquefaction products confirms the model compounds studies. Catalytic processing at 350 to 400/sup 0/C and 2000 psig with the sulfided cobalt-molybdenum or nickel-molybdenum catalyst produced a gasoline-like product composed of cyclic and aromatic compounds. Oxygen contents in products were in the range of 0 to 0.7 wt % and hydrogen to carbon atomic ratios ranged from 1.5 to 2.0. 46 refs., 10 figs., 21 tabs.

  11. Final Report: Investigation of Catalytic Pathways for Lignin Breakdown into Monomers and Fuels

    SciTech Connect (OSTI)

    Gluckstein, Jeffrey A; Hu, Michael Z.; Kidder, Michelle; McFarlane, Joanna; Narula, Chaitanya Kumar; Sturgeon, Matthew R

    2010-12-01

    Lignin is a biopolymer that comprises up to 35% of woody biomass by dry weight. It is currently underutilized compared to cellulose and hemicellulose, the other two primary components of woody biomass. Lignin has an irregular structure of methoxylated aromatic groups linked by a suite of ether and alkyl bonds which makes it difficult to degrade selectively. However, the aromatic components of lignin also make it promising as a base material for the production of aromatic fuel additives and cyclic chemical feed stocks such as styrene, benzene, and cyclohexanol. Our laboratory research focused on three methods to selectively cleave and deoxygenate purified lignin under mild conditions: acidolysis, hydrogenation and electrocatalysis. (1) Acidolysis was undertaken in CH2Cl2 at room temperature. (2) Hydrogenation was carried out by dissolving lignin and a rhodium catalyst in 1:1 water:methoxyethanol under a 1 atm H2 environment. (3) Electrocatalysis of lignin involved reacting electrically generated hydrogen atoms at a catalytic palladium cathode with lignin dissolved in a solution of aqueous methanol. In all of the experiments, the lignin degradation products were identified and quantified by gas chromatography mass spectroscopy and flame ionization detection. Yields were low, but this may have reflected the difficulty in recovering the various fractions after conversion. The homogeneous hydrogenation of lignin showed fragmentation into monomers, while the electrocatalytic hydrogenation showed production of polyaromatic hydrocarbons and substituted benzenes. In addition to the experiments, promising pathways for the conversion of lignin were assessed. Three conversion methods were compared based on their material and energy inputs and proposed improvements using better catalyst and process technology. A variety of areas were noted as needing further experimental and theoretical effort to increase the feasibility of lignin conversion to fuels.

  12. HCCI experiments with gasoline surrogate fuels modeled by a semidetailed chemical kinetic model

    SciTech Connect (OSTI)

    Andrae, J.C.G.; Head, R.A.

    2009-04-15

    Experiments in a homogeneous charge compression ignition (HCCI) engine have been conducted with four gasoline surrogate fuel blends. The pure components in the surrogate fuels consisted of n-heptane, isooctane, toluene, ethanol and diisobutylene and fuel sensitivities (RON-MON) in the fuel blends ranged from two to nine. The operating conditions for the engine were p{sub in}=0.1 and 0.2 MPa, T{sub in}=80 and 250 C, {phi}=0.25 in air and engine speed 1200 rpm. A semidetailed chemical kinetic model (142 species and 672 reactions) for gasoline surrogate fuels, validated against ignition data from experiments conducted in shock tubes for gasoline surrogate fuel blends at 1.0{<=} p{<=}5.0MPa, 700{<=} T{<=}1200 K and {phi}=1.0, was successfully used to qualitatively predict the HCCI experiments using a single zone modeling approach. The fuel blends that had higher fuel sensitivity were more resistant to autoignition for low intake temperature and high intake pressure and less resistant to autoignition for high intake temperature and low intake pressure. A sensitivity analysis shows that at high intake temperature the chemistry of the fuels ethanol, toluene and diisobutylene helps to advance ignition. This is consistent with the trend that fuels with the least Negative Temperature Coefficient (NTC) behavior show the highest octane sensitivity, and become less resistant to autoignition at high intake temperatures. For high intake pressure the sensitivity analysis shows that fuels in the fuel blend with no NTC behavior consume OH radicals and acts as a radical scavenger for the fuels with NTC behavior. This is consistent with the observed trend of an increase in RON and fuel sensitivity. With data from shock tube experiments in the literature and HCCI modeling in this work, a correlation between the reciprocal pressure exponent on the ignition delay to the fuel sensitivity and volume percentage of single-stage ignition fuel in the fuel blend was found. Higher fuel sensitivity and single-stage fuel content generally gives a lower value of the pressure exponent. This helps to explain the results obtained while boosting the intake pressure in the HCCI engine. (author)

  13. ANAEROBIC BIOLOGICAL TREATMENT OF PRODUCED WATER

    SciTech Connect (OSTI)

    John R. Gallagher

    2001-07-31

    During the production of oil and gas, large amounts of water are brought to the surface and must be disposed of in an environmentally sensitive manner. This is an especially difficult problem in offshore production facilities where space is a major constraint. The chief regulatory criterion for produced water is oil and grease. Most facilities have little trouble meeting this criterion using conventional oil-water separation technologies. However, some operations have significant amounts of naphthenic acids in the water that behave as oil and grease but are not well removed by conventional technologies. Aerobic biological treatment of naphthenic acids in simulated-produced water has been demonstrated by others; however, the system was easily overloaded by the large amounts of low-molecular-weight organic acids often found in produced waters. The objective of this research was to determine the ability of an anaerobic biological system to treat these organic acids in a simulated produced water and to examine the potential for biodegradation of the naphthenic acids in the anaerobic environment. A small fixed-film anaerobic biological reactor was constructed and adapted to treat a simulated produced water. The bioreactor was tubular, with a low-density porous glass packing material. The inocula to the reactor was sediment from a produced-water holding pond from a municipal anaerobic digester and two salt-loving methanogenic bacteria. During start-up, the feed to the reactor contained glucose as well as typical produced-water components. When glucose was used, rapid gas production was observed. However, when glucose was eliminated and the major organic component was acetate, little gas was generated. Methane production from acetate may have been inhibited by the high salt concentrations, by sulfide, or because of the lack, despite seeding, of microbes capable of converting acetate to methane. Toluene, a minor component of the produced water (0.1 g/L) was removed in the reactor. Batch tests were conducted to examine naphthenic acid biodegradability under several conditions. The conditions used were seed from the anaerobic reactor, wetland sediments under aerobic and anaerobic conditions, and a sterile control. The naphthenic acid was from a commercial source isolated from Gulf Coast petroleum as was dosed at 2 mg/mL. The incubations were for 30 days at 30 C. The results showed that the naphthenic acids were not biodegraded under anaerobic conditions, but were degraded under aerobic conditions. Despite poor performance of the anaerobic reactor, it remains likely that anaerobic treatment of acetate, toluene, and, potentially, other produced-water components is feasible.

  14. Demonstration of multifunctional DNBM corrosion inhibitors in protective coatings for Naval Air/Weapon Systems. Final report, September 1989-July 1992

    SciTech Connect (OSTI)

    Bailin, L.J.

    1993-12-01

    The corrosion protective properties of multifunctional DNBM salts (quaternary ammonium dichromate, nitrate, borate, and molybdate) have been demonstrated on high-strength steel and aluminum alloys found in prototype aerospace weapon systems. The 100% DNBM mixture added to MIL-P-23377 epoxy-polyamide, minus strontium chromate inhibitor, on bare 7075-T6 aluminum alloy resisted 1000 h ASTM B-117 salt spray. However, the coatings were not resistant to hydraulic fluid immersion at the higher concentrations required for the corrosion inhibition. Microencapsulation of the reactive DNBM mixture was adopted as a means to prevent this susceptibility, as well as the destructive oxidation of the hydroxyl groups in the epoxy resin during cure. In the scale-up operation, approximately 20 gallons of DNBM weighing 64 kg (141 lb) was prepared from the four starting quarternary salts synthesized in a chemical process pilot plant. The salts were mixed by dissolving in toluene. Following removal of solvent, the resultant dark-brown liquid, approximating molasses in viscosity, was microencapsulated by the following method: The DNBM was dispersed to form an oil-in-water emulsion in an aqueous colloidal solution of low-viscosity, high-purity methyl cellulose using a Gifford-Wood homogenizer, followed by spray drying in an Anhydro spray dryer. The maximum practicable payload was 75% DNBM. After spray drying, the capsules Corrosion inhibitors, DNBM, Microencapsulation, Epoxy primers, Protective coatings.

  15. Thermal stability, acidity, catalytic properties, and deactivation behaviour of SAPO-5 catalysts: Effect of silicon content, acid treatment, and Na exchange

    SciTech Connect (OSTI)

    Akolekar, D.B.

    1994-09-01

    Crystalline microporous SAPO-5 molecular sieves with different silicon content, acid-treated SAPO-5 and Na-exchanged SAPO-5 were investigated for their thermal stability, and acidic and catalytic properties. SAPO-5 materials with increasing SI framework content exhibited lower thermal stability. The effects of the thermal treatment and Na exchange on the N{sub 2}-sorption capacity (at 78 K) of these materials were studied. In situ IR spectroscopic investigations of pyridine chemisorbed on the aluminophosphate catalysts revealed that the concentration of Broensted and Lewis acid sites are strongly affected by the Si content in the AlPO{sub 4} framework, acid treatment, and Na exchange. The results of temperature programmed desorption (TPD) and stepwise thermal desorption of pyridine suggest that there exists a broad site energy distribution over the aluminophosphate catalysts increases with the increasing Si content in the AlPO{sub 4} framework. The acid treatment and Na exchange showed a decrease in the number of strong acid sites on SAPO-5. The TPD of pyridine over SAPO-5, acid-treated SAPO-5, and Na-exchanged SAPO-5 indicated the presence of two types of acid sites. Correlation between the number of strong acid sites (measured in terms of the chemisorption of pyridine at 673 K) and framework charge on the aluminophosphate catalysts has also been obtained. The catalytic activities of SAPO-5 catalysts in the ethanol, n-hexane, isooctane, toluene, and o-xylene conversion reactions were studied. 22 refs., 11 figs., 5 tabs.

  16. Carbon based thirty six atom spheres

    DOE Patents [OSTI]

    Piskoti, Charles R.; Zettl, Alex K.; Cohen, Marvin L.; Cote, Michel; Grossman, Jeffrey C.; Louie, Steven G.

    2005-09-06

    A solid phase or form of carbon is based on fullerenes with thirty six carbon atoms (C.sub.36). The C.sub.36 structure with D.sub.6h symmetry is one of the two most energetically favorable, and is conducive to forming a periodic system. The lowest energy crystal is a highly bonded network of hexagonal planes of C.sub.36 subunits with AB stacking. The C.sub.36 solid is not a purely van der Waals solid, but has covalent-like bonding, leading to a solid with enhanced structural rigidity. The solid C.sub.36 material is made by synthesizing and selecting out C.sub.36 fullerenes in relatively large quantities. A C.sub.36 rich fullerene soot is produced in a helium environment arc discharge chamber by operating at an optimum helium pressure (400 torr). The C.sub.36 is separated from the soot by a two step process. The soot is first treated with a first solvent, e.g. toluene, to remove the higher order fullerenes but leave the C.sub.36. The soot is then treated with a second solvent, e.g. pyridine, which is more polarizable than the first solvent used for the larger fullerenes. The second solvent extracts the C.sub.36 from the soot. Thin films and powders can then be produced from the extracted C.sub.36. Other materials are based on C.sub.36 fullerenes, providing for different properties.

  17. Conformation of ionizable poly Para phenylene ethynylene in dilute solutions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wijesinghe, Sidath; Maskey, Sabina; Perahia, Dvora; Grest, Gary S.

    2015-11-03

    The conformation of dinonyl poly para phenylene ethynylenes (PPEs) with carboxylate side chains, equilibrated in solvents of different quality is studied using molecular dynamics simulations. PPEs are of interest because of their tunable electro-optical properties, chemical diversity, and functionality which are essential in wide range of applications. The polymer conformation determines the conjugation length and their assembly mode and affects electro-optical properties which are critical in their current and potential uses. The current study investigates the effect of carboxylate fraction on PPEs side chains on the conformation of chains in the dilute limit, in solvents of different quality. The dinonylmore » PPE chains are modeled atomistically, where the solvents are modeled both implicitly and explicitly. Dinonyl PPEs maintained a stretched out conformation up to a carboxylate fraction f of 0.7 in all solvents studied. The nonyl side chains are extended and oriented away from the PPE backbone in toluene and in implicit good solvent whereas in water and implicit poor solvent, the nonyl side chains are collapsed towards the PPE backbone. Thus, rotation around the aromatic ring is fast and no long range correlations are seen within the backbone.« less

  18. Separation of Trivalent Actinides from Lanthanides Using a Capillary Electrophoresis

    SciTech Connect (OSTI)

    Mori, Tomotaka; Ishii, Yasuo; Hayashi, Kazunori; Suganuma, Hideo; Satoh, Isamu

    2007-07-01

    A separation of {sup 241}Am(III) from {sup 152,154}Eu(III) was carried out using a capillary electrophoresis technique in a mixed solvent (CH{sub 3}OH/H{sub 2}O) system containing thiocyanate ion. First, the formation constants ({beta}{sub n}) between thiocyanate ion and Eu(III) or Am(III) were investigated in the mixed solvent solutions by a back-extraction technique using bis (2-ethylhexyl) hydrogen phosphate-toluene. The mean charges calculated on the basis of the data of {beta}{sub n} for Eu(III) were comparatively higher than those for Am(III). Based on the differences between the mean charges of Eu(III) and Am(III), separations for Am(III)/Eu(III) by means of capillary electrophoresis technique were tried in the (H{sup +}, Na{sup +})(SCN{sup -}, ClO{sub 4}{sup -}) mixed solvent solutions. It was proved that Am(III) was completely separated from Eu(III). (authors)

  19. Comparison of advanced distillation control methods. Second annual report

    SciTech Connect (OSTI)

    1996-11-01

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to study the issue of configuration selection for diagonal PI dual composition controls. ATV identification with on-line detuning was used for tuning the diagonal PI composition controllers. Each configuration was evaluated with respect to steady-state RGA values, sensitivity to feed composition changes, and open loop dynamic performance. Each configuration was tuned using setpoint changes over a wider range of operation for robustness and tested for feed composition upsets. Overall, configuration selection was shown to have a dominant effect upon control performance. Configuration analysis tools (e.g., RGA, condition number, disturbance sensitivity), were found to reject configuration choices that are obviously poor choices, but were unable to critically differentiate between the remaining viable choices. Configuration selection guidelines are given although it is demonstrated that the most reliable configuration selection approach is based upon testing the viable configurations using dynamic column simulators.

  20. Comparison of advanced distillation control methods. Second annual report

    SciTech Connect (OSTI)

    Riggs, J.B.

    1996-11-01

    Detailed dynamic simulations of two industrial distillation columns (a propylene/propane splitter and a xylene/toluene column) have been used to study the issue of configuration selection for diagonal PI dual composition controls. Auto Tune Variation (ATV) identification with on-line detuning was used for tuning the diagonal proportional integral (PI) composition controls. Each configuration was evaluated with respect to steady-state relative gain array (RGA) values, sensitivity to feed composition changes, and open loop dynamic performance. Each configuration was tuned using setpoint changes over a wider range of operation for robustness and tested for feed composition upsets. Overall, configuration selection was shown to have a dominant effect upon control performance. Configuration analysis tools (e.g., RGA, condition number, disturbance sensitivity) were found to reject configuration choices that are obviously poor choices, but were unable to critically differentiate between the remaining viable choices. Configuration selection guidelines are given although it is demonstrated that the most reliable configuration selection approach is based upon testing the viable configurations using dynamic column simulators.

  1. Comparison of advanced distillation control methods. Fourth annual report

    SciTech Connect (OSTI)

    Riggs, J.B.

    1998-09-01

    Detailed dynamic simulations of three industrial columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selection for single-ended and dual-composition control as well as compare conventional and advanced control approaches. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that in order to identify the optimum configuration, detailed testing using dynamic simulation is required. The optimum configurations were used to evaluate the control performance of conventional PI controllers, DMC (Dynamic Matrix Control), PMBC (Process Model Based Control), and ANN (Artificial Neural Networks) control. It was determined that DMC works best when one product is much more important than the other while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and DMC.

  2. Aging of secondary organic aerosol from small aromatic VOCs. Changes in chemical composition, mass yield, volatility and hygroscopicity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hildebrandt Ruiz, L.; Paciga, A. L.; Cerully, K.; Nenes, A.; Donahue, N. M.; Pandis, S. N.

    2014-12-12

    Secondary organic aerosol (SOA) is transformed after its initial formation, but this chemical aging of SOA is poorly understood. Experiments were conducted in the Carnegie Mellon environmental chamber to form and transform SOA from the photo-oxidation of toluene and other small aromatic volatile organic compounds (VOCs) in the presence of NOx. The effects of chemical aging on organic aerosol (OA) composition, mass yield, volatility and hygroscopicity were explored. Higher exposure to the hydroxyl radical resulted in different OA composition, average carbon oxidation state OSC) and mass yield. The OA oxidation state generally increased during photo-oxidation, and the final OA OSmore » C ranged from -0.29 to 0.45 in the performed experiments. The volatility of OA formed in these different experiments varied by as much as a factor of 30, demonstrating that the OA formed under different oxidizing conditions can have significantly different saturation concentration. There was no clear correlation between hygroscopicity and oxidation state for this relatively hygroscopic SOA.« less

  3. Nanocrystal quantum dots: building blocks for tunable optical amplifiers and lasers

    SciTech Connect (OSTI)

    Mikhailovsky, A. A.; Malko, A. V.; Klimov, V. I.; Leatherdale, C. A.; Eisler, H-J.; Bawendi, M.; Hollingsworth, J. A.

    2001-01-01

    We study optical processes relevant to optical amplification and lasing in CdSe nanocrystal quantum dots (NQD). NQDs are freestanding nanoparticles prepared using solution-based organometallic reactions originally developed for the Cd chalcogenides, CdS, CdSe and CdTe [J. Am. Chem. Soc. 115, 8706 (1993)]. We investigate NQDs with diameters ranging from 2 to 8 nm. Due to strong quantum confinement, they exhibit size-dependent spectral tunability over an energy range as wide as several hundred meV. We observe a strong effect of the matrix/solvent on optical gain properties of CdSe NQDs. In most of the commonly used solvents (such as hexane and toluene), gain is suppressed due to strong photoinduced absorption associated with carriers trapped at solvent-related interface states. In contrast, matrix-free close packed NQD films (NQD solids) exhibit large optical gain with a magnitude that is sufficiently high for the optical gain to successfully compete with multiparticle Auger recombination [Science 287, 10117 (2000)]. These films exhibit narrowband stimulated emission at both cryogenic and room temperature, and the emission color is tunable with dot size [Science 290, 314 (2000)]. Moreover, the NQD films can be incorporated into microcavities of different geometries (micro-spheres, wires, tubes) that produce lasing in whispering gallery modes. The facile preparation, chemical flexibility and wide-range spectral tunability due to strong quantum confinement are the key advantages that should motivate research into NQD applications in optical amplifiers and lasers.

  4. Detailed Chemical Kinetic Modeling of Surrogate Fuels for Gasoline and Application to an HCCI Engine

    SciTech Connect (OSTI)

    Naik, C V; Pitz, W J; Sj?berg, M; Dec, J E; Orme, J; Curran, H J; Simmie, J M; Westbrook, C K

    2005-01-07

    Gasoline consists of many different classes of hydrocarbons, such as paraffins, olefins, aromatics, and cycloalkanes. In this study, a surrogate gasoline reaction mechanism is developed, and it has one representative fuel constituent from each of these classes. These selected constituents are iso-octane, n-heptane, 1-pentene, toluene, and methyl-cyclohexane. The mechanism was developed in a step-wise fashion, adding submechanisms to treat each fuel component. Reactions important for low temperature oxidation (<1000K) and cross-reactions among different fuels are incorporated into the mechanism. The mechanism consists of 1214 species and 5401 reactions. A single-zone engine model is used to evaluate how well the mechanism captures autoignition behavior for conditions corresponding to homogeneous charge compression ignition (HCCI) engine operation. Experimental data are available for both how the combustion phasing changes with fueling at a constant intake temperature, and also how the intake temperature has to be changed with pressure in order to maintain combustion phasing for a fixed equivalence ratio. Three different surrogate fuel mixtures are used for the modeling. Predictions are in reasonably good agreement with the engine data. In addition, the heat release rate is calculated and compared to the data from experiments. The model predicts less low-temperature heat release than that measured. It is found that the low temperature heat-release rate depends strongly on engine speed, reactions of RO{sub 2}+HO{sub 2}, fuel composition, and pressure boost.

  5. Method for depositing a uniform layer of particulate material on the surface of an article having interconnected porosity

    DOE Patents [OSTI]

    Wrenn, Jr., George E. (Clinton, TN); Lewis, Jr., John (Oak Ridge, TN)

    1984-01-01

    The invention is a method for depositing liquid-suspended particles on an immersed porous article characterized by interconnected porosity. In one form of the invention, coating is conducted in a vessel containing an organic liquid supporting a colloidal dispersion of graphite sized to lodge in surface pores of the article. The liquid comprises a first volatile component (e.g., acetone) and a second less-volatile component (e.g., toluene) containing a dissolved organic graphite-bonding agent. The liquid also contains an organic agent (e.g., cellulose gum) for maintaining the particles in suspension. A porous carbon article to be coated is immersed in the liquid so that it is permeated therewith. While the liquid is stirred to maintain a uniform blend, the vessel headspace is evacuated to effect flashing-off of the first component from the interior of the article. This causes particle-laden liquid exterior of the article to flow inwardly through its surface pores, lodging particles in these pores and forming a continuous graphite coating. The coated article is retrieved and heated to resin-bond the graphite. The method can be used to form a smooth, adherent, continuous coating of various materials on various porous articles. The method is rapid and reproducible.

  6. Particle Release Experiment (PRex) Final Report

    SciTech Connect (OSTI)

    Keillor, Martin E.; Arrigo, Leah M.; Detwiler, Rebecca S.; Kernan, Warnick J.; Kirkham, Randy R.; MacDougall, Matthew R.; Chipman, Veraun D.; Milbrath, Brian D.; Rishel, Jeremy P.; Seifert, Allen; Seifert, Carolyn E.; Smart, John E.; Emer, Dudley

    2014-09-30

    An experiment to release radioactive particles representative of small-scale venting from an underground nuclear test was conducted to gather data in support of treaty verification and monitoring activities. For this experiment, a CO2-driven “air cannon” was used to release La-140 at ambient temperatures. Lanthanum-140 was chosen to represent the fission fragments because of its short half-life and prominent gamma-ray emissions; the choice was also influenced by the successful production and use of La-140 with low levels of radioactive contaminants in a Defence Research and Development Canada Field Trial. The source was created through activation of high-purity natural lanthanum oxide at the reactor of Washington State University, Pullman, Washington. Multiple varieties of witness plates and air samplers were laid in an irregular grid covering the area over which the plume was modeled to deposit. Aerial survey, a NaI(Tl) mobile spectrometer, and handheld and backpack instruments ranging from polyvinyl toluene to high-purity germanium were used to survey the plume. Additionally, three varieties of soil sampling were investigated. The relative sensitivity and utility of sampling and survey methods are discussed in the context of On-Site Inspection. The measurements and samples show a high degree of correlation and form a valuable set of test data.

  7. Macromolecular coal structure as revealed by novel diffusion tests

    SciTech Connect (OSTI)

    Peppas, N.A.; Olivares, J.; Drummond, R.; Lustig, S.

    1990-01-01

    The main goal of the present work was the elucidation of the mechanistic characteristics of dynamic transport of various penetrants (solvents) in thin sections of coals by examining their penetrant uptake, front swelling and stress development. An important objective of this work was the study of coal network structure in different thermodynamically compatible penetrants and the analysis of dynamic swelling in terms of present anomalous transport theories. Interferometry/polariscopy, surface image analysis and related techniques were used to quantify the stresses and solvent concentration profiles in these sections. Dynamic and equilibrium swelling behavior were correlated using the polar interaction contributions of the solvent solubility parameters. The penetrant front position was followed in thin coal sections as a function of time. The initial front velocity was calculated for various coals and penetrants. Our penetrant studies with thin coal section from the same coal sample but with different thickness show that within the range of 150 {mu}m to 1500{mu}m the transport mechanism of dimethyl formamide in the macromolecular coal network is non-Fickian. In fact, for the thickest samples the transport mechanism is predominately Case-II whereas in the thinner samples penetrant uptake may be diffusion-controlled. Studies in various penetrants such as acetone, cyclohexane, methanol, methyl ethyl ketone, toluene and methylene chloride indicated that penetrant transport is a non-Fickian phenomenon. Stresses and cracks were observed for transport of methylene chloride. 73 refs., 88 figs., 15 tabs.

  8. Method for depositing a uniform layer of particulate material on the surface of an article having interconnected porosity

    DOE Patents [OSTI]

    Wrenn, G.E. Jr.; Lewis, J. Jr.

    1982-09-29

    The invention is a method for depositing liquid-suspended particles on an immersed porous article characterized by interconnected porosity. In one form of the invention, coating is conducted in a vessel containing an organic liquid supporting a colloidal dispersion of graphite sized to lodge in surface pores of the article. The liquid comprises a first volatile component (e.g., acetone) and a second less-volatile component (e.g., toluene) containing a dissolved organic graphite-bonding agent. The liquid also contains an organic agent (e.g., cellulose gum) for maintaining the particles in suspension. A porous carbon article to be coated is immersed in the liquid so that it is permeated therewith. While the liquid is stirred to maintain a uniform blend, the vessel headspace is evacuated to effect flashing-off of the first component from the interior of the article. This causes particle-laden liquid exterior of the article to flow inwardly through its surface pores, lodging particles in these pores and forming a continuous graphite coating. The coated article is retrieved and heated to resin-bond the graphite. The method can be used to form a smooth, adherent, continuous coating of various materials on various porous articles. The method is rapid and reproducible.

  9. Photoinduced Surface Oxidation and Its Effect on the Exciton Dynamics of CdSe Quantum Dots

    SciTech Connect (OSTI)

    Hines, Douglas A.; Becker, Matthew A.; Kamat, Prashant V.

    2012-11-14

    With increased interest in semiconductor nanoparticles for use in quantum dot solar cells there comes a need to understand the long-term photostability of such materials. Colloidal CdSe quantum dots (QDs) were suspended in toluene and stored in combinations of light/dark and N{sub 2}/O{sub 2} to simulate four possible benchtop storage environments. CdSe QDs stored in a dark, oxygen-free environment were observed to better retain their optical properties over the course of 90 days. The excited state lifetimes, determined through femtosecond transient absorption spectroscopy, of air-equilibrated samples exposed to light exhibit a decrease in average lifetime (0.81 ns) when compared to samples stored in a nitrogen/dark environment (8.3 ns). A photoetching technique commonly used for controlled reduction of QD size was found to induce energetic trap states to CdSe QDs and accelerate the rate of electron-hole recombination. X-ray absorption near edge structure (XANES) analysis confirms surface oxidation, the extent of which is shown to be dependent on the thickness of the ligand shell.

  10. Structure of rigid polymers confined to nanoparticles: Molecular dynamics simulations insight

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Maskey, Sabina; Lane, J. Matthew D.; Perahia, Dvora; Grest, Gary S.

    2016-02-04

    Nanoparticles (NPs) grafted with organic layers form hybrids able to retain their unique properties through integration into the mesoscopic scale. The organic layer structure and response often determine the functionality of the hybrids on the mesoscopic length scale. Using molecular dynamics (MD) simulations, we probe the conformation of luminescent rigid polymers, dialkyl poly(p-phenylene ethynylene)s (PPE), end-grafted onto a silica nanoparticle in different solvents as the molecular weights and polymer coverages are varied. We find that, in contrast to NP-grafted flexible polymers, the chains are fully extended independent of the solvent. In toluene and decane, which are good solvents, the graftedmore » PPEs chains assume a similar conformation to that observed in dilute solutions. In water, which is a poor solvent for the PPEs, the polymer chains form one large cluster but remain extended. The radial distribution of the chains around the core of the nanoparticle is homogeneous in good solvents, whereas in poor solvents clusters are formed independent of molecular weights and coverages. As a result, the clustering is distinctively different from the response of grafted flexible and semiflexible polymers.« less

  11. A combustion model for IC engine combustion simulations with multi-component fuels

    SciTech Connect (OSTI)

    Ra, Youngchul; Reitz, Rolf D.

    2011-01-15

    Reduced chemical kinetic mechanisms for the oxidation of representative surrogate components of a typical multi-component automotive fuel have been developed and applied to model internal combustion engines. Starting from an existing reduced mechanism for primary reference fuel (PRF) oxidation, further improvement was made by including additional reactions and by optimizing reaction rate constants of selected reactions. Using a similar approach to that used to develop the reduced PRF mechanism, reduced mechanisms for the oxidation of n-tetradecane, toluene, cyclohexane, dimethyl ether (DME), ethanol, and methyl butanoate (MB) were built and combined with the PRF mechanism to form a multi-surrogate fuel chemistry (MultiChem) mechanism. The final version of the MultiChem mechanism consists of 113 species and 487 reactions. Validation of the present MultiChem mechanism was performed with ignition delay time measurements from shock tube tests and predictions by comprehensive mechanisms available in the literature. A combustion model was developed to simulate engine combustion with multi-component fuels using the present MultiChem mechanism, and the model was applied to simulate HCCI and DI engine combustion. The results show that the present multi-component combustion model gives reliable performance for combustion predictions, as well as computational efficiency improvements through the use of reduced mechanism for multi-dimensional CFD simulations. (author)

  12. Methane ignition catalyzed by in situ generated palladium nanoparticles

    SciTech Connect (OSTI)

    Shimizu, T.; Abid, A.D.; Poskrebyshev, G.; Wang, H. [Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90089 (United States); Nabity, J.; Engel, J.; Yu, J. [TDA Research, Inc., 12345 W. 52nd Ave, Wheat Ridge, CO 80033 (United States); Wickham, D. [Reaction Systems, LLC, 19039 E. Plaza Drive, Suite 290, Parker, CO 80134 (United States); Van Devener, B.; Anderson, S.L. [Department of Chemistry, University of Utah, Salt Lake City, UT 84112 (United States); Williams, S. [Air Force Research Laboratory, Mail Stop RZA, 1950 Fifth Street, WPAFB, OH 45433 (United States)

    2010-03-15

    Catalytic ignition of methane over the surfaces of freely-suspended and in situ generated palladium nanoparticles was investigated experimentally and numerically. The experiments were conducted in a laminar flow reactor. The palladium precursor was a compound (Pd(THD){sub 2}, THD: 2,2,6,6-tetramethyl-3,5-heptanedione) dissolved in toluene and injected into the flow reactor as a fine aerosol, along with a methane-oxygen-nitrogen mixture. For experimental conditions chosen in this study, non-catalytic, homogeneous ignition was observed at a furnace temperature of {proportional_to}1123 K, whereas ignition of the same mixture with the precursor was found to be {proportional_to}973 K. In situ production of Pd/PdO nanoparticles was confirmed by scanning mobility, transmission electron microscopy and X-ray photoelectron spectroscopy analyses of particles collected at the reactor exit. The catalyst particle size distribution was log-normal. Depending on the precursor loading, the median diameter ranged from 10 to 30 nm. The mechanism behind catalytic ignition was examined using a combined gas-phase and gas-surface reaction model. Simulation results match the experiments closely and suggest that palladium nanocatalyst significantly shortens the ignition delay times of methane-air mixtures over a wide range of conditions. (author)

  13. Superfund Record of Decision (Region 2): Love Canal/93rd Street, New York (third remedial action), September 1988

    SciTech Connect (OSTI)

    Not Available

    1988-09-26

    The Love Canal/93rd Street School site consists of approximately 19 acres and includes a school and an adjacent vacant lot. The site is located in Niagara Falls, New York, less than one mile northwest of Love Canal and is within the Love Canal Emergency Declaration Area. Hooker Chemicals and Plastics Corporation disposed of over 21,000 tons of various chemicals at the Love Canal site from 1942 to 1953, when the site was deeded over to the City of Niagara Falls Board of Education. Sampling has revealed that approximately 6,000 cu yds of soil are contaminated. During the 1950s, home construction accelerated in the area. Specifically, in 1950, the 93rd Street School was built, and in 1954, the 99th Street School was built adjacent to the middle portion of the Canal. Prior to construction of the 93rd Street School, a drainage swale crossed the site. Between 1938 and 1951, the swale was partially filled with soil and rock debris, followed by sand and fly ash materials. In 1980, the 93rd Street School was closed due to public health concerns related to the potentially contaminated fill material. The primary contaminants of concern affecting soil are VOCs, including toluene and xylenes, other organics including dioxins, PAHs and pesticides, and metals including arsenic and lead.

  14. Experimental and Theoretical Study of Molecular Response of Amine Bases in Organic Solvents

    SciTech Connect (OSTI)

    Kathmann, Shawn M.; Cho, Herman M.; Chang, Tsun-Mei; Schenter, Gregory K.; Parab, Kshitij K.; Autrey, Thomas

    2014-05-08

    Reorientational correlation times of various amine bases (viz., pyridine, 2,6-lutidene, 2,2,6,6-tetramethylpiperidine) and organic solvents (dichloromethane, toluene) were determined by solution-state NMR relaxation time measurements and compared with predictions from molecular dynamics (MD) simulations. The bases and solvents are reagents in complex reactions involving Frustrated Lewis Pairs (FLP), which display remarkable catalytic activity in metal-free H2 scission. The comparison of measured and simulated correlation times is a key test of the ability of recent MD and quantum electronic structure calculations to elucidate the mechanism of FLP activity. Correla- tion times were found to be in the range 1.4-3.4 ps (NMR) and 1.23-5.28 ps (MD) for the amines, and 0.9-2.3 ps (NMR) and 0.2-1.7 ps (MD) for the solvent molecules. This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacic Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle.

  15. Volatile organic chemical emissions from carpet cushions: Screening measurements. Final report

    SciTech Connect (OSTI)

    Hodgson, A.T.; Phan, T.A.

    1994-05-01

    The US Consumer Product Safety Commission (CPSC) has received complaints from consumers regarding the occurrence of adverse health effects following the installation of new carpeting (Schachter, 1990). Carpet systems are suspected of emitting chemicals which may be the cause of these complaints, as well as objectionable odors. Carpets themselves have been shown to emit a variety of volatile organic compounds (VOCs). The objective of this study was to screen the representative samples of carpet cushions for emissions of individual VOCS, total VOCs (TVOC), formaldehyde, and, for the two types of polyurethane cushions, isomers of toluene diisocyanate (TDI). The measurements of VOCS, TVOC and formaldehyde were made over six-hour periods using small-volume (4-L) dynamic chambers. Sensitive gas chromatography-mass spectrometry (GC-MS) techniques were used to identify many of the VOCs emitted by the cushion samples and to obtain quantitative estimates of the emission rates of selected compounds. Separate screening measurements were conducted for TDI. The data from the screening measurements were used by the CPSC`s Health Sciences Laboratory to help design and conduct week-long measurements of emission rates of selected compounds.

  16. Health-hazard evaluation report HETA 90-223-2211, Thomson Consumer Electronics, Marion, Indiana

    SciTech Connect (OSTI)

    Lenhart, S.W.; Driscoll, R.

    1992-05-01

    In response to a request from the Corporate Medical Consultant to Thomson Consumer Electronics (SIC-3673), Marion, Indiana, a study was undertaken of an illness outbreak in workers at the facility. There were about 1900 workers at the facility, which produced television picture tubes. Production occurred over three shifts, 6 days a week. Charcoal tube sampling indicated the presence of acetone (67641) n-amyl-acetate (628637), n-butyl-acetate (123864), isoamyl-acetate (123922), toluene (108883), 1,1,1-trichloroethane (71556), and trichloroethylene (79016). No contaminants were detected in the bag samples of air collected from the in/house compressed air system. One or more symptoms were reported by 593 (82%) of the workers. Those most commonly reported included headache (68%), sore throat (53%), fatigue (51%), eye irritation (50%), itchy skin (47%), irritated nose (45%), dizziness (45%), unusual taste in mouth (45%), unusual smell (41%) and cough. The authors conclude that symptoms were consistent with stress related health complaints in occupational settings. Concentrations of chemicals measured in the facility would not be expected to produce the effects seen in the outbreak. The authors recommend that trichloroethylene degreasing units be replaced with equipment which uses a less toxic degreasing agent. The facility should hire a full time industrial hygienist.

  17. Advanced coal liquefaction. Final project report

    SciTech Connect (OSTI)

    1996-12-02

    Molecular level liquid phase separation was explored using modified microporous ceramic membranes with pore size reduced from 40{Angstrom} via chemical vapor deposition. At room temperature, membranes with pore sizes <30{Angstrom} were sufficient to achieve >97% rejection of naphthyl-bibenzyl-methane (NBBM) in toluene, likely attributed to the hindrance effect of NBBM through the porous avenue of the membrane. The rejection diminished dramatically as the temperature was increased. The permeance of the mixture was substantially lower than that of the solvent resulted from the interference by the solute through the transport avenue. Also, it was found that the rejection increases along with the transmembrane pressure increase, probably attributed to the pore size distribution of the membrane. The smaller pore sizes become accessible to the solvent while rejecting the solute at the higher pressure. In addition to size-based separation, active transport of molecules through an appropriate pore size at 300-400{degrees}C was observed, as a result of interaction with the surface. Decomposition of NBBM took place at 400{degrees}C in a modified membrane packed with the catalyst synthesized using the similar protocol as membranes. The separation property of this membrane at 400{degrees}C was analyzed indirectly based upon the reaction product distribution.

  18. Process for the removal of impurities from combustion fullerenes

    DOE Patents [OSTI]

    Alford, J. Michael; Bolskar, Robert

    2005-08-02

    The invention generally relates to purification of carbon nanomaterials, particularly fullerenes, by removal of PAHs and other hydrocarbon impurities. The inventive process involves extracting a sample containing carbon nanomaterials with a solvent in which the PAHs are substantially soluble but in which the carbon nanomaterials are not substantially soluble. The sample can be repeatedly or continuously extracted with one or more solvents to remove a greater amount of impurities. Preferred solvents include ethanol, diethyl ether, and acetone. The invention also provides a process for efficiently separating solvent extractable fullerenes from samples containing fullerenes and PAHs wherein the sample is extracted with a solvent in which both fullerenes and PAHs are substantially soluble and the sample extract then undergoes selective extraction to remove PAHs. Suitable solvents in which both fullerenes and PAHs are soluble include o-xylene, toluene, and o-dichlorobenzene. The purification process is capable of treating quantities of combustion soot in excess of one kilogram and can produce fullerenes or fullerenic soot of suitable purity for many applications.

  19. Formation of Pd/Au Nanostructures from Pd Nanowires via Galvanic Replacement Reaction

    SciTech Connect (OSTI)

    Teng,X.; Wang, Q.; Liu, P.; Han, W.; Frenkel, A.; Wen, W.; Marinkovic, N.; Hanson, J.; Rodriguez, J.

    2008-01-01

    Bimetallic nanostructures with non-random metal atoms distribution are very important for various applications. To synthesize such structures via benign wet chemistry approach remains challenging. This paper reports a synthesis of a Au/Pd alloy nanostructure through the galvanic replacement reaction between Pd ultrathin nanowires (2.4 {+-} 0.2 nm in width, over 30 nm in length) and AuCl3 in toluene. Both morphological and structural changes were monitored during the reaction up to 10 h. Continuous changes of chemical composition and crystalline structure from Pd nanowires to Pd68Au32 and Pd45Au55 alloys, and to Au nanoparticles were observed. More interestingly, by using combined techniques such as high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS), UV-vis absorption, and extended X-ray absorption fine structure (EXAFS) spectroscopy, we found the formation of Pd68Au32 non-random alloy with Au-rich core and Pd-rich shell, and random Pd45Au55 alloy with uniformly mixed Pd and Au atom inside the nanoparticles, respectively. Density functional theory (DFT) calculations indicated that alkylamine will strongly stabilize Pd to the surface, resulting in diffusion of Au atoms into the core region to form a non-random alloy. We believe such benign synthetic techniques can also enable the large scale preparation of various types of non-random alloys for several technically important catalysis applications.

  20. PVT-NG sensor final report.

    SciTech Connect (OSTI)

    Mitchell, Dean James; Brusseau, Charles A.

    2012-01-01

    This document is a final report for the polyvinyl toluene (PVT) neutron-gamma (PVT-NG) project, which was sponsored by the Domestic Nuclear Detection Office (DNDO). The PVT-NG sensor uses PVT detectors for both gamma and neutron detection. The sensor exhibits excellent spectral resolution and gain stabilization, which are features that are beneficial for detection of both gamma-ray and neutron sources. In fact, the ability to perform isotope identification based on spectra that were measured by the PVT-NG sensor was demonstrated. As described in a previous report, the neutron sensitivity of the first version of the prototype was about 25% less than the DNDO requirement of 2.5 cps/ng for bare Cf-252. This document describes design modifications that were expected to improve the neutron sensitivity by about 50% relative to the PVT-NG prototype. However, the project was terminated before execution of the design modifications after portal vendors demonstrated other technologies that enable neutron detection without the use of He-3. Nevertheless, the PVT-NG sensor development demonstrated several performance goals that may be useful in future portal designs.

  1. Pollution prevention assessment for a manufacturer of food service equipment

    SciTech Connect (OSTI)

    Edwards, H.W.; Kostrzewa, M.F.; Looby, G.P.

    1995-09-01

    The US Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. In an effort to assist these manufacturers Waste Minimization Assessment Centers (WMACs) were established at selected universities and procedures were adapted from the EPA Waste Minimization Opportunity Assessment Manual. The WMAC team at Colorado State University performed an assessment at a plant that manufacturers commercial food service equipment. Raw materials used by the plant include stainless steel, mild steel, aluminum, and copper and brass. Operations performing in the plant include cutting, forming, bending, welding, polishing, painting, and assembly The team`s report, detailing findings and recommendations, indicated that paint-related wastes (organic solvents) are generated in large quantities and that significant cost savings could be achieved by retrofitting the water curtain paint spray booth to operate as a dry filter paint booth. Toluene could be replaced by a less toxic solvent. This Research Brief was developed by the principal investigators and EPA`s National Risk Management Research Laboratory, Cincinnati, OH, to announce key findings of an ongoing research project that is fully documented in a separate report of the same title available from University City Science Center.

  2. Paso del Norte ozone study VOC measurements, 1996

    SciTech Connect (OSTI)

    Seila, R.L.; Main, H.; Arriaga, J.L.; Martinez, G.V.; Ramadan, A.B.

    1999-11-01

    The results of VOC determinations of ambient air samples collected at surface air quality monitoring sites and near sources of interest on the US and Mexican side of the border during six weeks of the 1996 Paso del Norte Ozone Study are reported. Carbonyl samples were collected on DNPH impregnated cartridges at three surface sites and analyzed by HPLC to quantify 13, C-1 to C-8 species. Whole air samples were collected in electro-polished stainless steel canisters which were returned to laboratory for determination of C-2 to C-10+ hydrocarbons by cryogenic preconcentration capillary gas chromatography with flame ionization detection (gc-fid). Several sources were sampled: rush hour traffic, propane-powered bus exhaust, automobile paint shop emissions, propane fuel, petroleum refinery, and industrial manufacturing site. Spatial and temporal characteristics of VOC species concentrations and compositions are presented. Overall surface TNMOC values ranged from 0.1 to 3.4 ppmC with the highest concentrations recorded in the morning at three vehicle-dominated sites, two in Cuidad Juarez and one in downtown El Paso. Toluene in El Paso samples and propane, which is used as a cooking and transportation fuel in Cuidad Juarez, were the most abundant hydrocarbons.

  3. Paso del Norte ozone study VOC measurements, 1996

    SciTech Connect (OSTI)

    Seila, R.L.; Main, H.; Arriaga, J.L.; Martinez, G.V.; Ramadan, A.B.

    1999-01-01

    The results of VOC determinations of ambient air samples collected at surface air quality monitoring sites and near sources of interest on the US and Mexican side of the border during six weeks of the 1996 Paso del Norte Ozone Study are reported. Carbonyl samples were collected on DNPH impregnated cartridges at three surface sites and analyzed by HPLC to quantify 13, C-1 to C-8 species. Whole air samples were collected in electro-polished stainless steel canisters which were returned to laboratory for determination of C-2 to C-10+ hydrocarbons by cryogenic preconcentration capillary gas chromatography with flame ionization detection (gc-fid). Several sources were sampled: rush hour traffic, propane-powered bus exhaust, automobile paint shop emissions, propane fuel, petroleum refinery, and industrial manufacturing site. Spatial and temporal characteristics of VOC species concentrations and compositions are presented. Overall surface TNMOC values ranged from 0.1 to 3.4 ppmC with the highest concentrations recorded in the morning at three vehicle-dominated sites, two in Cuidad Juarez and one in downtown El Paso. Toluene in El Paso samples and propane, which is used as a cooking and transportation fuel in Cuidad Juarez, were the most abundant hydrocarbons.

  4. Gas chromatographic determination of residual solvents in lubricating oils and waxes

    SciTech Connect (OSTI)

    De Andrade Bruening, I.M.R.

    1983-10-01

    A direct gas-liquid chromatographic analysis of residual solvents is described, using tert-butylbenzene as an internal standard. The lube oils and waxes were prevented from contaminating the chromatographic column by injecting the samples directly into a precolumn containing a silicone stationary phase. The samples of lube oils and waxes were injected directly into the chromatographic column containing another stationary phase, 1,2,3-tris(2-cyanoethoxy)propane. (The waxy samples were dissolved in a light neutral oil). With proper operating conditions, analysis time was 7 min. The procedure has been applied in the control of a lube oil dewaxing plant; the chromatographic column showed no sign of deterioration after 1 h when the precolumn was removed. Known amounts of toluene and methylethyl ketone were added to the solvent-free lubricating oils and wax, and these mixtures were analyzed to evaluate the accuracy of the procedure. Precision and accuracy of these data are comparable to those of methods previously described. 1 figure, 1 table.

  5. Comparison of two tunnel studies for non methane hydrocarbons in Mexico City

    SciTech Connect (OSTI)

    Mugica A, V.; Vega R, E.; Ruiz S, M.E.; Seila, R.

    1998-12-31

    Emissions from vehicles have long been considered a major source of pollutants involved in smog formation and ozone production. During the last few years, different control strategies have been taking place to reduce the high levels of ozone and some other atmospheric pollutants. Some of these strategies are: improvement of fuels, a program for compulsory vehicular emission test and the introduction of catalytic converters to be used in conjunction with unleaded gasoline since 1991. The comparison of the vehicular NMHC emission source profiles measured in a tunnel in Mexico City during March 1992 and May 1996 is presented. Samples were collected using stainless steel SUMMA{reg_sign} canisters and subsequent analyzed by gas chromatography with flame ionized detector. It was found that in general, the source profiles are similar, however, some differences were detected for some species. The sum of acetylene, ethylene and ethane contents, which are a typical combustion products, is lower for the 1996 source profile than for the 1992. In the same way, there is a small decrease of paraffin and olefin contents, except for hexane. Finally, significant differences were found for aromatic compounds, mainly toluene and xylenes which increased in 1996.

  6. Conformation of ionizable poly Para phenylene ethynylene in dilute solutions

    SciTech Connect (OSTI)

    Wijesinghe, Sidath; Maskey, Sabina; Perahia, Dvora; Grest, Gary S.

    2015-11-03

    The conformation of dinonyl poly para phenylene ethynylenes (PPEs) with carboxylate side chains, equilibrated in solvents of different quality is studied using molecular dynamics simulations. PPEs are of interest because of their tunable electro-optical properties, chemical diversity, and functionality which are essential in wide range of applications. The polymer conformation determines the conjugation length and their assembly mode and affects electro-optical properties which are critical in their current and potential uses. The current study investigates the effect of carboxylate fraction on PPEs side chains on the conformation of chains in the dilute limit, in solvents of different quality. The dinonyl PPE chains are modeled atomistically, where the solvents are modeled both implicitly and explicitly. Dinonyl PPEs maintained a stretched out conformation up to a carboxylate fraction f of 0.7 in all solvents studied. The nonyl side chains are extended and oriented away from the PPE backbone in toluene and in implicit good solvent whereas in water and implicit poor solvent, the nonyl side chains are collapsed towards the PPE backbone. Thus, rotation around the aromatic ring is fast and no long range correlations are seen within the backbone.

  7. Interfacial Modification of Silica Surfaces Through gamma-Isocyanatopropyl Triethoxy Silane-Amine Coupling Reactions

    SciTech Connect (OSTI)

    Vogel,B.; DeLongchamp, D.; Mahoney, C.; Lucas, L.; Fischer, D.; Lin, E.

    2008-01-01

    The development of robust, cost-effective methods to modify surfaces and interfaces without the specialized synthesis of unique coupling agents could provide readily accessible routes to optimize and tailor interfacial properties. We demonstrate that -isocyanatopropyl triethoxysilane (ISO) provides a convenient route to functionalize silica surfaces through coupling reactions with readily available reagents. ISO coupling agents layers (CALs) can be prepared from toluene with triethylamine (TEA), but the coupling reaction of an amine to the ISO CAL does not proceed. We use near edge X-ray absorption fine structure (NEXAFS), time-of-flight secondary ion mass spectrometry (TOF-SIMS) and sessile drop contact angle to demonstrate the isocyanate layer is not degraded under coupling conditions. Access to silanes with chemical functionality is possible with ISO by performing the coupling reaction in solution and then depositing the product onto the surface. Two model CAL surfaces are prepared to demonstrate the ease and robust nature of this procedure. The surfaces prepared using this method are the ISO reacted with octadecylamine to produce a hydrocarbon surface of similar quality to octadecyl trichlorosilane (OTS) CALs and with 9-aminofluorene (AFL), an aromatic amine functionality whose silane is otherwise unavailable commercially.

  8. Evaluation of innovative volatile organic compound and hazardous air-pollutant-control technologies for U. S. Air Force paint spray booths. Final report, Aug 88-Aug 89

    SciTech Connect (OSTI)

    Ritts, D.H.; Garretson, C.; Hyde, C.; Lorelli, J.; Wolbach, C.D.

    1990-10-01

    Significant quantities of volatile organic compounds (VOCs) and hazardous air pollutants are released into the atmosphere during USAF maintenance operations. Painting operations conducted in paint spray booths are major sources of these pollutants. Solvent based epoxy primers and solvent-based polyurethane coatings are typically used by the Air Force for painting aircraft and associated equipment. Solvents used in these paints include methyl ethyl ketone (MEK), toluene, lacquer thinner, and other solvents involved in painting and component cleaning. In this report, carbon paper adsorption/catalytic incineration (CPACI) and fluidized-bed catalytic incineration (FBCI) were evaluated as control technologies to destroy VOC emissions from paint spray booths. Simultaneous testing of pilot-scale units was performed to evaluate the technical performance of both technologies. Results showed that each technology maintained greater than 99 percent Destruction and Removal Efficiencies (DREs). Particulate emissions from both pilot-scale units were less than 0.08 grains/dry standard cubic foot. Emissions of the criteria pollutants--sulfur oxides, nitrogen oxides, and carbon monoxide--were also below general regulatory standards for incinerators. Economic evaluations were based on a compilation of manufacturer-supplied data and energy consuption data gathered during the pilot scale testing. CPACM and FBCI technologies are less expensive than standard VOC control technologies when net present costs for a 15-year equipment life are compared.

  9. Superfund Record of Decision (EPA Region 5): Naval Industrial Reserve Ordnance Plant, Fridley, MN. (First remedial action), September 1990

    SciTech Connect (OSTI)

    Not Available

    1990-09-28

    The 82.6-acre Naval Industrial Reserve Ordnance Plant (NIROP) site is a weapons system manufacturing facility in Fridley, Minnesota, which began operations in 1940. The site is a government-owned, contractor-operated, plant located just north of the FMC Corp. During the 1970s, paint sludge and chlorinated solvents were disposed of onsite in pits and trenches. In 1981, State investigations identified TCE in onsite water supply wells drawing from the Prairie DuChien/Jordan aquifer, and the wells were shut down. In 1983, EPA found drummed waste in the trenches or pits at the northern portion of the site, and as a result, during 1983 and 1984, the Navy authorized an installation restoration program, during which approximately 1,200 cubic yards of contaminated soil and 42 drums were excavated and landfilled offsite. The Record of Decision (ROD) addresses the remediation of a shallow ground water operable unit. The primary contaminants of concern affecting the ground water are VOCs including PCE, TCE, toluene, and xylene.

  10. Bioremediation of contaminated groundwater: A turnkey approach

    SciTech Connect (OSTI)

    Shivjiani, D.M.; Rudy, R.J.; Burns, B.; Heuler, G.

    1994-12-31

    The Silvex Corporation Site is a Florida state funded remedial action site in St. Augustine, Florida, that, prior to 1980, was a silver smelting facility that accepted waste materials from the Naval Air Station-Jacksonville. Fuels, reportedly consisting of waste paint, cold carbon removers, and solvent degreasers that were stored in a 25,000-gallon tank, spilled onto the property. The assessment concluded that the surficial aquifer in the spill area and the area hydrologically down-gradient of the spill were contaminated by elevated levels of ketones (acetone, methyl-ethyl ketone, and methyl-isobutyl ketone), phenols, and toluene. Subsequently, a risk assessment/feasibility study and groundwater bench-scale and pilot-scale studies were performed to determine the technical feasibility/cost-effectiveness of the recommended alternative, submerged fixed-film bioremediation. The on-site pilot study, which was conducted at three flow rates (0.5, 1, and 2 gallons per minute [gpm]), demonstrated a greater than 99% contaminant removal efficiency from the three-stage bioreactor. Due to the impact of site contamination on a nearby creek that flows into the St. Johns River, an interim remedial deign was developed and implemented to reduce the potential for migration of contaminated groundwater into the creek.

  11. Long-lived charge carrier generation in ordered films of a covalent perylenediimide–diketopyrrolopyrrole–perylenediimide molecule

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hartnett, Patrick E.; Dyar, Scott M.; Margulies, Eric A.; Shoer, Leah E.; Cook, Andrew W.; Eaton, Samuel W.; Marks, Tobin J.; Wasielewski, Michael R.

    2015-07-31

    The photophysics of a covalently linked perylenediimide–diketopyrrolopyrrole–perylenediimide acceptor–donor–acceptor molecule (PDI–DPP–PDI, 1) were investigated and found to be markedly different in solution versus in unannealed and solvent annealed films. Photoexcitation of 1 in toluene results in quantitative charge separation in τ = 3.1 ± 0.2 ps, with charge recombination in τ = 340 ± 10 ps, while in unannealed/disordered films of 1, charge separation occurs in τ < 250 fs, while charge recombination displays a multiexponential decay in ~6 ns. The absence of long-lived, charge separation in the disordered film suggests that few free charge carriers are generated. In contrast, uponmore » CH₂Cl₂ vapor annealing films of 1, grazing-incidence X-ray scattering shows that the molecules form a more ordered structure. Photoexcitation of the ordered films results in initial formation of a spin-correlated radical ion pair (electron–hole pair) as indicated by magnetic field effects on the formation of free charge carriers which live for ~4 μs. This result has significant implications for the design of organic solar cells based on covalent donor–acceptor systems and shows that long-lived, charge-separated states can be achieved by controlling intramolecular charge separation dynamics in well-ordered systems.« less

  12. Reactions of small molecular systems

    SciTech Connect (OSTI)

    Wittig, C.

    1993-12-01

    This DOE program remains focused on small molecular systems relevant to combustion. Though a number of experimental approaches and machines are available for this research, the authors` activities are centered around the high-n Rydberg time-of-flight (HRTOF) apparatus in this laboratory. One student and one postdoc carry out experiments with this machine and also engage in small intra-group collaborations involving shared equipment. This past year was more productive than the previous two, due to the uninterrupted operation of the HRTOF apparatus. Results were obtained with CH{sub 3}OH, CH{sub 3}SH, Rg-HX complexes, HCOOH, and their deuterated analogs where appropriate. One paper is in print, three have been accepted for publication, and one is under review. Many preliminary results that augur well for the future were obtained with other systems such as HNO{sub 3}, HBr-HI complexes, toluene, etc. Highlights from the past year are presented below that display some of the features of this program.

  13. Solid-state organometallic chemistry of molecular metal oxide clusters: C-H activation by an iridium polyoxometalate

    SciTech Connect (OSTI)

    Siedle, A.R.; Newmark, R.A.; Brown-Wensley, K.A.; Skarjune, R.P.; Haddad, L.C.; Hodgson, K.O.; Roe, A.L.

    1988-09-01

    Hydrogenation of ((Ph/sub 3/P)/sub 2/Ir(C/sub 8/H/sub 12/))/sub 3/PW/sub 12/O/sub 40/ in a solid-gas reaction produces ((Ph/sub 3/P)/sub 2/IrH/sub 2/)/sub 3/PW/sub 12/O/sub 40/. EXAFS studies of the molybdenum analogue indicate the presence of isolated, lattice-stabilized (Ph/sub 3/P)/sub 2/IrH/sub 2//sup +/ ions. H/emdash/D exchange with CD/sub 3/CH/double bond/CH/sub 2/ occurs via a reversible C/emdash/H addition reaction that also produces ((Ph/sub 3/P)/sub 2/IrH(/pi/-C/sub 3/H/sub 5/))/sub 3/PW/sub 12/O/sub 40/ and scrambles the C/sub 3/D/sub 3/H/sub 3/ deuterium label. Exchange with toluene is selective and involves activation of aromatic but not aliphatic C-H bonds. Slow exchange with c-C/sub 6/D/sub 12/ also occurs.

  14. Long-lived charge carrier generation in ordered films of a covalent perylenediimide–diketopyrrolopyrrole–perylenediimide molecule

    SciTech Connect (OSTI)

    Hartnett, Patrick E.; Dyar, Scott M.; Margulies, Eric A.; Shoer, Leah E.; Cook, Andrew W.; Eaton, Samuel W.; Marks, Tobin J.; Wasielewski, Michael R.

    2015-07-31

    The photophysics of a covalently linked perylenediimide–diketopyrrolopyrrole–perylenediimide acceptor–donor–acceptor molecule (PDI–DPP–PDI, 1) were investigated and found to be markedly different in solution versus in unannealed and solvent annealed films. Photoexcitation of 1 in toluene results in quantitative charge separation in τ = 3.1 ± 0.2 ps, with charge recombination in τ = 340 ± 10 ps, while in unannealed/disordered films of 1, charge separation occurs in τ < 250 fs, while charge recombination displays a multiexponential decay in ~6 ns. The absence of long-lived, charge separation in the disordered film suggests that few free charge carriers are generated. In contrast, upon CH₂Cl₂ vapor annealing films of 1, grazing-incidence X-ray scattering shows that the molecules form a more ordered structure. Photoexcitation of the ordered films results in initial formation of a spin-correlated radical ion pair (electron–hole pair) as indicated by magnetic field effects on the formation of free charge carriers which live for ~4 μs. This result has significant implications for the design of organic solar cells based on covalent donor–acceptor systems and shows that long-lived, charge-separated states can be achieved by controlling intramolecular charge separation dynamics in well-ordered systems.

  15. Absence of respiratory effects in subjects exposed to low concentrations of TDI and MDI

    SciTech Connect (OSTI)

    Musk, A.W.; Peters, J.M.; DiBerardinis, L.; Murphy, R.L.

    1982-10-01

    One hundred seven subjects from a polyurethane plastic manufacturing plant have been followed over a five-year period with measurements of forced expiratory volume in 1 s (FEV1), and questionnaires on respiratory symptoms and smoking habits. Environmental concentrations of toluene diisocyanate and diphenyl methyl diisocyanate were extensively monitored to provide accurate estimates of the upper-limits of exposure of the subjects. Current mean levels of FEV1 in this population were higher than those predicted for healthy subjects. The five-year change in FEV1 did not exceed that expected from aging. No acute change in FEV1 could be demonstrated over the course of a Monday either before or after a two-week vacation. No improvement in ventilatory function was observed over the vacation period. The presence of cough or sputum was related to smoking but was not related to isocyanate exposure. The results indicate that exposure of workers to extremely low levels of isocyanates (time-weighted average concentrations of the order of 0.001 parts per million (ppm)) is not associated with chronic respiratory symptoms or effects on ventilatory capacity. The results suggest that isocyanates can be controlled to the point of eliminating effects as measured by these techniques.

  16. Cometabolic bioremediation

    SciTech Connect (OSTI)

    Hazen, Terry C.

    2009-02-15

    Cometabolic bioremediation is probably the most under appreciated bioremediation strategy currently available. Cometabolism strategies stimulate only indigenous microbes with the ability to degrade the contaminant and cosubstrate e.g. methane, propane, toluene and others. This highly targeted stimulation insures that only those microbes that can degrade the contaminant are targeted, thus reducing amendment costs, well and formation plugging, etc. Cometabolic bioremediation has been used on some of the most recalcitrant contaminants, e.g. PCE, TCE, MTBE, TNT, dioxane, atrazine, etc. Methanotrophs have been demonstrated to produce methane monooxygense, an oxidase that can degrade over 300 compounds. Cometabolic bioremediation also has the advantage of being able to degrade contaminants to trace concentrations, since the biodegrader is not dependent on the contaminant for carbon or energy. Increasingly we are finding that in order to protect human health and the environment that we must remediate to lower and lower concentrations, especially for compounds like endocrine disrupters, thus cometabolism may be the best and maybe the only possibility that we have to bioremediate some contaminants.

  17. Hydroxylation of p-substituted phenols by tyrosinase: Further insight into the mechanism of tyrosinase activity

    SciTech Connect (OSTI)

    Munoz-Munoz, Jose Luis; Berna, Jose; Garcia-Molina, Maria del Mar; Garcia-Molina, Francisco; Garcia-Ruiz, Pedro Antonio; Varon, Ramon [Departamento de Quimica-Fisica, Escuela de Ingenieros Industriales de Albacete, Universidad de Castilla la Mancha, Avda. Espana s and others

    2012-07-27

    Highlights: Black-Right-Pointing-Pointer The action the copper complexes and tyrosinase on phenols is equivalent. Black-Right-Pointing-Pointer Isotope effect showed that nucleophilic attack to copper atom may be the slower step. Black-Right-Pointing-Pointer The value of {rho} (Hammett constant) supports an electrophilic aromatic substitution. Black-Right-Pointing-Pointer Data obtained in steady state pH 7 conditions support the mechanism of Scheme 1SM. -- Abstract: A study of the monophenolase activity of tyrosinase by measuring the steady state rate with a group of p-substituted monophenols provides the following kinetic information: k{sub cat}{sup m} and the Michaelis constant, K{sub M}{sup m}. Analysis of these data taking into account chemical shifts of the carbon atom supporting the hydroxyl group ({delta}) and {sigma}{sub p}{sup +}, enables a mechanism to be proposed for the transformation of monophenols into o-diphenols, in which the first step is a nucleophilic attack on the copper atom on the form E{sub ox} (attack of the oxygen of the hydroxyl group of C-1 on the copper atom) followed by an electrophilic attack (attack of the hydroperoxide group on the ortho position with respect to the hydroxyl group of the benzene ring, electrophilic aromatic substitution with a reaction constant {rho} of -1.75). These steps show the same dependency on the electronic effect of the substituent groups in C-4. Furthermore, a study of a solvent deuterium isotope effect on the oxidation of monophenols by tyrosinase points to an appreciable isotopic effect. In a proton inventory study with a series of p-substituted phenols, the representation of k{sub cat}{sup f{sub n}}/k{sub cat}{sup f{sub 0}} against n (atom fractions of deuterium), where k{sub cat}{sup f{sub n}} is the catalytic constant for a molar fraction of deuterium (n) and k{sub cat}{sup f{sub 0}} is the corresponding kinetic parameter in a water solution, was linear for all substrates. These results indicate that only one of the proton transfer processes from the hydroxyl groups involved the catalytic cycle is responsible for the isotope effects. We suggest that this step is the proton transfer from the hydroxyl group of C-1 to the peroxide of the oxytyrosinase form (E{sub ox}). After the nucleophilic attack, the incorporation of the oxygen in the benzene ring occurs by means of an electrophilic aromatic substitution mechanism in which there is no isotopic effect.

  18. 2D?3D polycatenated and 3D?3D interpenetrated metal–organic frameworks constructed from thiophene-2,5-dicarboxylate and rigid bis(imidazole) ligands

    SciTech Connect (OSTI)

    Erer, Hakan; Ye?ilel, Okan Zafer; Ar?c?, Mürsel; Keskin, Seda; Büyükgüngör, Orhan

    2014-02-15

    Hydrothermal reactions of rigid 1,4-bis(imidazol-1-yl)benzene (dib) and 1,4-bis(imidazol-1-yl)-2,5-dimethylbenzene (dimb) with deprotonated thiophene-2,5-dicarboxylic acid (H{sub 2}tdc) in the presence of Zn(II) and Cd(II) salts in H{sub 2}O produced three new metal–organic frameworks, namely, [Zn(µ-tdc)(H{sub 2}O)(µ-dib)]{sub n} (1), [Cd(µ-tdc)(H{sub 2}O)(µ-dib)]{sub n} (2), and ([Cd{sub 2}(µ{sub 3}-tdc){sub 2}(µ-dimb){sub 2}]·(H{sub 2}O)){sub n}(3). These MOFs were characterized by FT-IR spectroscopy, elemental, thermal (TG, DTA, DTG and DSC), and single-crystal X-ray diffraction analyses. Isomorphous complexes 1 and 2 reveal polycatenated 2D+2D?3D framework based on an undulated (4,4)-sql layer. Complex 3 exhibits a new 4-fold interpenetrating 3D framework with the point symbol of 6{sup 6}. Molecular simulations were used to assess the potentials of the complexes for H{sub 2} storage application. Moreover, these coordination polymers exhibit blue fluorescent emission bands in the solid state at room temperature. - Graphical abstract: In this study, hydrothermal reactions of rigid 1,4-bis(imidazol-1-yl)benzene (dib) and 1,4-bis(imidazol-1-yl)-2,5-dimethylbenzene (dimb) with deprotonated thiophene-2,5-dicarboxylic acid (H{sub 2}tdc) in the presence of Zn(II) and Cd(II) salts in H{sub 2}O produced three new metal–organic frameworks. Isomorphous complexes 1 and 2 reveal polycatenated 2D+2D?3D framework based on an undulated (4,4)-sql layer. Complex 3 exhibits a new 4-fold interpenetrating 3D framework with the point symbol of 6{sup 6}. Molecular simulations were used to assess the potentials of the complexes for H{sub 2} storage application. These coordination polymers exhibit blue fluorescent emission bands in the solid state at room temperature. Display Omitted - Highlights: • Complexes 1 and 2 display polycatenated 2D+2D?3D framework. • Complex 3 exhibits a new 4-fold interpenetrating 3D framework. • Complex 1 adsorbs the highest amount of H{sub 2} at 100 bar and 298 K. • Complexes display blue fluorescent emission bands.

  19. Health and Environmental Effects Document on Geothermal Energy -- 1982 update

    SciTech Connect (OSTI)

    Layton, David W.; Daniels, Jeffrey I.; Anspaugh, Lynn R.; O'Banion, Kerry D.

    1983-11-30

    We assess several of the important health and environmental risks associated with a reference geothermal industry that produces 21,000 MWe for 30 y (equivalent to 20 x 10{sup 18} J). The analyses of health effects focus on the risks associated with exposure to hydrogen sulfide, particulate sulfate, benzene, mercury, and radon in air and arsenic in food. Results indicate that emissions of hydrogen sulfide are likely to cause odor-related problems in 29 of 51 geothermal resources areas, assuming that no pollution controls are employed. Our best estimates and ranges of uncertainty for the health risks of chronic population exposures to atmospheric pollutants are as follows (risks expressed per 10{sup 18} J of electricity): particulate sulfate, 44 premature deaths (uncertainty range of 0 to 360); benzene, 0.15 leukemias (range of 0 to 0.51); elemental mercury, 14 muscle tremors (range of 0 to 39); and radon, 0.68 lung cancers (range of 0 to 1.8). The ultimate risk of fatal skin cancers as the result of the transfer of waste arsenic to the general population over geologic time ({approx} 100,000 y) was calculated as 41 per 10{sup 18} J. We based our estimates of occupational health effects on rates of accidental deaths together with data on occupational diseases and injuries in surrogate industries. According to our best estimates, there would be 8 accidental deaths per 10{sup 18} J of electricity, 300 cases of occupational diseases per 10{sup 18} J, and 3400 occupational injuries per 10{sup 18}J. The analysis of the effects of noncondensing gases on vegetation showed that ambient concentrations of hydrogen sulfide and carbon dioxide are more likely to enhance rather than inhibit the growth of plants. We also studied the possible consequences of accidental releases of geothermal fluids and concluded that probably less than 5 ha of land would be affected by such releases during the production of 20 x 10{sup 18} J of electricity. Boron emitted from cooling towers in the Imperial Valley was identified as a potential source of crop damage. Our analyses, however, showed that such damage is unlikely. Finally, we examined the nonpollutant effects of land subsidence and induced seismicity. Land subsidence is possible around some facilities, but surface-related damage is not expected to be great. Induced seismic events that have occurred to date at geothermal resource areas have been nondestructive. It is not possible to predict accurately the risk of potentially destructive events, and more research is needed in this area.

  20. Coupled electron-nuclear dynamics: Charge migration and charge transfer initiated near a conical intersection

    SciTech Connect (OSTI)

    Mendive-Tapia, David; Vacher, Morgane; Bearpark, Michael J.; Robb, Michael A.

    2013-07-28

    Coupled electron-nuclear dynamics, implemented using the Ehrenfest method, has been used to study charge migration with fixed nuclei, together with charge transfer when nuclei are allowed to move. Simulations were initiated at reference geometries of neutral benzene and 2-phenylethylamine (PEA), and at geometries close to potential energy surface crossings in the cations. Cationic eigenstates, and the so-called sudden approximation, involving removal of an electron from a correlated ground-state wavefunction for the neutral species, were used as initial conditions. Charge migration without coupled nuclear motion could be observed if the Ehrenfest simulation, using the sudden approximation, was started near a conical intersection where the states were both strongly coupled and quasi-degenerate. Further, the main features associated with charge migration were still recognizable when the nuclear motion was allowed to couple. In the benzene radical cation, starting from the reference neutral geometry with the sudden approximation, one could observe sub-femtosecond charge migration with a small amplitude, which results from weak interaction with higher electronic states. However, we were able to engineer large amplitude charge migration, with a period between 10 and 100 fs, corresponding to oscillation of the electronic structure between the quinoid and anti-quinoid cationic electronic configurations, by distorting the geometry along the derivative coupling vector from the D{sub 6h} Jahn-Teller crossing to lower symmetry where the states are not degenerate. When the nuclear motion becomes coupled, the period changes only slightly. In PEA, in an Ehrenfest trajectory starting from the D{sub 2} eigenstate and reference geometry, a partial charge transfer occurs after about 12 fs near the first crossing between D{sub 1}, D{sub 2} (N{sup +}-Phenyl, N-Phenyl{sup +}). If the Ehrenfest propagation is started near this point, using the sudden approximation without coupled nuclear motion, one observes an oscillation of the spin density – charge migration – between the N atom and the phenyl ring with a period of 4 fs. When the nuclear motion becomes coupled, this oscillation persists in a damped form, followed by an effective charge transfer after 30 fs.