National Library of Energy BETA

Sample records for aromatic hydrocarbon pah

  1. Distribution of polycyclic aromatic hydrocarbons (PAH's) in marsh sediments, Iraq

    SciTech Connect (OSTI)

    Al-Saad, H.T.; Al-Timari, A.A. )

    1989-12-01

    Recently there has been a growing concern in the release of harmful organics into the environment. Carcinogenic polycyclic aromatic hydrocarbons (PAH's) are a class of compounds of interset due to their possible harmful effects to man as well as organisms. Anthropogenic PAH's may reach aquatic environment as a result of both industrial and domestic effluents, deposition of airborne particles, surface runoff and oil spillage. Having a relatively low water solubility and high affinity to sorb to the suspended particulate matter, most of the PAH's introduced to the aquatic environment tend to accumulate in bottom sediments. Sedimentary PAH's may thus provide a record of the input and history of these pollutants. Consequently, the distribution of PAH's in aquatic sediments have received considerable attention. The purpose of the present work was to establish the distribution of PAH's in the sediments of the marsh region located in southern Iraq.

  2. Polycyclic aromatic hydrocarbons (PAH) formation from the pyrolysis of different municipal solid waste fractions

    SciTech Connect (OSTI)

    Zhou, Hui; Wu, Chunfei; Onwudili, Jude A.; Meng, Aihong; Zhang, Yanguo; Williams, Paul T.

    2015-02-15

    Highlights: • PAH from pyrolysis of 9 MSW fractions was investigated. • Pyrolysis of plastics released more PAH than that of biomass. • Naphthalene was the most abundant PAH in the tar. • The mechanism of PAH release from biomass and plastics was proposed. - Abstract: The formation of 2–4 ring polycyclic aromatic hydrocarbons (PAH) from the pyrolysis of nine different municipal solid waste fractions (xylan, cellulose, lignin, pectin, starch, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET)) were investigated in a fixed bed furnace at 800 °C. The mass distribution of pyrolysis was also reported. The results showed that PS generated the most total PAH, followed by PVC, PET, and lignin. More PAH were detected from the pyrolysis of plastics than the pyrolysis of biomass. In the biomass group, lignin generated more PAH than others. Naphthalene was the most abundant PAH, and the amount of 1-methynaphthalene and 2-methynaphthalene was also notable. Phenanthrene and fluorene were the most abundant 3-ring PAH, while benzo[a]anthracene and chrysene were notable in the tar of PS, PVC, and PET. 2-ring PAH dominated all tar samples, and varied from 40 wt.% to 70 wt.%. For PS, PET and lignin, PAH may be generated directly from the aromatic structure of the feedstock.

  3. Polycyclic aromatic hydrocarbons (PAHs): a possible cause of lung cancer mortality among nickel/copper smelter and refinery workers

    SciTech Connect (OSTI)

    Verma, D.K.; Julian, J.A.; Roberts, R.S.; Muir, D.C.; Jadon, N.; Shaw, D.S. )

    1992-05-01

    A retrospective industrial hygiene investigation was undertaken to explain the cause of a statistically significant excess lung cancer mortality observed in a subset of a large cohort of nickel workers involved in mining, smelting, and refining of nickel and copper in Ontario. The focus of this paper is to demonstrate how an industrial hygiene follow-up assessment of an epidemiologic finding can help to identify a likely cause. Polycyclic aromatic hydrocarbons (PAHs) alone or in association with particulate and gaseous contaminants (e.g., SO2) were likely the causative agents of the excess lung cancer observed among the lead welders, cranemen, and arc furnace workers of the copper refinery.

  4. Properties of polycyclic aromatic hydrocarbons in the northwest photon dominated region of NGC 7023. II. Traditional PAH analysis using k-means as a visualization tool

    SciTech Connect (OSTI)

    Boersma, C.; Bregman, J.; Allamandola, L. J.

    2014-11-10

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer-IRS spectral map of the northwest photon dominated region (PDR) in NGC 7023 is analyzed using the 'traditional' approach in which the PAH bands and plateaus between 5.2-19.5 μm are isolated by subtracting the underlying continuum and removing H{sub 2} emission lines. The spectra are organized into seven spectroscopic bins by using k-means clustering. Each cluster corresponds to, and reveals, a morphological zone within NGC 7023. The zones self-organize parallel to the well-defined PDR front that coincides with an increase in intensity of the H{sub 2} emission lines. PAH band profiles and integrated strengths are measured, classified, and mapped. The morphological zones revealed by the k-means clustering provides deeper insight into the conditions that drive variations in band strength ratios and evolution of the PAH population that otherwise would be lost. For example, certain band-band relations are bifurcated, revealing two limiting cases; one associated with the PDR, the other with the diffuse medium. Traditionally, PAH band strength ratios are used to gain insight into the properties of the emitting PAH population, i.e., charge, size, structure, and composition. Insights inferred from this work are compared and contrasted to those from Boersma et al. (first paper in this series), where the PAH emission in NGC 7023 is decomposed exclusively using the PAH spectra and tools made available through the NASA Ames PAH IR Spectroscopic Database.

  5. Estimating the in situ sediment-porewater distribution of PAHs and chlorinated aromatic hydrocarbons in anthropogenic impacted sediments

    SciTech Connect (OSTI)

    Hans Peter H. Arp; Gijs D. Breedveld; Gerard Cornelissen

    2009-08-15

    It has become increasingly apparent that the in situ sediment-porewater distribution behavior of organic compounds within anthropogenic impacted sediments is quite diverse, and challenging to generalize. Traditional models based on octanol-water partitioning generally overestimate native porewater concentrations, and modern approaches accounting for multiple carbon fractions, including black carbon, appear sediment specific. To assess the diversity of this sorption behavior, we collected all peer-reviewed total organic carbon (TOC)-normalized in situ sediment-porewater distribution coefficients, K{sub TOC}, for impacted sediments. This entailed several hundreds of data for PAHs, PCBs, PCDD/Fs, and chlorinated benzenes, covering a large variety of sediments, locations, and experimental methods. Compound-specific KTOC could range up to over 3 orders of magnitude. Output from various predictive models for individual carbonaceous phases found in impacted sediments, based on peer-reviewed polyparameter linear free energy relationships (PP-LFERs), Raoult's Law, and the SPARC online-calculator, were tested to see if any of the models could consistently predict literature K{sub TOC} values within a factor of 30 (i.e. about 1.5 orders of magnitude, or half the range of K{sub TOC} values). The Raoult's Law model and coal tar PP-LFER achieved the sought-after accuracy for all tested compound classes, and are recommended for general, regional-scale modeling purposes. As impacted sediment-porewater distribution models are unlikely to get more accurate than this, this review underpins that the only way to accurately obtain accurate porewater concentrations is to measure them directly, and not infer them from sediment concentrations. 86 refs., 2 figs., 3 tabs.

  6. THE INFRARED SPECTROSCOPY OF NEUTRAL POLYCYCLIC AROMATIC HYDROCARBON CLUSTERS

    SciTech Connect (OSTI)

    Ricca, Alessandra; Bauschlicher, Charles W. Jr.; Allamandola, Louis J. E-mail: Charles.W.Bauschlicher@nasa.gov

    2013-10-10

    The mid-infrared spectra of neutral homogeneous polycyclic aromatic hydrocarbon (PAH) clusters have been computed using density functional theory including an empirical correction for dispersion. The C-H out-of-plane bending modes are redshifted for all the clusters considered in this work. The magnitude of the redshift and the peak broadening are dependent on PAH size, shape, and on the PAH arrangement in the cluster.

  7. Simulation of polycyclic aromatic hydrocarbons transport in multimedia

    SciTech Connect (OSTI)

    Chen, L.; Chu, C.J.

    1999-07-01

    Many studies have indicated that the threat from toxic air pollutants such as VOCs comes not through inhalation by humans while the pollutants are in a gaseous state but through absorption when the pollutants are in a solid state such as in an aerosol or particulate form. Pollutants such as Polycyclic Aromatic Hydrocarbons (PAHs) usually exist in a semi-volatile state. To assess the risk of the PAHs, one needs to estimate the dose of the pollutants to which a human would be exposed through various pathways. In this study, the authors modified a Spatial Multimedia Compartmental Model (SMCM) originally developed by UCLA Professor Cohen to predict the PAHs distribution among multimedia such as air, water, soil and sediment in the Taipei metropolitan area. Three PAHs were considered in this study. They are Benzo(a)pyrene, Pyrene and Chrysene. When PAHs are emitted into atmosphere, physical and chemical mechanisms may redistribute the PAHs among multimedia. Five cases of PAHs distribution in multimedia were simulated: (1) PAHs distribution in a dry condition, (2) PAHs distribution when there are different dry deposition velocities, (3) PAHs distribution under a single rainfall event, (4) PAHs distribution when there are different soil properties, (5) PAHs distribution under a random rainfall case. The simulation results are concluded: (1) In the dry case, the PAHs accumulate mostly in soil and air compartments, (2) Different dry depositing velocities will affect the PAHs distribution among compartments. (3) Different soil properties affect the PAHs concentration in the soil and sediment compartments, (4) The soil PAHs concentrations usually increase for those PAHs with a high solid/gas ratio. (5) The random rainfall only affects the PAHs concentration in the soil.

  8. 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.

  9. Atmospheric transport and outflow of polycyclic aromatic hydrocarbons from China

    SciTech Connect (OSTI)

    Chang Lang; Shu Tao; Wenxin Liu; Yanxu Zhang; Staci Simonich

    2008-07-15

    A potential receptor influence function (PRIF) model, based on air mass forward trajectory calculations, was applied to simulate the atmospheric transport and outflow of polycyclic aromatic hydrocarbons (PAHs) emitted from China. With a 10 day atmospheric transport time, most neighboring countries and regions, as well as remote regions, were influenced by PAH emissions from China. Of the total annual PAH emission of 114 Gg, 92.7% remained within the boundary of mainland China. The geographic distribution of PRIFs within China was similar to the geographic distribution of the source regions, with high values in the North China Plain, Sichuan Basin, Shanxi, and Guizhou province. The Tarim basin and Sichuan basin had unfavorable meteorological conditions for PAH outflow. Of the PAH outflow from China (8092 tons or 7.1% of the total annual PAH emission), approximately 69.9% (5655 tons) reached no further than the offshore environment of mainland China and the South China Sea. Approximate 227, 71, 746, and 131 tons PAHs reached North Korea, South Korea, Russia-Mongolia region, and Japan, respectively, 2-4 days after the emission. Only 1.4 tons PAHs reached North America after more than 9 days. Interannual variation in the eastward PAH outflow was positively correlated to cold episodes of El Nino/Southern Oscillation. However, trans-Pacific atmospheric transport of PAHs from China was correlated to Pacific North America index (PNA) which is associated with the strength and position of westerly winds. 38 refs., 4 figs.

  10. 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.

  11. 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.

  12. Molecular catalytic hydrogenation of aromatic hydrocarbons and

    Office of Scientific and Technical Information (OSTI)

    catalytic hydrogenation of aromatic hydrocarbons and hydrotreating of coal liquids. Yang, Shiyong; Stock, L.M. 01 COAL, LIGNITE, AND PEAT; 40 CHEMISTRY; COAL LIQUIDS;...

  13. Molecular catalytic hydrogenation of aromatic hydrocarbons and...

    Office of Scientific and Technical Information (OSTI)

    and hydrotreating of coal liquids. Citation Details In-Document Search Title: Molecular catalytic hydrogenation of aromatic hydrocarbons and hydrotreating of coal liquids. ...

  14. LARGE ABUNDANCES OF POLYCYCLIC AROMATIC HYDROCARBONS IN TITAN'S UPPER ATMOSPHERE

    SciTech Connect (OSTI)

    Lopez-Puertas, M.; Funke, B.; Garcia-Comas, M.; Dinelli, B. M.; Adriani, A.; D'Aversa, E.; Moriconi, M. L.; Boersma, C.; Allamandola, L. J.

    2013-06-20

    In this paper, we analyze the strong unidentified emission near 3.28 {mu}m in Titan's upper daytime atmosphere recently discovered by Dinelli et al. We have studied it by using the NASA Ames PAH IR Spectroscopic Database. The polycyclic aromatic hydrocarbons (PAHs), after absorbing UV solar radiation, are able to emit strongly near 3.3 {mu}m. By using current models for the redistribution of the absorbed UV energy, we have explained the observed spectral feature and have derived the vertical distribution of PAH abundances in Titan's upper atmosphere. PAHs have been found to be present in large concentrations, about (2-3) Multiplication-Sign 10{sup 4} particles cm{sup -3}. The identified PAHs have 9-96 carbons, with a concentration-weighted average of 34 carbons. The mean mass is {approx}430 u; the mean area is about 0.53 nm{sup 2}; they are formed by 10-11 rings on average, and about one-third of them contain nitrogen atoms. Recently, benzene together with light aromatic species as well as small concentrations of heavy positive and negative ions have been detected in Titan's upper atmosphere. We suggest that the large concentrations of PAHs found here are the neutral counterpart of those positive and negative ions, which hence supports the theory that the origin of Titan main haze layer is located in the upper atmosphere.

  15. Distribution of polycyclic aromatic hydrocarbons in lime spray dryer ash

    SciTech Connect (OSTI)

    Ping Sun; Panuwat Taerakul; Linda K. Weavers; Harold W. Walker

    2005-10-01

    Four lime spray dryer (LSD) ash samples were collected from a spreader stoker boiler and measured for their concentrations of 16 U.S. EPA specified polycyclic aromatic hydrocarbons (PAHs). Results showed that the total measured PAH concentration correlated with the organic carbon content of the LSD ash. Each LSD ash sample was then separated using a 140 mesh sieve into two fractions: a carbon-enriched fraction ({gt}140 mesh) and a lime-enriched fraction ({lt}140 mesh). Unburned carbon was further separated from the carbon-enriched fraction with a lithiumheteropolytungstate (LST) solution. PAH measurements on these different fractions showed that unburned carbon had the highest PAH concentrations followed by the carbon-enriched fraction, indicating that PAHs were primarily associated with the carbonaceous material in LSD ash. However, detectable levels of PAHs were also found in the lime-enriched fraction, suggesting that the fine spray of slaked lime may sorb PAH compounds from the flue gas in the LSD process. 37 refs., 5 figs., 4 tabs.

  16. Polynuclear aromatic hydrocarbons for fullerene synthesis in flames

    DOE Patents [OSTI]

    Alford, J. Michael; Diener, Michael D.

    2006-12-19

    This invention provides improved methods for combustion synthesis of carbon nanomaterials, including fullerenes, employing multiple-ring aromatic hydrocarbon fuels selected for high carbon conversion to extractable fullerenes. The multiple-ring aromatic hydrocarbon fuels include those that contain polynuclear aromatic hydrocarbons. More specifically, multiple-ring aromatic hydrocarbon fuels contain a substantial amount of indene, methylnapthalenes or mixtures thereof. Coal tar and petroleum distillate fractions provide low cost hydrocarbon fuels containing polynuclear aromatic hydrocarbons, including without limitation, indene, methylnapthalenes or mixtures thereof.

  17. DUSTY WINDS: EXTRAPLANAR POLYCYCLIC AROMATIC HYDROCARBON FEATURES OF NEARBY GALAXIES

    SciTech Connect (OSTI)

    McCormick, Alexander; Veilleux, Sylvain; Rupke, David S. N. E-mail: veilleux@astro.umd.edu

    2013-09-10

    Recent observations have shown the presence of dust and molecular material in galactic winds, but relatively little is known about the distribution of these outflow components. To shed some light on this issue, we have used IRAC images from the Spitzer Space Telescope archive to investigate polycyclic aromatic hydrocarbon (PAH) emission from a sample of 16 local galaxies with known winds. Our focus on nearby sources (median distance 8.6 Mpc) has revealed detailed PAH structure in the winds and allowed us to measure extraplanar PAH emission. We have identified extraplanar PAH features on scales of {approx}0.8-6.0 kpc. We find a nearly linear correlation between the amount of extraplanar PAH emission and the total infrared flux, a proxy for star formation activity in the disk. Our results also indicate a correlation between the height of extraplanar PAH emission and star formation rate surface density, which supports the idea of a surface density threshold on the energy or momentum injection rate for producing detectable extraplanar wind material.

  18. A study on the coagulation of polycyclic aromatic hydrocarbon clusters to determine their collision efficiency

    SciTech Connect (OSTI)

    Raj, Abhijeet; Sander, Markus; Janardhanan, Vinod; Kraft, Markus [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom)

    2010-03-15

    This paper presents a theoretical study on the physical interaction between polycyclic aromatic hydrocarbons (PAHs) and their clusters of different sizes in laminar premixed flames. Two models are employed for this study: a detailed PAH growth model, referred to as the kinetic Monte Carlo - aromatic site (KMC-ARS) model [Raj et al., Combust. Flame 156 (2009) 896-913]; and a multivariate PAH population balance model, referred to as the PAH - primary particle (PAH-PP) model. Both the models are solved by kinetic Monte Carlo methods. PAH mass spectra are generated using the PAH-PP model, and compared to the experimentally observed spectra for a laminar premixed ethylene flame. The position of the maxima of PAH dimers in the spectra and their concentrations are found to depend strongly on the collision efficiency of PAH coagulation. The variation in the collision efficiency with various flame and PAH parameters is studied to determine the factors on which it may depend. A correlation for the collision efficiency is proposed by comparing the computed and the observed spectra for an ethylene flame. With this correlation, a good agreement between the computed and the observed spectra for a number of laminar premixed ethylene flames is found. (author)

  19. Measurement of polycyclic aromatic hydrocarbons in the air along the niagara river

    SciTech Connect (OSTI)

    Hoff, R.M.; Chan, K.W.

    1987-06-01

    Two week-long studies in 1982-1983 have measure ambient concentrations of polycyclic aromatic hydrocarbons (PAH) and phthalate esters in air in both the particulate and gas phase along the US-Canadian border and the Niagara River. Concentrations of the PAH species monitored varied from 3 pg m/sup -3/ to 40 ng m/sup -3/. PAH's with three rings or less were found in significant proportions in the gas phase while larger molecules are almost solely in the particulate phase. Particulate components of the PAH loadings appear to originate locally with Buffalo, NY, Niagara Falls, NY, and Niagara Falls, Ontario, as probably sources. Gas-phase PAH components have a more regional character indicating regional or long-range transport. Levels of benzo(a)pyrene are consistent with previous particulate measurements made along the river since 1981.

  20. Characterization of polycyclic aromatic hydrocarbons in motor vehicle fuels and exhaust emissions

    SciTech Connect (OSTI)

    Marr, L.C.; Kirchstetter, T.W.; Harley, R.A.; Hammond, S.K.; Miguel, A.H.; Hering, S.V.

    1999-09-15

    Motor vehicles are a significant source of polycyclic aromatic hydrocarbon (PAH) emissions. Improved understanding of the relationship between fuel composition and PAH emissions is needed to determine whether fuel reformulation is a viable approach for reducing PAH emissions. PAH concentrations were quantified in gasoline and diesel fuel samples collected in summer 1997 in northern California. Naphthalene was the predominant PAH in both fuels, with concentrations of up to 2,600 mg L{sup {minus}1} in gasoline and 1,600 mg L{sup {minus}1} in diesel fuel. Particle-phase PAH size distributions and exhaust emission factors were measured in two bores of a roadway tunnel. Emission factors were determined separately for light-duty vehicles and for heavy-duty diesel trucks, based on measurements of PAHs, CO, and CO{sub 2}. Particle-phase emission factors, expressed per unit mass of fuel burned, ranged up to 21 {micro}g kg{sup {minus}1} for benzo[ghi]perylene for light-duty vehicles and up to {approximately} 1,000 {micro}g kg{sup {minus}1} for pyrene for heavy-duty diesel vehicles. Light-duty vehicles were found to be a significant source of heavier (four- and five-ring) PAHs, whereas heavy-duty diesel engines were the dominant source of three-ring PAHs, such as fluoranthene and pyrene. While no correlation between heavy-duty diesel truck PAH emission factors and PAH concentrations in diesel fuel was found, light-duty vehicle PAH emission factors were found to be correlated with PAH concentrations in gasoline, suggesting that gasoline reformulation may be effective in reducing PAH emissions from motor vehicles.

  1. Monitoring of vapor phase polycyclic aromatic hydrocarbons

    DOE Patents [OSTI]

    Vo-Dinh, Tuan; Hajaligol, Mohammad R.

    2004-06-01

    An apparatus for monitoring vapor phase polycyclic aromatic hydrocarbons in a high-temperature environment has an excitation source producing electromagnetic radiation, an optical path having an optical probe optically communicating the electromagnetic radiation received at a proximal end to a distal end, a spectrometer or polychromator, a detector, and a positioner coupled to the first optical path. The positioner can slidably move the distal end of the optical probe to maintain the distal end position with respect to an area of a material undergoing combustion. The emitted wavelength can be directed to a detector in a single optical probe 180.degree. backscattered configuration, in a dual optical probe 180.degree. backscattered configuration or in a dual optical probe 90.degree. side scattered configuration. The apparatus can be used to monitor an emitted wavelength of energy from a polycyclic aromatic hydrocarbon as it fluoresces in a high temperature environment.

  2. Characterization and analysis of polycyclic aromatic hydrocarbons

    SciTech Connect (OSTI)

    Breuer, G.M.; Smith, J.P.

    1984-01-01

    Sampling and analytical procedures were developed for determining the concentrations of polycyclic aromatic hydrocarbons in animal-exposure chambers during studies on exposure to diesel exhaust, coal dust, or mixtures of these two pollutants. Fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(e)pyrene, benzo(k)fluoranthene, and benzo(a)pyrene were used as representative polycyclic aromatic hydrocarbons. High-pressure liquid chromatography with fluorescence detection was used for analysis. Coal-dust only samples revealed a broad, rising background in the chromatogram with small peaks superimposed corresponding to fluoranthene, pyrene, and benzo(a)anthracene, diesel exhaust only samples showed many peaks on a flat baseline including those corresponding to fluoranthene, pyrene, benzo(a)anthracene, benzo(k)fluoranthene, and benzo(a)pyrene. In general, no polynuclear aromatics were noted in the clean air samples. The authors note that relatively minor changes in air/fuel ratio, lubricant, fuel, and load may have substantial effects on very minor components of the exhaust emission.

  3. Ligand-specific transcriptional mechanisms underlie aryl hydrocarbon receptor-mediated developmental toxicity of oxygenated PAHs

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

    Goodale, B. C.; Geisel School of Medicine at Dartmouth, Hanover, NH; La Du, J.; Tilton, S. C.; Pacific Northwest National Lab.; Sullivan, C. M.; Bisson, W. H.; Waters, K. M.; Tanguay, R. L.

    2015-07-03

    Polycyclic aromatic hydrocarbons (PAHs) are priority environmental contaminants that exhibit mutagenic, carcinogenic, proinflammatory, and teratogenic properties. Oxygen-substituted PAHs (OPAHs) are formed during combustion processes and via phototoxidation and biological degradation of parent (unsubstituted) PAHs. Despite their prevalence both in contaminated industrial sites and in urban air, OPAH mechanisms of action in biological systems are relatively understudied. Like parent PAHs, OPAHs exert structure-dependent mutagenic activities and activation of the aryl hydrocarbon receptor (AHR) and cytochrome p450 metabolic pathway. Four-ring OPAHs 1,9-benz-10-anthrone (BEZO) and benz(a)anthracene-7,12-dione (7,12-B[a]AQ) cause morphological aberrations and induce markers of oxidative stress in developing zebrafish with similar potency, butmore » only 7,12-B[a]AQ induces robust Cyp1a protein expression. We investigated the role of the AHR in mediating the toxicity of BEZO and 7,12-B[a]AQ, and found that knockdown of AHR2 rescued developmental effects caused by both compounds. Using RNA-seq and molecular docking, we identified transcriptional responses that precede developmental toxicity induced via differential interaction with AHR2. Redox-homeostasis genes were affected similarly by these OPAHs, while 7,12-B[a]AQ preferentially activated phase 1 metabolism and BEZO uniquely decreased visual system genes. Analysis of biological functions and upstream regulators suggests that BEZO is a weak AHR agonist, but interacts with other transcriptional regulators to cause developmental toxicity in an AHR-dependent manner. Furthermore, identifying ligand-dependent AHR interactions and signaling pathways is essential for understanding toxicity of this class of environmentally relevant compounds.« less

  4. Ligand-specific transcriptional mechanisms underlie aryl hydrocarbon receptor-mediated developmental toxicity of oxygenated PAHs

    SciTech Connect (OSTI)

    Goodale, B. C.; La Du, J.; Tilton, S. C.; Sullivan, C. M.; Bisson, W. H.; Waters, K. M.; Tanguay, R. L.

    2015-07-03

    Polycyclic aromatic hydrocarbons (PAHs) are priority environmental contaminants that exhibit mutagenic, carcinogenic, proinflammatory, and teratogenic properties. Oxygen-substituted PAHs (OPAHs) are formed during combustion processes and via phototoxidation and biological degradation of parent (unsubstituted) PAHs. Despite their prevalence both in contaminated industrial sites and in urban air, OPAH mechanisms of action in biological systems are relatively understudied. Like parent PAHs, OPAHs exert structure-dependent mutagenic activities and activation of the aryl hydrocarbon receptor (AHR) and cytochrome p450 metabolic pathway. Four-ring OPAHs 1,9-benz-10-anthrone (BEZO) and benz(a)anthracene-7,12-dione (7,12-B[a]AQ) cause morphological aberrations and induce markers of oxidative stress in developing zebrafish with similar potency, but only 7,12-B[a]AQ induces robust Cyp1a protein expression. We investigated the role of the AHR in mediating the toxicity of BEZO and 7,12-B[a]AQ, and found that knockdown of AHR2 rescued developmental effects caused by both compounds. Using RNA-seq and molecular docking, we identified transcriptional responses that precede developmental toxicity induced via differential interaction with AHR2. Redox-homeostasis genes were affected similarly by these OPAHs, while 7,12-B[a]AQ preferentially activated phase 1 metabolism and BEZO uniquely decreased visual system genes. Analysis of biological functions and upstream regulators suggests that BEZO is a weak AHR agonist, but interacts with other transcriptional regulators to cause developmental toxicity in an AHR-dependent manner. Furthermore, identifying ligand-dependent AHR interactions and signaling pathways is essential for understanding toxicity of this class of environmentally relevant compounds.

  5. Synergistic effect of mixing dimethyl ether with methane, ethane, propane, and ethylene fuels on polycyclic aromatic hydrocarbon and soot formation

    SciTech Connect (OSTI)

    Yoon, S.S.; Anh, D.H.; Chung, S.H.

    2008-08-15

    Characteristics of polycyclic aromatic hydrocarbon (PAH) and soot formation in counterflow diffusion flames of methane, ethane, propane, and ethylene fuels mixed with dimethyl ether (DME) have been investigated. Planar laser-induced incandescence and fluorescence techniques were employed to measure relative soot volume fractions and PAH concentrations, respectively. Results showed that even though DME is known to be a clean fuel in terms of soot formation, DME mixture with ethylene fuel increases PAH and soot formation significantly as compared to the pure ethylene case, while the mixture of DME with methane, ethane, and propane decreases PAH and soot formation. Numerical calculations adopting a detailed kinetics showed that DME can be decomposed to produce a relatively large number of methyl radicals in the low-temperature region where PAH forms and grows; thus the mixture of DME with ethylene increases CH{sub 3} radicals significantly in the PAH formation region. Considering that the increase in the concentration of O radicals is minimal in the PAH formation region with DME mixture, the enhancement of PAH and soot formation in the mixture flames of DME and ethylene can be explained based on the role of methyl radicals in PAH and soot formation. Methyl radicals can increase the concentration of propargyls, which could enhance incipient benzene ring formation through the propargyl recombination reaction and subsequent PAH growth. Thus, the result substantiates the importance of methyl radicals in PAH and soot formation, especially in the PAH formation region of diffusion flames. (author)

  6. Trends in polycyclic aromatic hydrocarbon concentrations in the Great Lakes atmosphere

    SciTech Connect (OSTI)

    Ping Sun; Pierrette Blanchard; Kenneth A. Brice; Ronald A. Hites

    2006-10-15

    Atmospheric polycyclic aromatic hydrocarbon (PAHs) concentrations were measured in both the vapor and particle phases at seven sites near the Great Lakes as a part of the Integrated Atmospheric Deposition Network. Lower molecular weight PAHs, including fluorene, phenanthrene, fluoranthrene, and pyrene, were dominant in the vapor phase, and higher molecular weight PAHs, including chrysene, benzo(a)pyrene, and coronene, were dominant in the particle phase. The highest PAH concentrations in both the vapor and particle phases were observed in Chicago followed by the semiurban site at Sturgeon Point, NY. The major sources of PAHs in and around Chicago are vehicle emissions, coal and natural gas combustion, and coke production. The spatial difference of PAH concentrations can be explained by the local population density. Long-term decreasing trends of most PAH concentrations were observed in both the vapor and particle phases at Chicago, with half-lives ranging from 3-10 years in the vapor phase and 5-15 years in the particle phase. At Eagle Harbor, Sleeping Bear Dunes, and Sturgeon Point, total PAH concentrations in the vapor phase showed significant, but slow, long-term decreasing trends. At the Sturgeon Point site, which was impacted by a nearby city, particle-phase PAH concentrations also declined. However, most particle-phase PAH concentrations did not show significant long-term decreasing trends at the remote sites. Seasonal trends were also observed for particle-phase PAH concentrations, which were higher in the winter and lower in the summer. 36 refs., 4 figs., 1 tab.

  7. Structurally distinct polycyclic aromatic hydrocarbons induce differential transcriptional responses in developing zebrafish

    SciTech Connect (OSTI)

    Goodale, Britton C.; Tilton, Susan C.; Corvi, Margaret M.; Wilson, Glenn R.; Janszen, Derek B.; Anderson, Kim A.; Waters, Katrina M.; Tanguay, Robert L.

    2013-11-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment as components of fossil fuels and by-products of combustion. These multi-ring chemicals differentially activate the aryl hydrocarbon receptor (AHR) in a structurally dependent manner, and induce toxicity via both AHR-dependent and -independent mechanisms. PAH exposure is known to induce developmental malformations in zebrafish embryos, and recent studies have shown cardiac toxicity induced by compounds with low AHR affinity. Unraveling the potentially diverse molecular mechanisms of PAH toxicity is essential for understanding the hazard posed by complex PAH mixtures present in the environment. We analyzed transcriptional responses to PAH exposure in zebrafish embryos exposed to benz(a)anthracene (BAA), dibenzothiophene (DBT) and pyrene (PYR) at concentrations that induced developmental malformations by 120 h post-fertilization (hpf). Whole genome microarray analysis of mRNA expression at 24 and 48 hpf identified genes that were differentially regulated over time and in response to the three PAH structures. PAH body burdens were analyzed at both time points using GCMS, and demonstrated differences in PAH uptake into the embryos. This was important for discerning dose-related differences from those that represented unique molecular mechanisms. While BAA misregulated the least number of transcripts, it caused strong induction of cyp1a and other genes known to be downstream of the AHR, which were not induced by the other two PAHs. Analysis of functional roles of misregulated genes and their predicted regulatory transcription factors also distinguished the BAA response from regulatory networks disrupted by DBT and PYR exposure. These results indicate that systems approaches can be used to classify the toxicity of PAHs based on the networks perturbed following exposure, and may provide a path for unraveling the toxicity of complex PAH mixtures. - Highlights: Defined global mRNA expression

  8. Use of SPMDs to determine average water concentration of polycyclic aromatic hydrocarbons in urban stormwater runoff

    SciTech Connect (OSTI)

    DeVita, W.; Crunkilton, R.

    1995-12-31

    Semipermeable polymeric membrane devices (SPMDS) were deployed for 30 day periods to monitor polycyclic aromatic hydrocarbons (PAHs) in an urban stream which receives much of its flow from urban runoff. SPMDs are capable of effectively sampling several liters of water per day for some PAHs. Unlike conventional methods, SPMDs sample only those non-polar organic contaminants which are truly dissolved and available for bioconcentration. Also, SPMDs may concentrate contaminants from episodic events such as stormwater discharge. The State of Wisconsin has established surface water quality criteria based upon human lifetime cancer risk of 23 ppt for benzo(a)pyrene and 23 ppt as the sum of nine other potentially carcinogenic PAHs. Bulk water samples analyzed by conventional methodology were routinely well above this criteria, but contained particulate bound PAHs as well as PAHs bound by dissolved organic carbon (DOC) which are not available for bioconcentration. Average water concentrations of dissolved PAHs determined using SPMDs were also above this criteria. Variables used for determining water concentration included sampling rate at the exposure temperature, length of exposure and estimation of biofouling of SPMD surface.

  9. Polycyclic aromatic hydrocarbons in olive fruits as a measure of air pollution in the valley of Florence (Italy)

    SciTech Connect (OSTI)

    Ignesti, G.; Lodovici, M.; Dolara, P.; Lucia, P.; Grechi, D.

    1992-06-01

    Plants have often been used for monitoring air pollution, such as Tradescantia for detecting mutagenic chemicals, or mosses which are bio-accumulators of heavy metals. Mosses have also been used as indicators of pollution from hexachlorobenzene and polycyclic aromatic hydrocarbons. PAH are present in most crops, and are deposited on the foliar surface of plants exposed to polluted air. Plants grown in heavily polluted environments have a higher concentration of PAH than those growing in clean environments, and plants grown in cabinets with filtered air have a very low concentration of PAH. Alimentary oils have high concentrations of PAH due to crop exposure to air pollutants and a high solubility of PAH in oils. PAH are important initiators of some human cancers and their monitoring is believed to be important for public health. Most Italian towns are heavily polluted by car exhaust and industrial sources, and a high concentration of PAH has been reported in the air particulate of urban areas. On the basis of these premises we thought it of interest to determine the concentration of some PAH in the olive fruits of trees growing in the valley of Florence (Italy), to establish if this approach could be useful for monitoring air pollution by PAH. 9 refs., 3 figs.

  10. In situ toxicity evaluations of turbidity and photoinduction of polycyclic aromatic hydrocarbons

    SciTech Connect (OSTI)

    Ireland, D.S.; Burton, G.A. Jr; Hess, G.G.

    1996-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are prevalent pollutants in the aquatic environment that can cause a wide range of toxic effects. Earlier studies have shown that toxicity of PAHs can be enhanced by ultraviolet (UV) radiation. In situ and laboratory exposures with Ceriodaphnia dubia were used to evaluate photoinduced toxicity of PAHs in wet-weather runoff and in turbid conditions. Exposure to UV increased the toxicity of PAH-contaminated sediment to C. dubia. Toxicity was removed when UV wavelengths did not penetrate the water column to the exposed organisms. A significant correlation was observed between in situ C. dubia survival and turbidity when organisms were exposed to sunlight. Stormwater runoff samples exhibited an increase in chronic toxicity (reproduction) to C. dubia when exposed to UV wavelengths as compared to C. dubia not exposed to UV wavelengths. Toxicity was reduced significantly in the presence of UV radiation when the organic fraction of stormwater runoff was removed. The PAHs are bound to the sediment and resuspended into the water column once the sediment is disturbed (e.g., during a storm). The in situ and laboratory results showed that photoinduced toxicity occurred frequently during low flow conditions and wet weather runoff and was reduced in turbid conditions.

  11. Probabilistic ecological risk assessment and source apportionment of polycyclic aromatic hydrocarbons in surface sediments from Yellow Sea

    SciTech Connect (OSTI)

    Liu, A.X.; Lang, Y.H.; Xue, L.D.; Liao, S.L.; Zhou, H.

    2009-11-15

    Based on the concentrations of polycyclic aromatic hydrocarbons (PAHs) in 12 surface sediment samples from Yellow Sea, the relative risk of 9 PAHs was investigated using joint risk probability distribution curves and overlapping area, which were generated based on the distributions of exposure and acute toxicity data (LC50), and the sources of PAHs were apportioned using principal component analysis. It was found that joint probability curve and overlapping area indicated the acceptable ecological risk of individual PAHs, only a small fraction of the benthic organisms was affected. Among the nine PAHs studied, the overall risk of pyrene was the highest, with that of naphthalene the lowest. For lower exposure levels at which the percentage of species affected was less than 10%, the risk associated with phenanthrene and fluorene were clearly higher than that of the other seven PAHs. It was indicated that PAHs in surface sediments mainly originated from vehicular emissions, coal combustion sources, coke oven emission and wood combustion, petroleum origin made little influence on sources of PAHs by PCA.

  12. Occurrence of polycyclic aromatic hydrocarbons below coal-tar-sealed parking lots and effects on stream benthic macroinvertebrate communities

    SciTech Connect (OSTI)

    Scoggins, M.; McClintock, N.L.; Gosselink, L.; Bryer, P.

    2007-12-15

    Parking-lot pavement sealants recently have been recognized as a major source of polycyclic aromatic hydrocarbons (PAHs) in urban stream sediments in Austin, Texas. Laboratory and field studies have shown that PAHs in sediments can be toxic to aquatic organisms and can degrade aquatic communities. After identifying increases in concentrations of PAHs in sediments below seal-coated parking lots, we investigated whether the increases had significant effects on stream biota in 5 Austin streams. We sampled sediment chemistry and biological communities above and below the point at which stormwater runoff from the parking lots discharged into the streams, thus providing 5 upstream reference sites and 5 downstream treatment sites. Differences between upstream and downstream concentrations of total PAH ranged from 3.9 to 32 mg/kg. Analysis of the species occurrence data from pool and riffle habitats indicated a significant decrease in community health at the downstream sites, including decreases in richness, intolerant taxa, Diptera taxa, and density. In pool sediments, Chironomidae density was negatively correlated with PAH concentrations, whereas Oligochaeta density responded positively to PAH concentrations. In general, pool taxa responded more strongly than riffle taxa to PAHs, but riffle taxa responded more broadly than pool taxa. Increases in PAH sediment-toxicity units between upstream and downstream sites explained decreases in taxon richness and density in pools between upstream and downstream sites.

  13. Air pollution from a large steel factory: polycyclic aromatic hydrocarbon emissions from coke-oven batteries

    SciTech Connect (OSTI)

    Lorenzo Liberti; Michele Notarnicola; Roberto Primerano; Paolo Zannetti

    2006-03-15

    A systematic investigation of solid and gaseous atmospheric emissions from some coke-oven batteries of one of Europe's largest integrated steel factory (Taranto, Italy) has been carried out. These emissions, predominantly diffuse, originate from oven leakages, as well as from cyclic operations of coal loading and coke unloading. In air monitoring samples, polycyclic aromatic hydrocarbons (PAHs) were consistently detected at concentrations largely exceeding threshold limit values. By means of PAHs speciation profile and benzo-(a)pyrene (BaP) equivalent dispersion modeling from diffuse sources, the study indicated that serious health risks exist not only in working areas, but also in a densely populated residential district near the factory. 30 refs., 5 figs., 3 tabs.

  14. Polycyclic aromatic hydrocarbons in surface waters of Alessandria District, South Eastern Piedmont (Italy)

    SciTech Connect (OSTI)

    Trova, C.; Cossa, G.; Gandolfo, G.

    1992-10-01

    Polynuclear aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants. Because of the high toxicity of some polycyclic compounds, such as benzopyrenes, the determination of their levels in air, water, soil and aquatic organisms was the object of several papers. Anthropogenic pyrolitic and combustion processes, related to industrial plants, domestic heating, automobile traffic, are the major sources of these compounds; from these sources they enter atmospheric environment where their concentration is reduced by scavenging during precipitation events: rain, snow and fog in urban areas usually show high contents of PAHs. Dry and wet atmospheric polluted depositions effluents transport appreciable amounts of PAHs to aquatic environment, where they are rapidly taken up and accumulated by both fish and shellfish. Alessandria District, in South-Eastern Piedmont (Italy), lies in the middle of Torino-Milano-Genova industrial area: in addition to local sources, a relatively long range transport of polluted air masses may conduct to this region atmospheric contaminants, such as polynuclear compounds, that can enter fluvial environments through meteoric precipitation. The object of this work was to evaluate PAH content in surface waters flowing across the described territory. Samplings were carried on during winter season, when the concentration of these pollutants usually reaches the highest levels. 8 refs., 4 figs., 2 tabs.

  15. Polycyclic aromatic hydrocarbons at selected burning grounds at Los Alamos National Laboratory

    SciTech Connect (OSTI)

    Harris, B.W.; Minor, L.K.M.; Flucas, B.J.

    1998-02-01

    A commercial immunoassay field test (IFT) was used to rapidly assess the total concentrations of polycyclic aromatic hydrocarbons (PAHs) in the soil at selected burning grounds within the explosives corridor at Los Alamos National Laboratory (LANL). Results were compared with analyses obtained from LANL Analytical Laboratory and from a commercial laboratory. Both used the Environmental Protection Agency`s (EPA`s) Methods 8270 and 8310. EPA`s Method 8270 employs gas chromatography and mass spectral analyses, whereas EPA`s Method 8310 uses an ultraviolet detector in a high-performance liquid chromatography procedure. One crude oil sample and one diesel fuel sample, analyzed by EPA Method 8270, were included for references. On an average the IFT results were lower for standard samples and lower than the analytical laboratory results for the unknown samples. Sites were selected to determine whether the PAHs came from the material burned or the fuel used to ignite the burn, or whether they are produced by a high-temperature chemical reaction during the burn. Even though the crude oil and diesel fuel samples did contain measurable quantities of PAHs, there were no significant concentrations of PAHs detected in the ashes and soil at the burning grounds. Tests were made on fresh soil and ashes collected after a large burn and on aged soil and ashes known to have been at the site more than three years. Also analyzed were twelve-year-old samples from an inactive open burn cage.

  16. Polycyclic aromatic hydrocarbons in fresh and smoked fish samples from three Nigerian cities

    SciTech Connect (OSTI)

    Akpan, V.; Lodovici, M.; Dolara, P. )

    1994-08-01

    Nigeria is a major producer of crude oil in sub-Saharan Africa. In-shore and off-shore wells are located in richly watered creeks in the southern part of the country. Although published data on environmental impact assessment of the petroleum industry in Nigeria are lacking, there is a growing concern about the possible contamination of estuarine and coastal waters and of marine species by polycyclic aromatic hydrocarbon (PAHs). PAHs are ubiquitous priority pollutants that occur naturally in crude oil, automobile exhaust emissions and smoke condensates from incomplete combustion of carbonaceous materials. PAHs with high molecular weight are less readily biodegraded by indigenous microorganisms in some regions, and given their marked hydrophobic characteristics, may persist in the aqueous environment, thus contaminating the food chain by bioaccumulating in aquatic species like fish and mussels. Major Nigerian oil wells are located in the vicinity of breeding and harvesting sites serving the fresh-water fishing industry. Large hauls of fresh fish are normally consumed cooked in soups or smoke cured in handcrafted traditional ovens using freshly cut red mangrove (Rhizophora racemosa) wood as fuel. Though smoke curing is economical and may ensure longer conservation of fish, it undoubtedly increases the burden of PAHs in finished products as a result of partial charring and from smoke condensates or mangroves that also contain PAHs in measurable quantities as reported by Asita et al. (1991). Apart from PAHs analyzed by Emerole (1980) in smoked food samples from Ibadan using simple analytical methods, those from industrial and other anthropogenic sources have rarely been analyzed in Nigeria. We tried therefore to update the data and address this discrepancy. 14 refs., 4 figs., 2 tabs.

  17. Polycyclic aromatic hydrocarbons (PAH) formation from the pyrolysis...

    Office of Scientific and Technical Information (OSTI)

    the pyrolysis of different municipal solid waste fractions Citation Details In-Document ... Resource Relation: Journal Name: Waste Management; Journal Volume: 36; Other ...

  18. First-principles investigation on the electronic efficiency and binding energy of the contacts formed by graphene and poly-aromatic hydrocarbon anchoring groups

    SciTech Connect (OSTI)

    Li, Yang; Tu, Xingchen; Wang, Hao; Hou, Shimin; Sanvito, Stefano

    2015-04-28

    The electronic efficiency and binding energy of contacts formed between graphene electrodes and poly-aromatic hydrocarbon (PAH) anchoring groups have been investigated by the non-equilibrium Greens function formalism combined with density functional theory. Our calculations show that PAH molecules always bind in the interior and at the edge of graphene in the AB stacking manner, and that the binding energy increases following the increase of the number of carbon and hydrogen atoms constituting the PAH molecule. When we move to analyzing the electronic transport properties of molecular junctions with a six-carbon alkyne chain as the central molecule, the electronic efficiency of the graphene-PAH contacts is found to depend on the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the corresponding PAH anchoring group, rather than its size. To be specific, the smaller is the HOMO-LUMO gap of the PAH anchoring group, the higher is the electronic efficiency of the graphene-PAH contact. Although the HOMO-LUMO gap of a PAH molecule depends on its specific configuration, PAH molecules with similar atomic structures show a decreasing trend for their HOMO-LUMO gap as the number of fused benzene rings increases. Therefore, graphene-conjugated molecule-graphene junctions with high-binding and high-conducting graphene-PAH contacts can be realized by choosing appropriate PAH anchor groups with a large area and a small HOMO-LUMO gap.

  19. Distribution of polycyclic aromatic hydrocarbons in fly ash during coal and residual char combustion in a pressurized fluidized bed

    SciTech Connect (OSTI)

    Hongcang Zhou; Baosheng Jin; Rui Xiao; Zhaoping Zhong; Yaji Huang

    2009-04-15

    To investigate the distribution of polycyclic aromatic hydrocarbons (PAHs) in fly ash, the combustion of coal and residual char was performed in a pressurized spouted fluidized bed. After Soxhlet extraction and Kuderna-Danish (K-D) concentration, the contents of 16 PAHs recommended by the United States Environmental Protection Agency (U.S. EPA) in coal, residual char, and fly ash were analyzed by a high-performance liquid chromatography (HPLC) coupled with fluorescence and diode array detection. The experimental results show that the combustion efficiency is lower and the carbon content in fly ash is higher during coal pressurized combustion, compared to the residual char pressurized combustion at the pressure of 0.3 MPa. Under the same pressure, the PAH amounts in fly ash produced from residual char combustion are lower than that in fly ash produced from coal combustion. The total PAHs in fly ash produced from coal and residual char combustion are dominated by three- and four-ring PAHs. The amounts of PAHs in fly ash produced from residual char combustion increase and then decrease with the increase of pressure in a fluidized bed. 21 refs., 1 fig., 4 tabs.

  20. 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

  1. MODELING GALACTIC EXTINCTION WITH DUST AND 'REAL' POLYCYCLIC AROMATIC HYDROCARBONS

    SciTech Connect (OSTI)

    Mulas, Giacomo; Casu, Silvia; Cecchi-Pestellini, Cesare; Zonca, Alberto E-mail: silvia@oa-cagliari.inaf.it E-mail: azonca@oa-cagliari.inaf.it

    2013-07-01

    We investigate the remarkable apparent variety of galactic extinction curves by modeling extinction profiles with core-mantle grains and a collection of single polycyclic aromatic hydrocarbons. Our aim is to translate a synthetic description of dust into physically well-grounded building blocks through the analysis of a statistically relevant sample of different extinction curves. All different flavors of observed extinction curves, ranging from the average galactic extinction curve to virtually 'bumpless' profiles, can be described by the present model. We prove that a mixture of a relatively small number (54 species in 4 charge states each) of polycyclic aromatic hydrocarbons can reproduce the features of the extinction curve in the ultraviolet, dismissing an old objection to the contribution of polycyclic aromatic hydrocarbons to the interstellar extinction curve. Despite the large number of free parameters (at most the 54 Multiplication-Sign 4 column densities of each species in each ionization state included in the molecular ensemble plus the 9 parameters defining the physical properties of classical particles), we can strongly constrain some physically relevant properties such as the total number of C atoms in all species and the mean charge of the mixture. Such properties are found to be largely independent of the adopted dust model whose variation provides effects that are orthogonal to those brought about by the molecular component. Finally, the fitting procedure, together with some physical sense, suggests (but does not require) the presence of an additional component of chemically different very small carbonaceous grains.

  2. Polycyclic aromatic hydrocarbon and mid-infrared continuum emission in a z > 4 submillimeter galaxy

    SciTech Connect (OSTI)

    Riechers, Dominik A.; Pope, Alexandra; Daddi, Emanuele; Elbaz, David; Carilli, Christopher L.; Walter, Fabian; Hodge, Jacqueline; Morrison, Glenn E.; Dickinson, Mark; Dannerbauer, Helmut

    2014-05-01

    We report the detection of 6.2 μm polycyclic aromatic hydrocarbon (PAH) and rest-frame 4-7 μm continuum emission in the z = 4.055 submillimeter galaxy GN20, using the Infrared Spectrograph on board the Spitzer Space Telescope. This represents the first detection of PAH emission at z > 4. The strength of the PAH emission feature is consistent with a very high star formation rate of ∼1600 M {sub ☉} yr{sup –1}. We find that this intense starburst powers at least ∼1/3 of the faint underlying 6 μm continuum emission, with an additional, significant (and perhaps dominant) contribution due to a power-law-like hot dust source, which we interpret to likely be a faint, dust-obscured active galactic nucleus (AGN). The inferred 6 μm AGN continuum luminosity is consistent with a sensitive upper limit on the hard X-ray emission as measured by the Chandra X-Ray Observatory if the previously undetected AGN is Compton-thick. This is in agreement with the finding at optical/infrared wavelengths that the galaxy and its nucleus are heavily dust-obscured. Despite the strong power-law component enhancing the mid-infrared continuum emission, the intense starburst associated with the photon-dominated regions that give rise to the PAH emission appears to dominate the total energy output in the infrared. GN20 is one of the most luminous starburst galaxies known at any redshift, embedded in a rich protocluster of star-forming galaxies. This investigation provides an improved understanding of the energy sources that power such exceptional systems, which represent the extreme end of massive galaxy formation at early cosmic times.

  3. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene

    SciTech Connect (OSTI)

    Mackie, Cameron J. Candian, Alessandra; Tielens, Alexander G. G. M.; Huang, Xinchuan; Maltseva, Elena; Buma, Wybren Jan; Petrignani, Annemieke; Oomens, Jos; Lee, Timothy J.

    2015-12-14

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C–H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned.

  4. Field application of a genetically engineered microorganism for polycyclic aromatic hydrocarbon bioremediation process monitoring and control

    SciTech Connect (OSTI)

    Sayler, G.S.; Cox, C.D.; Ripp, S.; Nivens, D.E.; Werner, C.; Ahn, Y.; Matrubutham, U.; Burlage, R.

    1998-11-01

    On October 30, 1996, the US Environmental Protection Agency (EPA) commenced the first test release of genetically engineered microorganisms (GEMs) for use in bioremediation. The specific objectives of the investigation were multifaceted and include (1) testing the hypothesis that a GEM can be successfully introduced and maintained in a bioremediation process, (2) testing the concept of using, at the field scale, reporter organisms for direct bioremediation process monitoring and control, and (3) acquiring data that can be used in risk assessment decision making and protocol development for future field release applications of GEMs. The genetically engineered strain under investigation is Pseudomonas fluorescens strain HK44 (King et al., 1990). The original P. fluorescens parent strain was isolated from polycyclic aromatic hydrocarbon (PAH) contaminated manufactured gas plant soil. Thus, this bacterium is able to biodegrade naphthalene (as well as other substituted naphthalenes and other PAHs) and is able to function as a living bioluminescent reporter for the presence of naphthalene contamination, its bioavailability, and the functional process of biodegradation. A unique component of this field investigation was the availability of an array of large subsurface soil lysimeters. This article describes the experience associated with the release of a genetically modified microorganism, the lysimeter facility and its associated instrumentation, as well as representative data collected during the first eighteen months of operation.

  5. Estimating the aqueous solubility of aromatic hydrocarbons by high performance liquid chromatography

    SciTech Connect (OSTI)

    Whitehouse, B.G.; Cooke, R.C.

    1982-01-01

    Empirical equations which correlate high performance liquid chromatography capacity factor (k') to aromatic hydrocarbon aqueous solubility are developed. The correlations of k' to octanol-water partition coefficients, and k' to hydrocarbon surface area are also shown.

  6. Cardiac toxicity of 5-ring polycyclic aromatic hydrocarbons is differentially dependent on the aryl hydrocarbon receptor 2 isoform during zebrafish development

    SciTech Connect (OSTI)

    Incardona, John P. Linbo, Tiffany L.; Scholz, Nathaniel L.

    2011-12-15

    Petroleum-derived compounds, including polycyclic aromatic hydrocarbons (PAHs), commonly occur as complex mixtures in the environment. Recent studies using the zebrafish experimental model have shown that PAHs are toxic to the embryonic cardiovascular system, and that the severity and nature of this developmental cardiotoxicity varies by individual PAH. In the present study we characterize the toxicity of the relatively higher molecular weight 5-ring PAHs benzo[a]pyrene (BaP), benzo[e]pyrene (BeP), and benzo[k]fluoranthene (BkF). While all three compounds target the cardiovascular system, the underlying role of the ligand-activated aryl hydrocarbon receptor (AHR2) and the tissue-specific induction of the cytochrome p450 metabolic pathway (CYP1A) were distinct for each. BaP exposure (40 {mu}M) produced AHR2-dependent bradycardia, pericardial edema, and myocardial CYP1A immunofluorescence. By contrast, BkF exposure (4-40 {mu}M) caused more severe pericardial edema, looping defects, and erythrocyte regurgitation through the atrioventricular valve that were AHR2-independent (i.e., absent myocardial or endocardial CYP1A induction). Lastly, exposure to BeP (40 {mu}M) yielded a low level of CYP1A+ signal in the vascular endothelium of the head and trunk, without evident toxic effects on cardiac function or morphogenesis. Combined with earlier work on 3- and 4-ring PAHs, our findings provide a more complete picture of how individual PAHs may drive the cardiotoxicity of mixtures in which they predominate. This will improve toxic injury assessments and risk assessments for wild fish populations that spawn in habitats altered by overlapping petroleum-related human impacts such as oil spills, urban stormwater runoff, or sediments contaminated by legacy industrial activities. -- Highlights: Black-Right-Pointing-Pointer PAH compounds with 5 rings in different arrangements caused differential tissue-specific patterns of CYP1A induction in zebrafish embryos. Black

  7. THE CONNECTION BETWEEN 3.3 {mu}m POLYCYCLIC AROMATIC HYDROCARBON EMISSION AND ACTIVE GALACTIC NUCLEUS ACTIVITY

    SciTech Connect (OSTI)

    Woo, Jong-Hak; Park, Dawoo; Kim, Ji Hoon; Imanishi, Masatoshi

    2012-02-15

    We investigate the connection between starburst and active galactic nucleus (AGN) activity by comparing 3.3 {mu}m polycyclic aromatic hydrocarbon (PAH) emission with AGN properties. Utilizing the slitless spectroscopic capability of the AKARI space telescope, we observe a moderate-luminosity Type I AGN at z {approx} 0.4 to measure global starburst activity. The 3.3 {mu}m PAH emissions are detected for 7 out of 26 target galaxies. We find no strong correlation between the 3.3 {mu}m PAH emission and AGN luminosity in the limited range of the observed AGN luminosity, suggesting that global star formation may not be closely related to AGN activity. Combining our measurements with previous 3.3 {mu}m measurements of low-redshift Type I AGNs in the literature, we investigate the connection between nuclear starburst and AGN activity. In contrast to global star formation, the 3.3 {mu}m PAH luminosity measured from the central part of galaxies correlates with AGN luminosity, implying that starburst activity and AGN activity are directly connected in the nuclear region.

  8. ON THE VIABILITY OF THE PAH MODEL AS AN EXPLANATION OF THE UNIDENTIFIED INFRARED EMISSION FEATURES

    SciTech Connect (OSTI)

    Zhang, Yong; Kwok, Sun E-mail: sunkwok@hku.hk

    2015-01-01

    Polycyclic aromatic hydrocarbon (PAH) molecules are widely considered the preferred candidate for the carrier of the unidentified infrared emission bands observed in the interstellar medium and circumstellar envelopes. In this paper, we report the results of fitting a variety of non-PAH spectra (silicates, hydrogenated amorphous carbon, coal, and even artificial spectra) using the theoretical infrared spectra of PAHs from the NASA Ames PAH IR Spectroscopic Database. We show that these non-PAH spectra can be well fitted by PAH mixtures. This suggests that a general match between astronomical spectra and those of PAH mixtures does not necessarily provide definitive support for the PAH hypothesis.

  9. UV resonance Raman characterization of polycyclic aromatic hydrocarbons in coal liquid distillates

    SciTech Connect (OSTI)

    Rumelfanger, R.; Asher, S.A.; Perry, M.B.

    1988-02-01

    Ultraviolet resonance Raman spectroscopy has been used to characterize the polycyclic aromatic hydrocarbon composition of a series of distillates of coal-derived liquids. The UV Raman spectra easily monitor changes in the polycyclic aromatic hydrocarbon composition as a function of distillation temperature. Specific species, such as pyrene, can be determined by judicious choice of excitation wavelength.

  10. Synthesis of condensed phases containing polycyclic aromatic hydrocarbons fullerenes and nanotubes

    DOE Patents [OSTI]

    Reilly, Peter T. A.

    2004-10-19

    The invention relates to methods for producing polycyclic aromatic hydrocarbons, fullerenes, and nanotubes, comprising: a. heating at least one carbon-containing material to form a condensed phase comprising at least one polycyclic aromatic hydrocarbon; b. collecting at least some of the condensed phase; c. reacting the condensed phase to form fullerenes and/or nanotubes.

  11. A 700 year sediment record of black carbon and polycyclic aromatic hydrocarbons near the EMEP air monitoring station in Aspvreten, Sweden

    SciTech Connect (OSTI)

    Marie Elmquist; Zdenek Zencak; Oerjan Gustafsson

    2007-10-15

    In view of poor constraints on historical combustion emissions, past environmental loadings of black carbon (BC) and polycyclic aromatic hydrocarbon (PAH) were reconstructed from dated lake sediment cores collected 70 km south of Stockholm, Sweden. Compared to several dramatic variations over the recent 150 years, the preindustrial loadings were steady within {+-}50% through the entire medieval with BC fluxes of 0.071 g m{sup -2} yr{sup -1} and PAH fluxes of 6 g m{sup -2} yr{sup -1}. In the wood-burning dominated century leading up to the industrial revolution around 1850, increasing BC fluxes were leading PAH fluxes. BC fluxes reached their millennial-scale maximum around 1920, whereas PAH fluxes increased exponentially to its record maximum around 1960, 50-fold above preindustrial values. For 1920-1950, BC fluxes consistently decreased as PAH fluxes kept increasing. Coal and coke represented >50% of the Swedish energy market in the 1930s. Combined with sharply decreasing (1,7-)/(1,7{+-}2,6-dimethylphenanthrene), indicative of diminishing wood combustion, and decreasing methylphenanthrenes/phenanthrene, indicative of higher-temperature combustion (coal instead of wood), the sediment archive suggests that the relative BC/PAH emission factors thus are lower for coal than for wood combustion. For the first time, both BC and PAH fluxes decreased after 1960. This trend break is a testament to the positive effects of decreasing reliance on petroleum fuels and a number of legislative actions aimed at curbing emissions and by 1990, the loading of BC was back at preindustrial levels, whereas that of PAH were the lowest since the 1910s. However, for the most recent period (1990-2004) the BC and PAH fluxes are no longer decreasing. 55 refs., 3 figs.

  12. Source Contribution Analysis of Surface Particulate Polycyclic Aromatic Hydrocarbon Concentrations in Northeastern Asia by Source-receptor Relationships

    SciTech Connect (OSTI)

    Inomata, Yayoi; Kajino, Mizuo; Sato, Keiichi; Ohara, Toshimasa; Kurokawa, Jun-Ichi; Ueda, Hiromasa; Tang, Ning; Hayakawa, Kazuichi; Ohizumi, Tsuyoshi; Akimoto, Hajime

    2013-11-01

    We analyzed the sourceereceptor relationships for particulate polycyclic aromatic hydrocarbon (PAH) concentrations in northeastern Asia using an aerosol chemical transport model. The model successfully simulated the observed concentrations. In Beijing (China) benzo[a]pyren (BaP) concentrations are due to emissions from its own domain. In Noto, Oki and Tsushima (Japan), transboundary transport from northern China (>40N, 40-60%) and central China (30-40N, 10-40%) largely influences BaP concentrations from winter to spring, whereas the relative contribution from central China is dominant (90%) in Hedo. In the summer, the contribution from Japanese domestic sources increases (40-80%) at the 4 sites. Contributions from Japan and Russia are additional source of BaP over the northwestern Pacific Ocean in summer. The contribution rates for the concentrations from each domain are different among PAH species depending on their particulate phase oxidation rates. Reaction with O3 on particulate surfaces may be an important component of the PAH oxidation processes.

  13. Separation, characterization and instrumental analysis of polynuclear aromatic hydrocarbon ring classes in petroleum

    SciTech Connect (OSTI)

    Chmielowiec, J.; Beshai, J.E.; George, A.E.

    1980-08-01

    To develop effective utilization technology for heavy streams from conventional fuels and unconventional resources such as heavy oils and oilsand bitumens, detailed information on the chemical composition of the feedstocks is needed. Attempts were made during the seventies to modify the API Project 60 scheme of analysis or to develop chemically more efficient, and less time-consuming, separation and characterization methods. These attempts aimed to improve characterization by separating the samples into concentrates of different structural types. Samples throughput was increased by using pressure and higher performance chromatographic systems. Other valuable contributions, such as coal-liquid characterization in terms of different chemical functionalities have also been made. The separation of aromatic ring classes and characterization or identification of their major components was our primary objective in this study. A silica-R(NH/sub 2/)/sub 2/-based HPLC system was used in our laboratory to study the analytical potential of this approach; the work was described in a previous publication. In the present study, the applicability of HPLC separation by this system and instrumental spectrometric characterization of 3- and 4-ring PAHs isolated from two Canadian oils were investigated. The oils used, Medicine River and Lloydminster, are examples of hydrocarbon-dominated materials representing light and heavy processing feedstocks, respectively.

  14. Evaluation of a photoelectric aerosol sensor for real-time PAH monitoring. Project report

    SciTech Connect (OSTI)

    Ramamurthi, M.; Chuang, J.C.

    1997-04-01

    In this study, the performance of a Gossen, GmbH Model PAS 1000i Photoelectric Aerosol Sensors (PAS) was evaluated for monitoring the levels of polycyclic aromatic hydrocarbons (PAH) on airborne find particles. The response of the PAS to PAH vapors and to airborne particles of various sizes were determined. Estimated levels of PAH provided by the PAS were compared to the concentrations of PAH sampled and measured traditionally.

  15. Method of upgrading oils containing hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline

    DOE Patents [OSTI]

    Baker, E.G.; Elliott, D.C.

    1993-01-19

    The present invention is a multi-stepped method of converting an oil which is produced by various biomass and coal conversion processes and contains primarily single and multiple ring hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline. The single and multiple ring hydroxyaromatic hydrocarbon compounds in a raw oil material are first deoxygenated to produce a deoxygenated oil material containing single and multiple ring aromatic compounds. Then, water is removed from the deoxygenated oil material. The next step is distillation to remove the single ring aromatic compounds as gasoline. In the third step, the multiple ring aromatics remaining in the deoxygenated oil material are cracked in the presence of hydrogen to produce a cracked oil material containing single ring aromatic compounds. Finally, the cracked oil material is then distilled to remove the single ring aromatics as gasoline.

  16. Method of upgrading oils containing hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline

    DOE Patents [OSTI]

    Baker, Eddie G. (Richland, WA); Elliott, Douglas C. (Richland, WA)

    1993-01-01

    The present invention is a multi-stepped method of converting an oil which is produced by various biomass and coal conversion processes and contains primarily single and multiple ring hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline. The single and multiple ring hydroxyaromatic hydrocarbon compounds in a raw oil material are first deoxygenated to produce a deoxygenated oil material containing single and multiple ring aromatic compounds. Then, water is removed from the deoxygenated oil material. The next step is distillation to remove the single ring aromatic compouns as gasoline. In the third step, the multiple ring aromatics remaining in the deoxygenated oil material are cracked in the presence of hydrogen to produce a cracked oil material containing single ring aromatic compounds. Finally, the cracked oil material is then distilled to remove the single ring aromatics as gasoline.

  17. Refractometric determination of content of aromatic hydrocarbons in AI-93 gasolines

    SciTech Connect (OSTI)

    Kuznetsova, L.M.; Ioffe, B.V.; Mikheeva, E.G.

    1982-11-01

    Investigates the possibility of extending the use of the dispersometric method to the control of aromatic hydrocarbon content in AI-93 gasolines. Uses 4 model blends with aromatics content of 20-40% by weight. Finds that the dispersometric method can be used in analyzing both unleaded and leaded AI-93 gasolines, since the addition of ethyl fluid and dye in formulating the leaded gasolines does not affect the accuracy in determining the aromatic hydrocarbon content. Concludes that the dispersometric method can be used to determine the aromatic hydrocarbon content in AI-93 gasolines to within + or - 1.0% by weight, both in the laboratory (IRF-23M refractometer) and under commercial conditions (in ''Nafta-74'' unit).

  18. Polycyclic aromatic hydrocarbon and mid-infrared continuum emission...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Polycyclic ... We report the detection of 6.2 m polycyclic aromatic ... OSTI Identifier: 22357024 Resource Type: Journal Article ...

  19. Dispersion modeling of polycyclic aromatic hydrocarbons from combustion of biomass and fossil fuels and production of coke in Tianjin, China

    SciTech Connect (OSTI)

    Shu Tao; Xinrong Li; Yu Yang; Raymond M. Coveney, Jr.; Xiaoxia Lu; Haitao Chen; Weiran Shen

    2006-08-01

    A USEPA procedure, ISCLT3 (Industrial Source Complex Long-Term), was applied to model the spatial distribution of polycyclic aromatic hydrocarbons (PAHs) emitted from various sources including coal, petroleum, natural gas, and biomass into the atmosphere of Tianjin, China. Benzo(a)pyrene equivalent concentrations (BaPeq) were calculated for risk assessment. Model results were provisionally validated for concentrations and profiles based on the observed data at two monitoring stations. The dominant emission sources in the area were domestic coal combustion, coke production, and biomass burning. Mainly because of the difference in the emission heights, the contributions of various sources to the average concentrations at receptors differ from proportions emitted. The shares of domestic coal increased from {approximately} 43% at the sources to 56% at the receptors, while the contributions of coking industry decreased from {approximately} 23% at the sources to 7% at the receptors. The spatial distributions of gaseous and particulate PAHs were similar, with higher concentrations occurring within urban districts because of domestic coal combustion. With relatively smaller contributions, the other minor sources had limited influences on the overall spatial distribution. The calculated average BaPeq value in air was 2.54 {+-} 2.87 ng/m{sup 3} on an annual basis. Although only 2.3% of the area in Tianjin exceeded the national standard of 10 ng/m{sup 3}, 41% of the entire population lives within this area. 37 refs., 9 figs.

  20. Polycyclic aromatic hydrocarbon-induced CYP1B1 activity is suppressed by perillyl alcohol in MCF-7 cells

    SciTech Connect (OSTI)

    Chan, Nelson L.S.; Wang Huan; Wang Yun; Leung, H.Y.; Leung, Lai K. . E-mail: laikleung@yahoo.com

    2006-06-01

    Perillyl alcohol (POH) is a dietary monoterpene with potential applications in chemoprevention and chemotherapy. Although clinical trials are under way, POH's physiological and pharmacological properties are still unclear. In the present study, the effect of POH on polycyclic aromatic hydrocarbon (PAH)-induced genotoxicity, and the related expression were examined in MCF-7 cells. Exposure to environmental toxicant increases the risk of cancer. Many of these compounds are pro-carcinogens and are biotransformed into their ultimate genotoxic structures by xenobiotic metabolizing enzymes. CYP1A1 and 1B1 are enzymes that catalyze the biotransformation of dimethylbenz[a]anthracene (DMBA). Our data revealed that 0.5 {mu}M of POH was effective in blocking DMBA-DNA binding. Ethoxyresorufin-O-deethylase (EROD) assay indicated that the administration of POH inhibited the DMBA-induced enzyme activity in MCF-7 cells. Enzyme kinetic analysis revealed that POH inhibited CYP1B1 but not CYP1A1 activity. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) assay also demonstrated that the monoterpene reduced CYP1B1 mRNA abundance induced by DMBA. The present study illustrated that POH might inhibit and downregulate CYP1B1, which could protect against PAH-induced carcinogenesis.

  1. Distribution of Polycyclic Aromatic Hydrocarbons in Soils and Terrestrial Biota After a Spill of Crude Oil in Trecate, Italy

    SciTech Connect (OSTI)

    Brandt, Charles A. ); Becker, James M. ); Porta, Augusto C.

    2001-12-01

    Following a large blowout of crude oil in northern Italy in 1994, the distribution of polyaromatic hydrocarbons (PAHs) was examined over time and space in soils, uncultivated wild vegetation, insects, mice, and frogs in the area. Within 2 y of the blowout, PAH concentrations declined to background levels over much of the area where initial concentrations were within an order of magnitude above background, but had not declined to background in areas where starting concentrations exceeded background by two orders of magnitude. Octanol-water partitioning and extent of alkylation explained much of the variance in uptake of PAHs by plants and animals. Lower Kow PAHs and higher-alkylated PAHs had higher soil-to-biota accumulation factors (BSAFs) than did high-Kow and unalkylated forms. BSAFs for higher Kow PAHs were very low for plants, but much higher for animals, with frogs accumulating more of these compounds than other species.

  2. Application of a fuzzy neural network model in predicting polycyclic aromatic hydrocarbon-mediated perturbations of the Cyp1b1 transcriptional regulatory network in mouse skin

    SciTech Connect (OSTI)

    Larkin, Andrew; Siddens, Lisbeth K.; Krueger, Sharon K.; Tilton, Susan C.; Waters, Katrina M.; Williams, David E.; Baird, William M.

    2013-03-01

    Polycyclic aromatic hydrocarbons (PAHs) are present in the environment as complex mixtures with components that have diverse carcinogenic potencies and mostly unknown interactive effects. Non-additive PAH interactions have been observed in regulation of cytochrome P450 (CYP) gene expression in the CYP1 family. To better understand and predict biological effects of complex mixtures, such as environmental PAHs, an 11 gene input-1 gene output fuzzy neural network (FNN) was developed for predicting PAH-mediated perturbations of dermal Cyp1b1 transcription in mice. Input values were generalized using fuzzy logic into low, medium, and high fuzzy subsets, and sorted using k-means clustering to create Mamdani logic functions for predicting Cyp1b1 mRNA expression. Model testing was performed with data from microarray analysis of skin samples from FVB/N mice treated with toluene (vehicle control), dibenzo[def,p]chrysene (DBC), benzo[a]pyrene (BaP), or 1 of 3 combinations of diesel particulate extract (DPE), coal tar extract (CTE) and cigarette smoke condensate (CSC) using leave-one-out cross-validation. Predictions were within 1 log{sub 2} fold change unit of microarray data, with the exception of the DBC treatment group, where the unexpected down-regulation of Cyp1b1 expression was predicted but did not reach statistical significance on the microarrays. Adding CTE to DPE was predicted to increase Cyp1b1 expression, whereas adding CSC to CTE and DPE was predicted to have no effect, in agreement with microarray results. The aryl hydrocarbon receptor repressor (Ahrr) was determined to be the most significant input variable for model predictions using back-propagation and normalization of FNN weights. - Highlights: ? Tested a model to predict PAH mixture-mediated changes in Cyp1b1 expression ? Quantitative predictions in agreement with microarrays for Cyp1b1 induction ? Unexpected difference in expression between DBC and other treatments predicted ? Model predictions for

  3. SPITZER DETECTION OF POLYCYCLIC AROMATIC HYDROCARBONS AND SILICATE FEATURES IN POST-AGB STARS AND YOUNG PLANETARY NEBULAE

    SciTech Connect (OSTI)

    Cerrigone, Luciano; Hora, Joseph L.; Umana, Grazia; Trigilio, Corrado

    2009-09-20

    We have observed a small sample of hot post-asymptotic giant branch (AGB) stars with the Infrared Array Camera (IRAC) and the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope. The stars were selected from the literature on the basis of their far-infrared (IR) excess (i.e., post-AGB candidates) and B spectral type (i.e., close to the ionization of the envelope). The combination of our IRAC observations with Two Micron All Sky Survey and IRAS catalog data, along with previous radio observations in the cm range (where available) allowed us to model the spectral energy distributions of our targets and find that in almost all of them at least two shells of dust at different temperatures must be present, the hot dust component ranging up to 10{sup 3} K. In several targets, grains larger than 1 {mu}m are needed to match the far-IR data points. In particular, in IRAS 17423-1755 grains up to 100 {mu}m must be introduced to match the emission in the millimeter range. We obtained IRS spectra to identify the chemistry of the envelopes and found that more than one-third of the sources in our sample have mixed chemistry, showing both mid-IR bands attributed to polycyclic aromatic hydrocarbons (PAHs) and silicate features. The analysis of the PAH features indicates that these molecules are located in the outflows, far away from the central stars. We consider the larger than expected percentage of mixed-chemistry targets as a selection bias toward stars with a disk or torus around them. Our results strengthen the current picture of mixed chemistry being due to the spatial segregation of different dust populations in the envelopes.

  4. Subtask 1.20 - Development of Methods to Determine the Environmental Availability of PAHs, PCBs, and Petroleum Hydrocarbons

    SciTech Connect (OSTI)

    Steven Hawthorne

    2007-06-30

    Three methods to determine the bioavailability of polycyclic aromatic hydrocarbons were modified and developed for application to polychlorinated biphenyls (PCBs). Water/XAD desorption and selective supercritical fluid extraction methods were developed to determine the rapidly-released fraction of PCBs from contaminated soils and sediments. A method to determine PCBs in sediment pore water based on solid-phase microextraction was also developed that is capable of determining low pg/mL concentrations with water samples as small as 1.5 mL.

  5. Combined application of normal and reversed-phase high-performance liquid chromatography to determining the group composition of aromatic hydrocarbons in petroleum products

    SciTech Connect (OSTI)

    Belous, E.F.; Lanin, S.N.; Nikitin, Yu.S.

    1995-01-01

    The quality and working characteristics of motor fuels essentially depend on the concentration of aromatic hydrocarbons (AHs). Therefore, the development of procedures for the group determination of aromatic hydrocarbons is an important and topical problem in the processing and quality control of petroleum products. The aim of this work was to improve the group separation and quantitative determination of monocyclic and bicyclic aromatic hydrocarbons (MAH and BAH) in light-end products.

  6. Probabilistic ecological risk assessment of selected PAH`s in sediments near a petroleum refinery

    SciTech Connect (OSTI)

    Arnold, W.R.; Biddinger, G.R.

    1995-12-31

    Sediment samples were collected and analyzed for a number of polynuclear aromatic hydrocarbons (PAHs) along a gradient from a petroleum refinery`s wastewater diffuser. These data were used to calculate the potential risk to aquatic organisms using probabilistic modeling and Monte Carlo sampling procedures. Sediment chemistry data were used in conjunction with estimates of Biota-Sediment Accumulation Factors and Non-Polar Narcosis Theory to predict potential risk to bivalves. Bivalves were the receptors of choice because of their lack of a well-developed enzymatic system for metabolizing PAHs. Thus, they represent a species of higher inherent risk of adverse impact. PAHs considered in this paper span a broad range of octanol-water partition coefficients. Results indicate negligible risk of narcotic effects from PAHs existing near the refinery wastewater discharge.

  7. Comparative Developmental Toxicity of Environmentally Relevant Oxygenated PAHs

    SciTech Connect (OSTI)

    Knecht, Andrea; Goodale, Britton; Truong, Lisa; Simonich, Michael; Swanson, Annika; Matzke, Melissa M.; Anderson, Kim A.; Waters, Katrina M.; Tanguay, Robert

    2013-09-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in urban air, dust and in the soil of most industrial coal gassification, coal burning, coke production and wood preservation sites (Howsam and Jones 1998). It is widely recognized that PAHs pose risks to human health,having been associated with increased risks of systemic inflammation (Delfino et al. 2010), cardiopulmonary mortality (Lee et al. 2011; Lewtas 2007) and lung cancer mortality (Grant 2009; Hoshuyama et al. 2006). The potential risks may be especially acute for the developing fetus and infant where PAH exposures have been linked to low birth weight, intrauterine growth retardation, in-utero mortality and lower intelligence (Dejmek et al. 1999; Dejmek et al. 2000; Perera et al. 1999; Perera et al. 2009; Perera et al. 2006; Perera et al. 1998; Wu et al. 2010). Despite the more than two decades of intensive study devoted to parent PAHs, they are only part of the hazard spectrum from PAH contamination.

  8. Polycyclic aromatic hydrocarbon-DNA adducts and the CYP1A1 restriction fragment length polymorphism

    SciTech Connect (OSTI)

    Shields, P.G.; Bowman, E.D.; Weston, A.; Harris, C.C.; Sugimura, H.; Caporaso, N.E.; Petruzzelli, S.F. ); Trump, B.F. )

    1992-11-01

    Human cancer risk assessment at a genetic level involves the investigation of carcinogen metabolism and DNA adduct formation. Wide interindividual differences in metabolism result in different DNA adduct levels. For this and other reasons, many laboratories have considered DNA adducts to be a measure of the biologically effective dose of a carcinogen. Techniques for studying DNA adducts using chemically specific assays are becoming available. A modification of the [sup 32]P-postlabeling assay for polycyclic aromatic hydrocarbon DNA adducts described here provides potential improvements in quantification. DNA adducts, however, reflect only recent exposure to carcinogens; in contrast, genetic testing for metabolic capacity indicates the extent to which carcinogens can be activated and exert genotoxic effects. Such studies may reflect both separate and integrated risk factors together with DNA adduct levels. A recently described restriction fragment length polymorphism for the CYP1A1, which codes for the cytochrome P450 enzyme primarily responsible for the metabolic activation of carcinogenic polycyclic aromatic hydrocarbons, has been found to be associated with lung cancer risk in a Japanese population. In a subset of individuals enrolled in a US lung cancer case-control study, no association with lung cancer was found. 17 refs., 3 figs.

  9. Polycyclic aromatic hydrocarbon emission profiles and removal efficiency by electrostatic precipitator and wetfine scrubber in an iron ore sintering plant

    SciTech Connect (OSTI)

    Ettore Guerriero; Antonina Lutri; Rosanna Mabilia; Maria Concetta Tomasi Sciano; Mauro Rotatori

    2008-11-15

    A monitoring campaign of polychlorinated dibenzo-p-dioxins and dibenzofurans, polyaromatic hydrocarbons (PAHs), and polychlorinated biphenyl was carried out in an Italian iron ore sintering plant by sampling the combustion gases at the electrostatic precipitator (ESP) outlet, at the Wetfine scrubber (WS) outlet, and by collecting the ESP dust. Few data are available on these micropollutants produced in iron ore sintering plants, particularly from Italian plants. This study investigates the PAH emission profiles and the removal efficiency of ESPs and WS. PAHs were determined at the stack, ESP outlet flue gases, and in ESP dust to characterize the emission profiles and the performance of the ESP and the WS for reducing PAH emission. The 11 PAHs monitored are listed in the Italian legislative decree 152/2006. The mean total PAH sum concentration in the stack flue gases is 3.96 {mu}g/N m{sup 3}, in ESP outlet flue gases is 9.73 {mu}g/N m{sup 3}, and in ESP dust is 0.53 {mu}g/g. Regarding the emission profiles, the most abundant compound is benzo(b)fluoranthene, which has a relative low BaP toxic equivalency factors (TEF) value, followed by dibenzo(a,l)pyrene, which has a very high BaP(TEF) value. The emission profiles in ESP dust and in the flue gases after the ESP show some changes, whereas the fingerprint in ESP and stack flue gases is very similar. The removal efficiency of the ESP and of WS on the total PAH concentration is 5.2 and 59.5%, respectively. 2 figs., 5 tabs.

  10. Catalytic cracking of aromatic hydrocarbons. Final report, October 1984-March 1986

    SciTech Connect (OSTI)

    Simons, G.A.; Ham, D.O.; Moniz, G.A.

    1986-04-01

    Iron containing minerals and chars were screened as cracking catalysts for aromatic hydrocarbons (AHC) in simulated gasifier effluents. Catalytic activities of six minerals and two chars were measured and used to infer fundamental hetereogeneous rate constants using measured properties of the pore structure of the solids. Measurements were made for 200 ppM and 2000 ppM benzene cracking over the temperature range 400 to 1000/sup 0/C. The active catalyst under gasifier conditions was found to be FeO. The minerals have a higher reactivity per unit mass in chars than in a pure form. H/sub 2/S was found to reduce the catalytic activity to one third of the unpoisoned value, but the catalysts maintained this reduced activity. These minerals have the potential to be economically feasible, disposable catalysts in a fixed bed or fluidized bed process if they can survive for ten hours. 8 refs., 33 figs., 3 tabs.

  11. Grating light reflection spectroelectrochemistry for detection of trace amounts of aromatic hydrocarbons in water

    SciTech Connect (OSTI)

    KELLY,MICHAEL J.; SWEATT,WILLIAM C.; KEMME,SHANALYN A.; KASUNIC,K.J.; BLAIR,DIANNA S.; ZAIDI,S.H.; MCNEIL,J.R.; BURGESS,L.W.; BRODSKY,A.M.; SMITH,S.A.

    2000-04-01

    Grating light reflection spectroscopy (GLRS) is an emerging technique for spectroscopic analysis and sensing. A transmission diffraction grating is placed in contact with the sample to be analyzed, and an incident light beam is directed onto the grating. At certain angles of incidence, some of the diffracted orders are transformed from traveling waves to evanescent waves. This occurs at a specific wavelength that is a function of the grating period and the complex index of refraction of the sample. The intensities of diffracted orders are also dependent on the sample's complex index of refraction. The authors describe the use of GLRS, in combination with electrochemical modulation of the grating, for the detection of trace amounts of aromatic hydrocarbons. The diffraction grating consisted of chromium lines on a fused silica substrate. The depth of the grating lines was 1 {micro}m, the grating period was 1 {micro}m, and the duty cycle was 50%. Since chromium was not suitable for electrochemical modulation of the analyte concentration, a 200 nm gold layer was deposited over the entire grating. This gold layer slightly degraded the transmission of the grating, but provided satisfactory optical transparency for the spectroelectrochemical experiments. The grating was configured as the working electrode in an electrochemical cell containing water plus trace amounts of the aromatic hydrocarbon analytes. The grating was then electrochemically modulated via cyclic voltammetry waveforms, and the normalized intensity of the zero order reflection was simultaneously measured. The authors discuss the lower limits of detection (LLD) for two analytes, 7-dimethylamino-1,2-benzophenoxazine (Meldola's Blue dye) and 2,4,6-trinitrotoluene (TNT), probed with an incident HeNe laser beam ({lambda} = 543.5 nm) at an incident angle of 52.5{degree}. The LLD for 7-dimethylamino-1,2-benzophenoxazine is approximately 50 parts per billion (ppb), while the LLD for TNT is approximately 50 parts

  12. Gas-phase reactions of polycyclic aromatic hydrocarbon cations and their nitrogen-containing analogs with H atoms

    SciTech Connect (OSTI)

    Demarais, Nicholas J.; Yang, Zhibo; Bierbaum, Veronica M. [Department of Chemistry and Biochemistry, 215 UCB, University of Colorado, Boulder, CO 80309-0215 (United States); Snow, Theodore P., E-mail: Nicholas.Demarais@Colorado.edu, E-mail: Zhibo.Yang@ou.edu, E-mail: Veronica.Bierbaum@Colorado.edu, E-mail: Theodore.Snow@Colorado.edu [Center for Astrophysics and Space Astronomy, 389 UCB, University of Colorado, Boulder, CO 80309-0389 (United States)

    2014-03-20

    We have studied the reactions of polycyclic aromatic hydrocarbon cations and their nitrogen-containing analogs with H atoms. Reaction rate constants are measured at 300 K using a flowing afterglow-selected ion flow tube. We have implemented the laser induced acoustic desorption technique to allow the study of large, non-volatile species in the gas phase. The extension of this work from previous studies shows that the reactivity of polycyclic aromatic hydrocarbon cations with H atoms reaches a constant value for large cations. There is a small difference in reactivity when comparing molecules of different size and geometry; however, no difference in reactivity was found when nitrogen was incorporated into the ring.

  13. Catalytic Upgrading of Thermochemical Intermediates to Hydrocarbons: Conversion of Lignocellulosic Feedstocks to Aromatic Fuels and High Value Chemicals

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    3 May, 2013 Technology Area Review: Thermochemical Conversion Randy Cortright PhD Virent, Inc WBS: 3.3.1.10 This presentation does not contain any proprietary, confidential, or otherwise restricted information Goal Statement Project Goal -Develop and demonstrate integration of Virent's lignocellulosic biomass solvolysis technology with Virent's BioForming® process to generate aromatic-rich hydrocarbon products for use in either fuels or chemicals applications.  Liquefaction of Biomass and

  14. Anaerobic cometabolic transformation of polycyclic and heterocyclic aromatic hydrocarbons: evidence from laboratory and field studies

    SciTech Connect (OSTI)

    Michael Safinowski; Christian Griebler; Rainer U. Meckenstock

    2006-07-01

    The sulfate-reducing enrichment culture N47 can grow on naphthalene or 2-methylnaphthalene as the sole carbon and energy source. The study reported shows that the culture can furthermore cometabolically transform a variety of polycyclic and heteroaromatic compounds with naphthalene or methylnaphthalene as the auxiliary substrate. Most of the cosubstrates were converted to the corresponding carboxylic acids, frequently to several isomers. The mass spectra of specific metabolites that were extracted from supernatants of cultures containing the cosubstrates benzothiophene, benzofuran, and 1-methylnaphthalene resembled known intermediates of the anaerobic naphthalene and 2-methylnaphthalene degradation pathways. This indicates that some of the tested compounds were first methylated and then transformed to the corresponding methylsuccinic acids by a fumarate addition to the methyl group. For some of the cosubstrates, a partial or total inhibition of growth on the auxiliary substrate was observed. This was caused by a specific combination of auxiliary substrate and cosubstrate. None of the cosubstrates tested could be utilized as the sole carbon source and electron donor by the enrichment culture N47. Field investigations at the tar-oil-contaminated aquifer (at a former gasworks in southwest Germany), where strain N47 originated, revealed the presence of metabolites similar to the ones identified in batch culture supernatants. The findings suggest that aromatic hydrocarbons and heterocyclic compounds can be converted by aquifer organisms and produce a variety of polar compounds that become mobile in groundwater. 51 refs., 4 figs., 2 tabs.

  15. Real-time measurements of particulate matter and polycyclic aromatic hydrocarbon emissions from stationary combustion sources used in oil and gas production

    SciTech Connect (OSTI)

    D. w. Hahn; K. r. Hencken; H. A. Johnsen; J. R. Ross; P. M. Walsh

    1998-12-10

    Particulate matter emissions and some components of the particles were measured in the exhaust from combustion equipment used in oil and gas production operations near Bakersfield, California. The combustion sources included a 22.5 MW (electric) turbine generator, a 342-Bhp rich-burn spark ignition engine, and a 50 million Btu/h steam generator, all fired using natural gas. The particle components and measurement techniques were as follows: (1) Calcium, magnesium, sodium, silicon, and iron were measured using laser-induced breakdown spectroscopy (LIBS), (2) particle-bound polycyclic aromatic hydrocarbons (PAH) were detected using the charge produced by photoionization, (3) particles having sizes between 0.1 and 7.5 {micro}m were counted using an instrument based on light scattering, and (4) total particulate matter was measured according to US EPA Method 5. Not all of the methods were applied to all of the sources. Measurements were also made in the ambient air near the combustion air inlets to the units, for comparison with the concentrations in the exhaust, but the inlet and outlet measurements were not done simultaneously. Calcium, sodium, and silicon were found in the exhaust from the steam generator at concentrations similar to those in the ambient air near the inlet to the burner. Sodium and silicon were observed in the engine exhaust at levels a factor of four higher than their concentrations in the air. The principal metal observed in the engine exhaust was calcium, a component of the lubricating oil, at a concentration of 11.6 {micro}g/m{sup 3}. The air entering the gas turbine is filtered, so the average concentrations of metals in the turbine exhaust under steady operating conditions were even lower than in the air. During start-up following a shut-down to wash the turbine, silicon and iron were the major species in the stack, at concentrations of 6.4 and 16.2 {micro}g/m{sup 3}, respectively. A possible source of silicon is the water injected into the

  16. Generation and distribution of PAHs in the process of medical waste incineration

    SciTech Connect (OSTI)

    Chen, Ying; Zhao, Rongzhi; Xue, Jun; Li, Jinhui

    2013-05-15

    Highlights: ► PAHs generation and distribution features of medical waste incineration are studied. ► More PAHs were found in fly ash than that in bottom ash. ► The highest proportion of PAHs consisted of the seven most carcinogenic ones. ► Increase of free oxygen molecule and burning temperature promote PAHs degradation. ► There is a moderate positive correlation between total PCDD/Fs and total PAHs. - Abstract: After the deadly earthquake on May 12, 2008 in Wenchuan county of China, several different incineration approaches were used for medical waste disposal. This paper investigates the generation properties of polycyclic aromatic hydrocarbons (PAHs) during the incineration. Samples were collected from the bottom ash in an open burning slash site, surface soil at the open burning site, bottom ash from a simple incinerator, bottom ash generated from the municipal solid waste (MSW) incinerator used for medical waste disposal, and bottom ash and fly ash from an incinerator exclusively used for medical waste. The species of PAHs were analyzed, and the toxicity equivalency quantities (TEQs) of samples calculated. Analysis results indicate that the content of total PAHs in fly ash was 1.8 × 10{sup 3} times higher than that in bottom ash, and that the strongly carcinogenic PAHs with four or more rings accumulated sensitively in fly ash. The test results of samples gathered from open burning site demonstrate that Acenaphthylene (ACY), Acenaphthene (ACE), Fluorene (FLU), Phenanthrene (PHE), Anthracene (ANT) and other PAHs were inclined to migrate into surrounding environment along air and surface watershed corridors, while 4- to 6-ring PAHs accumulated more likely in soil. Being consistent with other studies, it has also been confirmed that increases in both free oxygen molecules and combustion temperatures could promote the decomposition of polycyclic PAHs. In addition, without the influence of combustion conditions, there is a positive correlation between

  17. Multi-photon UV photolysis of gaseous polycyclic aromatic hydrocarbons: Extinction spectra and dynamics

    SciTech Connect (OSTI)

    Walsh, A. J.; Gash, E. W.; Mansfield, M. W. D.; Ruth, A. A.

    2013-08-07

    The extinction spectra of static naphthalene and static biphenylene vapor, each buffered with a noble gas at room temperature, were measured as a function of time in the region between 390 and 850 nm after UV multi-photon laser photolysis at 308 nm. Employing incoherent broadband cavity enhanced absorption spectroscopy (IBBCEAS), the spectra were found to be unstructured with a general lack of isolated features suggesting that the extinction was not solely based on absorption but was in fact dominated by scattering from particles formed in the photolysis of the respective polycyclic aromatic hydrocarbon. Following UV multi-photon photolysis, the extinction dynamics of the static (unstirred) closed gas-phase system exhibits extraordinary quasi-periodic and complex oscillations with periods ranging from seconds to many minutes, persisting for up to several hours. Depending on buffer gas type and pressure, several types of dynamical responses could be generated (classified as types I, II, and III). They were studied as a function of temperature and chamber volume for different experimental conditions and possible explanations for the oscillations are discussed. A conclusive model for the observed phenomena has not been established. However, a number of key hypotheses have made based on the measurements in this publication: (a) Following the multi-photon UV photolysis of naphthalene (or biphenylene), particles are formed on a timescale not observable using IBBCEAS. (b) The observed temporal behavior cannot be described on basis of a chemical reaction scheme alone. (c) The pressure dependence of the system's responses is due to transport phenomena of particles in the chamber. (d) The size distribution and the refractive indices of particles are time dependent and evolve on a timescale of minutes to hours. The rate of particle coagulation, involving coalescent growth and particle agglomeration, affects the observed oscillations. (e) The walls of the chamber act as a sink

  18. Persistent activation of DNA damage signaling in response to complex mixtures of PAHs in air particulate matter

    SciTech Connect (OSTI)

    Jarvis, Ian W.H.; Bergvall, Christoffer; Bottai, Matteo; Westerholm, Roger; Stenius, Ulla; Dreij, Kristian

    2013-02-01

    Complex mixtures of polycyclic aromatic hydrocarbons (PAHs) are present in air particulate matter (PM) and have been associated with many adverse human health effects including cancer and respiratory disease. However, due to their complexity, the risk of exposure to mixtures is difficult to estimate. In the present study the effects of binary mixtures of benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) and complex mixtures of PAHs in urban air PM extracts on DNA damage signaling was investigated. Applying a statistical model to the data we observed a more than additive response for binary mixtures of BP and DBP on activation of DNA damage signaling. Persistent activation of checkpoint kinase 1 (Chk1) was observed at significantly lower BP equivalent concentrations in air PM extracts than BP alone. Activation of DNA damage signaling was also more persistent in air PM fractions containing PAHs with more than four aromatic rings suggesting larger PAHs contribute a greater risk to human health. Altogether our data suggests that human health risk assessment based on additivity such as toxicity equivalency factor scales may significantly underestimate the risk of exposure to complex mixtures of PAHs. The data confirms our previous findings with PAH-contaminated soil (Niziolek-Kierecka et al., 2012) and suggests a possible role for Chk1 Ser317 phosphorylation as a biological marker for future analyses of complex mixtures of PAHs. -- Highlights: ? Benzo[a]pyrene (BP), dibenzo[a,l]pyrene (DBP) and air PM PAH extracts were compared. ? Binary mixture of BP and DBP induced a more than additive DNA damage response. ? Air PM PAH extracts were more potent than toxicity equivalency factor estimates. ? Larger PAHs (> 4 rings) contribute more to the genotoxicity of PAHs in air PM. ? Chk1 is a sensitive marker for persistent activation of DNA damage signaling from PAH mixtures.

  19. Fusing porphyrins with polycyclic aromatic hydrocarbons and heterocycles for optoelectronic applications

    DOE Patents [OSTI]

    Thompson, Mark E.; Diev, Viacheslav; Hanson, Kenneth; Forrest, Stephen R.

    2015-08-18

    A compound that can be used as a donor material in organic photovoltaic devices comprising a non-activated porphyrin fused with one or more non-activated polycyclic aromatic rings or one or more non-activated heterocyclic rings can be obtained by a thermal fusion process. The compounds can include structures of Formula I: ##STR00001## By heating the reaction mixture of non-activated porphyrins with non-activated polycyclic aromatic rings or heterocyclic rings to a fusion temperature and holding for a predetermined time, fusion of one or more polycyclic rings or heterocyclic rings to the non-activated porphyrin core in meso,.beta. fashion is achieved resulting in hybrid structures containing a distorted porphyrin ring with annulated aromatic rings. The porphyrin core can be olygoporphyrins.

  20. Electron correlations and two-photon states in polycyclic aromatic hydrocarbon molecules: A peculiar role of geometry

    SciTech Connect (OSTI)

    Aryanpour, Karan; Shukla, Alok; Mazumdar, Sumit; College of Optical Sciences, University of Arizona, Tucson, Arizona 85721

    2014-03-14

    We present numerical studies of one- and two-photon excited states ordering in a number of polycyclic aromatic hydrocarbon molecules: coronene, hexa-peri-hexabenzocoronene, and circumcoronene, all possessing D{sub 6h} point group symmetry versus ovalene with D{sub 2h} symmetry, within the Pariser-Parr-Pople model of interacting ?-electrons. The calculated energies of the two-photon states as well as their relative two-photon absorption cross-sections within the interacting model are qualitatively different from single-particle descriptions. More remarkably, a peculiar role of molecular geometry is found. The consequence of electron correlations is far stronger for ovalene, where the lowest spin-singlet two-photon state is a quantum superposition of pairs of lowest spin triplet states, as in the linear polyenes. The same is not true for D{sub 6h} group hydrocarbons. Our work indicates significant covalent character, in valence bond language, of the ground state, the lowest spin triplet state and a few of the lowest two-photon states in D{sub 2h} ovalene but not in those with D{sub 6h} symmetry.

  1. PAH bioconcentration in Mytilus sp from Sinclair Inlet, WA

    SciTech Connect (OSTI)

    Frazier, J.; Young, D.; Ozretich, R.; Echols, S.

    1995-12-31

    Approximately 20 polynuclear aromatic hydrocarbons (PAH) were measured by GC/MS in seawater and whole soft tissues of the intertidal mussel Mytilus sp. collected in July 1991 within and around Puget Sound`s Sinclair Inlet. Low variability was observed in the water concentrations collected over three days at control sites, yielding reliable values for the exposure levels experienced by this bioindicator mollusk. Mean water concentrations of acenaphthene, phenanthrene, and fluoranthene in the control region were 2.7 {+-} 0.8, 2.8 {+-} 0.8, and 3.1 {+-} 0.7 ng/liter, respectively. Levels measured near sites of vessel activity were higher but much more variable; this reduced the reliability of the tissue/water bioconcentration factors (BCF) obtained from these samples. An empirical model relating values of Log BCF and Log Kow for the control zone samples supports the utility of this estuarine bioindicator for monitoring general levels of PAH in nearshore surface waters.

  2. On-line instrumentation for the real-time monitoring of polynuclear aromatic hydrocarbons in the effluents from a fluidized bed combustor - a feasibility study

    SciTech Connect (OSTI)

    D'Silva, A.P.; Iles, M.; Rice, G.; Fassel, V.A.

    1984-04-01

    When polynuclear aromatic hydrocargons in the vapor phase are diluted preferably in a rare gas and undergo supersonic jet expansion, rotationally cooled molecules with absorption bandwidths of the order of 0.01 nm (FWHM) are obtained. Selective excitation with a tunable dye laser into such narrow absorption bands leads to the observation of highly specific luminescence spectra. Such an approach has been utilized for the on-line, real-time monitoring of polynuclear aromatic hydrocarbons in the effluents from a fluidized bed combustor.

  3. RECONSTRUCTING THE STELLAR MASS DISTRIBUTIONS OF GALAXIES USING S{sup 4}G IRAC 3.6 AND 4.5 {mu}m IMAGES. I. CORRECTING FOR CONTAMINATION BY POLYCYCLIC AROMATIC HYDROCARBONS, HOT DUST, AND INTERMEDIATE-AGE STARS

    SciTech Connect (OSTI)

    Meidt, Sharon E.; Schinnerer, Eva; Bosma, Albert; Athanassoula, E.; Sheth, Kartik; Munoz-Mateos, Juan-Carlos; Buta, Ronald J.; Zaritsky, Dennis; Hinz, Joannah L.; Skibba, Ramin A.; Laurikainen, Eija; Salo, Heikki; Elmegreen, Debra; Elmegreen, Bruce G.; Gadotti, Dimitri A.; Regan, Michael; Ho, Luis C.; Madore, Barry F.; Gil de Paz, Armando; and others

    2012-01-01

    With the aim of constructing accurate two-dimensional maps of the stellar mass distribution in nearby galaxies from Spitzer Survey of Stellar Structure in Galaxies 3.6 and 4.5 {mu}m images, we report on the separation of the light from old stars from the emission contributed by contaminants. Results for a small sample of six disk galaxies (NGC 1566, NGC 2976, NGC 3031, NGC 3184, NGC 4321, and NGC 5194) with a range of morphological properties, dust content, and star formation histories are presented to demonstrate our approach. To isolate the old stellar light from contaminant emission (e.g., hot dust and the 3.3 {mu}m polycyclic aromatic hydrocarbon (PAH) feature) in the IRAC 3.6 and 4.5 {mu}m bands we use an independent component analysis (ICA) technique designed to separate statistically independent source distributions, maximizing the distinction in the [3.6]-[4.5] colors of the sources. The technique also removes emission from evolved red objects with a low mass-to-light ratio, such as asymptotic giant branch (AGB) and red supergiant (RSG) stars, revealing maps of the underlying old distribution of light with [3.6]-[4.5] colors consistent with the colors of K and M giants. The contaminants are studied by comparison with the non-stellar emission imaged at 8 {mu}m, which is dominated by the broad PAH feature. Using the measured 3.6 {mu}m/8 {mu}m ratio to select individual contaminants, we find that hot dust and PAHs together contribute between {approx}5% and 15% to the integrated light at 3.6 {mu}m, while light from regions dominated by intermediate-age (AGB and RSG) stars accounts for only 1%-5%. Locally, however, the contribution from either contaminant can reach much higher levels; dust contributes on average 22% to the emission in star-forming regions throughout the sample, while intermediate-age stars contribute upward of 50% in localized knots. The removal of these contaminants with ICA leaves maps of the old stellar disk that retain a high degree of

  4. In-situ Phytoremediation of PAH and PCB Contaminated Marine Sediments with Eelgrass (Zostera marina)

    SciTech Connect (OSTI)

    Huesemann, Michael H.; Hausmann, Tom S.; Fortman, Timothy J.; Thom, Ronald M.; Cullinan, Valerie I.

    2009-10-01

    In view of the fact that there are presently no cost-effective in-situ treatment technologies for contaminated sediments, a 60 week long phytoremediation feasibility study was conducted in seawater-supplied outdoor ponds to determine whether eelgrass (Zostera marina) is capable of removing polynuclear aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) from submerged marine sediments. It was determined that all PAHs and PCBs, independent of the number of aromatic rings and degree of chlorination, respectively, were removed to a much larger extent in planted sediments compared to unplanted controls. After 60 weeks of treatment, the concentration of total PAHs decreased by 73% in planted sediments but only 25% in unplanted controls. Similarly, total PCBs declined by 60% in the presence of plants while none were removed in the unplanted sediment. Overall, PAH and PCB biodegradation was greatest in the sediment layer that contained most of the eelgrass roots. Abiotic desorption tests conducted at week 32 confirmed that the phytoremediation process was not controlled by mass-transfer or bioavailability limitations since all PAHs and PCBs desorbed rapidly and to a large extent from the sediment. PAHs were detected in both roots and shoots, with root and shoot bioaccumulation factors for total PAHs amounting to approximately 3 and 1, respectively, after 60 weeks of phytoremediation treatment. Similarly, the root bioccumulation factor for total PCBs was around 4, while no PCBs were detected in the eelgrass leaves at the end of the experiment. The total mass fraction of PAHs and PCBs absorbed and translocated by plant biomass during the 60 week period was insignificant, amounting to less than 0.5% of the total mass of PAHs and PCBs which was initially present in the sediment. Finally, the number of total heterotrophic bacteria and hydrocarbon degraders was slightly but not statistically significantly greater in planted sediments than in unplanted controls

  5. Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges

    SciTech Connect (OSTI)

    Castaldi, F.J.; Bombaugh, K.J.; McFarland, B.

    1995-12-31

    Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material was more pronounced under aerobic metabolic conditions than under strict anaerobic conditions. The changes in the hydrocarbon molecular weight distribution, infrared spectra, and PAH concentrations during slurry-phase treatment indicate that the aerobic thermophilic bioslurry achieved a higher degree of hydrocarbon degradation than the anaerobic thermophilic bioslurry during the same time period.

  6. PAHs content of sewage sludge in Europe and its use as soil fertilizer

    SciTech Connect (OSTI)

    Suciu, Nicoleta A. Lamastra, Lucrezia; Trevisan, Marco

    2015-07-15

    Highlights: • Sewage sludge contamination by PAHs may restrict its use as soil fertilizer. • Long term data concerning sewage sludge contamination by PAHs is lacking. • Literature review for EU countries and monitoring data for Italy is presented. • Focus PEARL model was used to simulate B(a)Pyr, the most toxic PAH, fate in soil. • The simulated B(a)Pyr soil concentration was much lower than its LOEC for soil organisms. - Abstract: The European Commission has been planning limits for organic pollutants in sewage sludge for 14 years; however no legislation has been implemented. This is mainly due to lack of data on sewage sludge contamination by organic pollutants, and possible negative effects to the environment. However, waste management has become an acute problem in many countries. Management options require extensive waste characterization, since many of them may contain compounds which could be harmful to the ecosystem, such as heavy metals, organic pollutants. The present study aims to show the true European position, regarding the polycyclic aromatic hydrocarbons (PAHs) content of sewage sludge, by comparing the Italian PAHs content with European Union countries, and at assessing the suitability of sewage sludge as soil fertilizer. The FOCUS Pearl model was used to estimate the concentration of benzo [a] pyrene (B(a)Pyr), the most toxic PAH in soil, and its exposure to organisms was then evaluated. The simulated B(a)Pyr and PAHs, expressed as B(a)Pyr, concentrations in soil were much lower than the B(a)Pyr’s most conservative lowest observable effect concentration (LOEC) for soil organisms. Furthermore, the results obtained indicate that it is more appropriate to apply 5 t ha{sup −1} sewage sludge annually than 15 t ha{sup −1} triennially. Results suggest, the EU maximum recommended limit of 6 mg kg{sup −1} PAHs in sewage sludge, should be conservative enough to avoid groundwater contamination and negative effects on soil organisms.

  7. Mechanism-based classification of PAH mixtures to predict carcinogenic potential

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

    Tilton, Susan C.; Siddens, Lisbeth K.; Krueger, Sharon K.; Larkin, Andrew J.; Löhr, Christiane V.; Williams, David E.; Baird, William M.; Waters, Katrina M.

    2015-04-22

    We have previously shown that relative potency factors and DNA adduct measurements are inadequate for predicting carcinogenicity of certain polycyclic aromatic hydrocarbons (PAHs) and PAH mixtures, particularly those that function through alternate pathways or exhibit greater promotional activity compared to benzo[a]pyrene (BaP). Therefore, we developed a pathway based approach for classification of tumor outcome after dermal exposure to PAH/mixtures. FVB/N mice were exposed to dibenzo[def,p]chrysene (DBC), BaP or environmental PAH mixtures (Mix 1-3) following a two-stage initiation/promotion skin tumor protocol. Resulting tumor incidence could be categorized by carcinogenic potency as DBC>>BaP=Mix2=Mix3>Mix1=Control, based on statistical significance. Gene expression profiles measured inmore » skin of mice collected 12 h post-initiation were compared to tumor outcome for identification of short-term bioactivity profiles. A Bayesian integration model was utilized to identify biological pathways predictive of PAH carcinogenic potential during initiation. Integration of probability matrices from four enriched pathways (p<0.05) for DNA damage, apoptosis, response to chemical stimulus and interferon gamma signaling resulted in the highest classification accuracy with leave-one-out cross validation. This pathway-driven approach was successfully utilized to distinguish early regulatory events during initiation prognostic for tumor outcome and provides proof-of-concept for using short-term initiation studies to classify carcinogenic potential of environmental PAH mixtures. As a result, these data further provide a ‘source-to outcome’ model that could be used to predict PAH interactions during tumorigenesis and provide an example of how mode-of-action based risk assessment could be employed for environmental PAH mixtures.« less

  8. Mechanism-based classification of PAH mixtures to predict carcinogenic potential

    SciTech Connect (OSTI)

    Tilton, Susan C.; Siddens, Lisbeth K.; Krueger, Sharon K.; Larkin, Andrew J.; Löhr, Christiane V.; Williams, David E.; Baird, William M.; Waters, Katrina M.

    2015-04-22

    We have previously shown that relative potency factors and DNA adduct measurements are inadequate for predicting carcinogenicity of certain polycyclic aromatic hydrocarbons (PAHs) and PAH mixtures, particularly those that function through alternate pathways or exhibit greater promotional activity compared to benzo[a]pyrene (BaP). Therefore, we developed a pathway based approach for classification of tumor outcome after dermal exposure to PAH/mixtures. FVB/N mice were exposed to dibenzo[def,p]chrysene (DBC), BaP or environmental PAH mixtures (Mix 1-3) following a two-stage initiation/promotion skin tumor protocol. Resulting tumor incidence could be categorized by carcinogenic potency as DBC>>BaP=Mix2=Mix3>Mix1=Control, based on statistical significance. Gene expression profiles measured in skin of mice collected 12 h post-initiation were compared to tumor outcome for identification of short-term bioactivity profiles. A Bayesian integration model was utilized to identify biological pathways predictive of PAH carcinogenic potential during initiation. Integration of probability matrices from four enriched pathways (p<0.05) for DNA damage, apoptosis, response to chemical stimulus and interferon gamma signaling resulted in the highest classification accuracy with leave-one-out cross validation. This pathway-driven approach was successfully utilized to distinguish early regulatory events during initiation prognostic for tumor outcome and provides proof-of-concept for using short-term initiation studies to classify carcinogenic potential of environmental PAH mixtures. As a result, these data further provide a ‘source-to outcome’ model that could be used to predict PAH interactions during tumorigenesis and provide an example of how mode-of-action based risk assessment could be employed for environmental PAH mixtures.

  9. Mechanism-based classification of PAH mixtures to predict carcinogenic potential

    SciTech Connect (OSTI)

    Tilton, Susan C.; Siddens, Lisbeth K.; Krueger, Sharon K.; Larkin, Andrew J.; Lhr, Christiane V.; Williams, David E.; Baird, William M.; Waters, Katrina M.

    2015-04-22

    We have previously shown that relative potency factors and DNA adduct measurements are inadequate for predicting carcinogenicity of certain polycyclic aromatic hydrocarbons (PAHs) and PAH mixtures, particularly those that function through alternate pathways or exhibit greater promotional activity compared to benzo[a]pyrene (BaP). Therefore, we developed a pathway based approach for classification of tumor outcome after dermal exposure to PAH/mixtures. FVB/N mice were exposed to dibenzo[def,p]chrysene (DBC), BaP or environmental PAH mixtures (Mix 1-3) following a two-stage initiation/promotion skin tumor protocol. Resulting tumor incidence could be categorized by carcinogenic potency as DBC>>BaP=Mix2=Mix3>Mix1=Control, based on statistical significance. Gene expression profiles measured in skin of mice collected 12 h post-initiation were compared to tumor outcome for identification of short-term bioactivity profiles. A Bayesian integration model was utilized to identify biological pathways predictive of PAH carcinogenic potential during initiation. Integration of probability matrices from four enriched pathways (p<0.05) for DNA damage, apoptosis, response to chemical stimulus and interferon gamma signaling resulted in the highest classification accuracy with leave-one-out cross validation. This pathway-driven approach was successfully utilized to distinguish early regulatory events during initiation prognostic for tumor outcome and provides proof-of-concept for using short-term initiation studies to classify carcinogenic potential of environmental PAH mixtures. As a result, these data further provide a source-to outcome model that could be used to predict PAH interactions during tumorigenesis and provide an example of how mode-of-action based risk assessment could be employed for environmental PAH mixtures.

  10. Strong sorption of native PAHs to pyrogenic and unburned carbonaceous geosorbents in sediments

    SciTech Connect (OSTI)

    Gerard Cornelissen; Gijs D. Breedveld; Stavros Kalaitzidis; Kimon Christanis; Anne Kibsgaard; Amy M.P. Oen

    2006-02-15

    It has recently been shown that the presence of carbonaceous geosorbents (CG, including black carbon (BC), unburned coal, and kerogen) can cause strong sorption of polycyclic aromatic hydrocarbons (PAHs) in sediments. The authors studied sorption of native PAHs in four Norwegian harbor sediments of which high fractions (21-56%) of the total organic carbon (TOC) consisted of CG carbon (CGC), as shown by organic petrography. PAH sorption coefficients were 1-2 orders of magnitude above predictions based on amorphous organic carbon partitioning alone. In recent studies, such strong sorption was attributed solely to BC sorption under the implicit assumption that sorption is linear for coal and kerogen. The most important result of the present study is that total sorption is better explained by considering all three nonlinearly sorbing CGC materials than by only considering BC. In addition, it was evaluated whether activated carbon (AC) amendments could be effective in reducing the freely dissolved porewater concentrations (C{sub W}) and thus the environmental risks of the PAHs in such strongly sorbing sediments. The results indicated that an addition of 2 weight % AC reduced the C{sub W} by factors of 21-153 for the four sediments (average values for all PAHs). It was shown that phenanthrene sorption to AC was, on average, reduced by a factor of 6 in sediment-AC mixtures compared to pure AC. 33 refs., 5 figs., 2 tabs.

  11. HYDROGENATION OF PAH CATIONS: A FIRST STEP TOWARD H{sub 2} FORMATION

    SciTech Connect (OSTI)

    Boschman, L.; Cazaux, S.; Spaans, M.; Reitsma, G.; Schlathoelter, T.; Hoekstra, R.; Gonzalez-Magana, O.

    2012-12-20

    Molecular hydrogen is the most abundant molecule in the universe. A large fraction of H{sub 2} forms by association of hydrogen atoms adsorbed on polycyclic aromatic hydrocarbons (PAHs), where formation rates depend crucially on the H sticking probability. We have experimentally studied PAH hydrogenation by exposing coronene cations, confined in a radio-frequency ion trap, to gas phase atomic hydrogen. A systematic increase of the number of H atoms adsorbed on the coronene with the time of exposure is observed. Odd coronene hydrogenation states dominate the mass spectrum up to 11 H atoms attached. This indicates the presence of a barrier preventing H attachment to these molecular systems. For the second and fourth hydrogenations, barrier heights of 72 {+-} 6 meV and 40 {+-} 10 meV, respectively, are found, which are in good agreement with theoretical predictions for the hydrogenation of neutral PAHs. Our experiments, however, prove that the barrier does not vanish for higher hydrogenation states. These results imply that PAH cations, as their neutral counterparts, exist in highly hydrogenated forms in the interstellar medium. Due to this catalytic activity, PAH cations and neutrals seem to contribute similarly to the formation of H{sub 2}.

  12. 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.

  13. Catalytic hydroprocessing of simulated heavy coal liquids; 1: Reactivities of aromatic hydrocarbons and sulfur and oxygen heterocyclic compounds

    SciTech Connect (OSTI)

    Girgis, M.J. . Dept. of Chemical Engineering Mobil Research and Development Corp., Princeton, NJ . Central Research Lab.); Gates, B.C. . Dept. of Chemical Engineering)

    1994-05-01

    The hydroprocessing of mixtures simulating a coal liquid without organonitrogen compounds was investigated with a once-through flow reactor operated with liquid-phase reactants at 350 C and 171 atm. The catalyst was sulfided Ni-Mo/[gamma]-Al[sub 2]O[sub 3]. The reactants included pyrene, phenanthrene, fluoranthene, dibenzothiophene, dibenzofuran, and 5,6,7,8-tetrahydro-1-naphthol. The products formed from each reactant were determined, and each reaction was modeled as first order in the organic reactant. The reactivity of fused six-ring aromatics increases with the number of rings, but the change from one member of the family to another is less than the order-of-magnitude increase in reactivity from benzene to naphthalene. Fluoranthene must be considered in a separate compound class from fused six-membered-ring aromatics because it is hydrogenated more rapidly. Dibenzothiophene gives biphenyl selectively. Dibenzofuran reacts very slowly, whereas 5,6,7,8-tetrahydro-1-naphthol reacts very rapidly. The results reported here, in combination with the reaction networks developed in the sequel, are the first quantitative evaluation of reactivities of components in a mixture simulating a hydroprocessing feedstock that takes account of competitive reactions and the formation of intermediate products.

  14. Immunomodulation in C57Bl/6 mice following consumption of halogenated aromatic hydrocarbon-contaminated coho salmon (Oncorhynchus kisutch) from Lake Ontario

    SciTech Connect (OSTI)

    Cleland, G.B.; McElroy, P.J.; Sonstegard, R.A. )

    1989-01-01

    This report describes studies designed to assess the immunomodulatory effects associated with the consumption of coho salmon containing halogenated aromatic hydrocarbons (HAHs) and other compounds naturally bioaccumulated from Lake Ontario. Diets containing 33% coho salmon from Lake Ontario or the Pacific Ocean were fed to juvenile C57Bl/6 mice for 2-4 mo. Following 60 d, the mice that consumed Lake Ontario salmon had reduced IgM, IgG, and IgA plaque-forming cell responses to sheep erythrocytes. No changes were observed in total numbers of spleen lymphocytes, total T-lymphocytes or T-lymphocyte subsets as determined by flow cytometry. Cellular immunity, assessed by the cytotoxic T-lymphocyte response to allogeneic tumor target cells, was not altered following dietary exposure to Lake Ontario coho salmon for 4 mo. The observed humoral immunomodulation correlated with elevated PCB levels in the Lake Ontario salmon diets. The levels of pollutants such as mercury, tin compounds and other metals, PCDDs, and PCDFs were not examined.

  15. Toxic effects in C57B1/6 and DBA/2 mice following consumption of halogenated aromatic hydrocarbon-contaminated Great Lakes coho salmon (Oncorhynchus kisutch Walbaum)

    SciTech Connect (OSTI)

    Cleland, G.B.; Leatherland, J.F.; Sonstegard, R.A.

    1987-11-01

    Diets containing coho salmon (Oncorhynchus kisutch Walbaum) from the Pacific Ocean or from Lakes Erie, Michigan, and Ontario (containing a gradation from low to high of halogenated aromatic hydrocarbons, (HAHs)) were fed to C57B1/6 and DBA/2 mice. Following a 4-month dietary exposure to Lake Ontario salmon, both strains of mice demonstrated hepatomegaly. The ethoxyresorufin-O-deethylase (ERR) enzyme levels were elevated in livers of C57B1/6 mice fed diets of salmon from all of the Great Lakes studied, with exceptionally high levels detected in C57B1/6 mice fed Lake Ontario salmon. Induction of ERR enzyme levels was detected in DBA/2 mice only following dietary exposure to Lake Ontario salmon. Serum levels of L-thyroxine (T4) and triiodo-L-thryonine (T3) were suppressed in C57B1/6 mice following consumption of Lake Ontario coho salmon, but T3 and T4 levels remained unchanged in DBA/2 mice. In general, pathobiological effects correlated with both dietary HAH exposure level and Ah receptor status.

  16. Significance of Cytochrome P450 System Responses and Levels of Bile Fluorescent Aromatic Compounds in Marine Wildlife Following Oil Spills

    SciTech Connect (OSTI)

    Lee, Richard F.; Anderson, Jack W.

    2005-07-01

    The relationships among cytochrome P450 induction in marine wildlife species, levels of fluorescent aromatic compounds (FAC) in their bile, the chemical composition of the inducing compounds, the significance of the exposure pathway, and any resulting injury, as a consequence of exposure to crude oil following a spill, are reviewed. Fish collected after oil spills often show increases in cytochrome P450 system activity, cytochrome P4501A (CYP1A) and bile fluorescent aromatic compounds (FAC), that are correlated with exposure to polycyclic aromatic hydrocarbons (PAH) in the oil. There is also some evidence for increases in bile FAC and induction of cytochrome P450 in marine birds and mammals after oil spills. However, when observed, increases in these exposure indicators are transitory and generally decrease to background levels within one year after the exposure. Laboratory studies have shown induction of cytochrome P450 systems occurs after exposure of fish to crude oil in water, sediment or food. Most of the PAH found in crude oil (dominantly 2- and 3-ring PAH) are not strong inducers of cytochrome P450. Exposure to the 4-ring chrysenes or the photooxidized products of the PAH may account for the cytochrome P450 responses in fish collected from oil-spill sites. The contribution of non-spill background PAH, particularly combustion-derived (pyrogenic) PAH, to bile FAC and cytochrome P450 system responses can be confounding and needs to be considered when evaluating oil spill effects. The ubiquity of pyrogenic PAH makes it important to fully characterize all sources of PAH, including PAH from natural resources, e.g. retene, in oil spill studies. In addition, such parameters as species, sex, age, ambient temperature and season need to be taken into account. While increases in fish bile FAC and cytochrome P450 system responses, can together, be sensitive general indicators of PAH exposure after an oil spill, there is little unequivocal evidence to suggest a linkage to

  17. Petroleum hydrocarbons in near-surface seawater of Prince William Sound, Alaska, following the Exxon Valdez oil spill II: Analysis of caged mussels. Air/water study number 3. Subtidal study number 3a. Exxon Valdez oil spill state/federal natural resource damage assessment final report

    SciTech Connect (OSTI)

    Short, J.W.; Harris, P.M.

    1995-07-01

    Mussels (Mytilus trossulus) were deployed at 22 locations inside Prince William Sound and 16 locations outside the Sound at depths of 1, 5 and 25 m for 2 to 8 weeks to determine the biological availability and persistence of petroleum-derived hydrocarbons from the Exxon Valdez Oil (EVO) spill. Four successive deployments were made in 1989, and two each in 1990 and 1991. Mussels were analyzed for 27 alkane and 43 polynuclear aromatic hydrocarbon (PAH) analytes. PAH concentrations derived from EVO in mussels decreased with depth, time, and distance from heavily oiled beaches. Hydrocarbon accumulation derived from EVO by deployed mussels indicates petroleum hydrocarbons were available to subsurface marine fauna the summer following the spill, which may be a route of oil ingestion exposure by fauna at high trophic levels.

  18. THE AROMATIC FEATURES IN VERY FAINT DWARF GALAXIES

    SciTech Connect (OSTI)

    Wu Ronin; Hogg, David W.; Moustakas, John

    2011-04-01

    We present optical and mid-infrared photometry of a statistically complete sample of 29 dwarf galaxies (M{sub r} > - 15 mag) selected from the Sloan Digital Sky Survey (SDSS) spectroscopic sample and observed in the mid-infrared with Spitzer IRAC. This sample contains nearby (redshift {approx}<0.005) galaxies 3 mag fainter than previously studied samples. We compare our sample with other star-forming galaxies that have been observed with both IRAC and SDSS. We examine the relationship of the infrared color, [3.6]-[7.8], sensitive to polycyclic aromatic hydrocarbon (PAH) abundance and also hot dust and stellar continuum, with star formation rates (SFRs), oxygen abundances, and radiation hardness, all estimated by optical emission lines. Consistent with studies of more luminous dwarfs, we find that these dwarf galaxies show much redder [3.6]-[7.8] color than luminous galaxies with similar specific SFRs. Unlike luminous galaxies, we find that these dwarf galaxies show no significant dependence at all of the [3.6]-[7.8] color on SFR, oxygen abundance, or radiation hardness, despite the fact that the sample spans a significant range in all of these quantities. When the dwarfs in our sample are compared with more luminous dwarfs, we find that the [3.6]-[7.8] color, potentially tracing the PAH emission, depends on oxygen abundance and radiation hardness. However, these two parameters are correlated with one another as well; we break this degeneracy by looking at the PAH-oxygen abundance relation at a fixed radiation hardness and the PAH-hardness relation at a fixed oxygen abundance. This test shows that the [3.6]-[7.8] color in dwarf galaxies appears to depend more directly on oxygen abundance based on the data currently available.

  19. 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)

  20. THE NASA AMES PAH IR SPECTROSCOPIC DATABASE VERSION 2.00: UPDATED CONTENT, WEB SITE, AND ON(OFF)LINE TOOLS

    SciTech Connect (OSTI)

    Boersma, C.; Mattioda, A. L.; Allamandola, L. J.; Bauschlicher, C. W. Jr.; Ricca, A.; Cami, J.; Peeters, E.; De Armas, F. Sánchez; Saborido, G. Puerta; Hudgins, D. M.

    2014-03-01

    A significantly updated version of the NASA Ames PAH IR Spectroscopic Database, the first major revision since its release in 2010, is presented. The current version, version 2.00, contains 700 computational and 75 experimental spectra compared, respectively, with 583 and 60 in the initial release. The spectra span the 2.5-4000 μm (4000-2.5 cm{sup -1}) range. New tools are available on the site that allow one to analyze spectra in the database and compare them with imported astronomical spectra as well as a suite of IDL object classes (a collection of programs utilizing IDL's object-oriented programming capabilities) that permit offline analysis called the AmesPAHdbIDLSuite. Most noteworthy among the additions are the extension of the computational spectroscopic database to include a number of significantly larger polycyclic aromatic hydrocarbons (PAHs), the ability to visualize the molecular atomic motions corresponding to each vibrational mode, and a new tool that allows one to perform a non-negative least-squares fit of an imported astronomical spectrum with PAH spectra in the computational database. Finally, a methodology is described in the Appendix, and implemented using the AmesPAHdbIDLSuite, that allows the user to enforce charge balance during the fitting procedure.

  1. Mass transfer and biodegradation of PAH compounds from coal tar. Quarterly technical report, January--March 1993

    SciTech Connect (OSTI)

    Ramaswami, A.; Ghoshal, S.; Luthy, R.G.

    1994-09-01

    This study examines the role of physico-chemical mass transfer processes on the rate of biotransformation of polycyclic aromatic hydrocarbon (PAH) compounds released from non-aqueous phase liquid (NAPL) coal tar present at residual saturation within a microporous medium. A simplified coupled dissolution-degradation model is developed that describes the concurrent mass transfer and biokinetic processes occurring in the system. Model results indicate that a dimensionless Damkohler number can be utilized to distinguish between systems that are mass transfer limited, and those that are limited by biological phenomena. The Damkohler number is estimated from independent laboratory experiments that measure the rates of aqueous phase dissolution and biodegradation of naphthalene from coal tar. Experimental data for Stroudsburg coal tar imbibed within 236 {mu}m diameter silica particles yield Damkohler numbers smaller than unity, indicating, for the particular system under study, that the overall rate of biotransformation of naphthalene is not limited by the mass transfer of naphthalene from coal tar to the bulk aqueous phase. There is a need for investigation of mass transfer for larger particles and/or other PAH compounds, and study of microbial rate-limiting phenomena including toxicity, inhibition and competitive substrate utilization.

  2. Effects of the furnace temperature on the CO, CO{sub 2}, NO{sub x} and unburned hydrocarbon emissions from the combustion of coal and alternative fuels

    SciTech Connect (OSTI)

    Levendis, Y.A.; Atal, A.; Courtemanche, B.

    1999-07-01

    Results are presented on the emissions of carbon monoxide (CO), carbon dioxide (CO{sub 2}), unburned aromatic hydrocarbons, as well as oxides of nitrogen (NO{sub x}) from the combustion of pulverized bituminous coal, tire-derived fuel and, for a limited number of runs, waste plastics-derived fuel. The particle size cuts of pulverized coal, tire and plastics were 63--75 {micro}m and 180--300 {micro}m, respectively. Combustion experiments were conducted in a laboratory-scale drop-tube furnace at gas temperatures, in the range of 1,300--1,600 K, and several fuel mass loadings in the furnace, expressed in terms of global equivalence ratios in the range of 0.4--2.4. The CO, CO{sub 2} and NO{sub x} emissions were monitored continuously with infrared absorption and chemiluminescent instruments. Up to sixty 2-7 ring polynuclear aromatic hydrocarbons (PAH) were detected by capillary gas chromatography - mass spectrometry (GC-MS) techniques. Results showed that the PAH emission yields (mg/g fuel introduced) increased drastically with increasing bulk equivalence ratio (in the aforementioned range), at fixed furnace temperatures. This was also true for the CO yields, while the CO{sub 2} yields increased with increasing {o}, reached a maximum around stoichiometry and then decreased mildly. NO{sub x} yields decreased precipitously with increasing equivalence ratio. The CO and, especially, the PAH yields from tire-derived and plastics-derived fuels were much higher than those from coal, but the relative amounts of individual PAH components were remarkably similar in the combustion effluent of all fuels. The CO{sub 2} emissions and, especially, the NO{sub x} emissions from tire crumb were lower than those from coal. The CO{sub 2} emissions from plastics were comparable to those from coal, but their NO {sub x} emissions were much lower than those from tire. At fixed bulk equivalence ratios, however, as the furnace gas temperature increased the PAH yields from coal, tire crumb, and

  3. Determination of PAH in SRM 1582, Wilmington crude oil

    SciTech Connect (OSTI)

    Not Available

    1982-12-13

    The concentrations of phenanthrene, fluoranthene, pyrene, benz(a)anthracene, benzo(a)pyrene, and perylene have been measured in SRM 1582 using the sequential HPLC procedure that was used in the certification PAH in SRM 1580, ''Organics in Shale Oil''. Quantification was accomplished through use of perdeuterated internal standards which were spiked into the oil sample at concentrations similar to that of the analyte compounds. The instrumentation used in these analyses is listed in Table I. The internal standard used for each analyte is identified in Table II. Perdeuterated analogs of the parent PAH serve as excellent internal standards because they have the same number of aromatic carbons and therefore co-elute on the aminosilane column. The perdeuterated PAH compound is resolved chromatographically from the parent PAH compound on the C/sub 18/ column, with the internal standard eluting just prior to the parent. The perdeuterated and parent compounds have similar fluorescence excitation and emission spectra as shown by the fact that their relative response factors are close to unity. Calibration solutions containing both the internal standard and analyte compounds were prepared for each compound to be determined. The concentration of the analyte compound in these solutions was routinely verified by comparison with SRM 1647. 1 ref., 8 tabs.

  4. Comparative developmental toxicity of environmentally relevant oxygenated PAHs

    SciTech Connect (OSTI)

    Knecht, Andrea L.; Goodale, Britton C.; Truong, Lisa; Simonich, Michael T.; Swanson, Annika J.; Matzke, Melissa M.; Anderson, Kim A.; Waters, Katrina M.; Tanguay, Robert L.

    2013-09-01

    Oxygenated polycyclic aromatic hydrocarbons (OPAHs) are byproducts of combustion and photo-oxidation of parent PAHs. OPAHs are widely present in the environment and pose an unknown hazard to human health. The developing zebrafish was used to evaluate a structurally diverse set of 38 OPAHs for malformation induction, gene expression changes and mitochondrial function. Zebrafish embryos were exposed from 6 to 120 h post fertilization (hpf) to a dilution series of 38 different OPAHs and evaluated for 22 developmental endpoints. AHR activation was determined via CYP1A immunohistochemistry. Phenanthrenequinone (9,10-PHEQ), 1,9-benz-10-anthrone (BEZO), xanthone (XAN), benz(a)anthracene-7,12-dione (7,12-B[a]AQ), and 9,10-anthraquinone (9,10-ANTQ) were evaluated for transcriptional responses at 48 hpf, prior to the onset of malformations. qRT-PCR was conducted for a number of oxidative stress genes, including the glutathione transferase(gst), glutathione peroxidase(gpx), and superoxide dismutase(sod) families. Bioenergetics was assayed to measure in vivo oxidative stress and mitochondrial function in 26 hpf embryos exposed to OPAHs. Hierarchical clustering of the structure-activity outcomes indicated that the most toxic of the OPAHs contained adjacent diones on 6-carbon moieties or terminal, para-diones on multi-ring structures. 5-carbon moieties with adjacent diones were among the least toxic OPAHs while the toxicity of multi-ring structures with more centralized para-diones varied considerably. 9,10-PHEQ, BEZO, 7,12-B[a]AQ, and XAN exposures increased expression of several oxidative stress related genes and decreased oxygen consumption rate (OCR), a measurement of mitochondrial respiration. Comprehensive in vivo characterization of 38 structurally diverse OPAHs indicated differential AHR dependency and a prominent role for oxidative stress in the toxicity mechanisms. - Highlights: OPAHs are byproducts of combustion present in the environment. OPAHs pose a largely

  5. Tetracationic cyclophanes and their use in the sequestration of polyaromatic hydrocarbons by way of complexation

    DOE Patents [OSTI]

    Stoddart, J. Fraser; Barnes, Jonathan C.; Juri, Michal

    2016-03-22

    Novel tetracationic cyclophanes incorporating .pi.-electron poor organic compounds into their ring structures, as well as methods of making the cyclophanes, are provided. The cyclophanes are able to form electron donor-acceptor complexes with a variety of polyaromatic hydrocarbons (PAHs) ranging in size, shape, and electron density. Also provided are methods of using the cyclophanes in the sequestration of PAHs in liquid or gaseous samples, the separation of PAHs from liquid or gaseous samples, the detection of PAHs in liquid samples, and the exfoliation of graphene via pseudopolyrotaxane formation.

  6. Selective thermal oxidation of hydrocarbons in zeolites by oxygen

    DOE Patents [OSTI]

    Frei, Heinz; Blatter, Fritz; Sun, Hai

    2000-01-01

    A process for selective thermal oxidation of hydrocarbons adsorbed onto zeolite matrices. A highly selective thermal oxidation of unsubstituted or alkyl substituted alkanes, alkenes, aromatics and cycloalkyls is carried out in solvent free zeolites under dark thermal conditions. The process oxidizes hydrocarbons almost completely selectively without substantial production of byproducts.

  7. Selective thermal and photooxidation of hydrocarbons in zeolites by oxygen

    DOE Patents [OSTI]

    Frei, Heinz; Blatter, Fritz; Sun, Hai

    2001-01-01

    A process for a combined selective thermal oxidation and photooxidation of hydrocarbons adsorbed onto zeolite matrices. A highly combined selective thermal oxidation and photooxidation of unsubstituted or alkyl substituted alkanes, alkenes, aromatics and cycloalkyls in solvent free zeolites under dark thermal conditions or under irradiation with visible light. The process oxidizes hydrocarbons almost completely selectively without substantial production of byproducts.

  8. Selective thermal and photooxidation of hydrocarbons in zeolites by oxygen

    DOE Patents [OSTI]

    Frei, H.; Blatter, F.; Sun, H.

    1999-06-22

    A process is described for selective thermal oxidation or photooxidation of hydrocarbons adsorbed onto zeolite matrices. A highly selective thermal oxidation and photooxidation of unsubstituted or alkyl substituted alkanes, alkenes, aromatics and cycloalkyls in solvent free zeolites under dark thermal conditions or under irradiation with visible light. The process oxidizes hydrocarbons almost completely selectively without substantial production of byproducts. 19 figs.

  9. Selective thermal and photooxidation of hydrocarbons in zeolites by oxygen

    DOE Patents [OSTI]

    Frei, Heinz; Blatter, Fritz; Sun, Hai

    1999-01-01

    A process for selective thermal oxidation or photooxidation of hydrocarbons adsorbed onto zeolite matrices. A highly selective thermal oxidation and photooxidation of unsubstituted or alkyl substituted alkanes, alkenes, aromatics and cycloalkyls in solvent free zeolites under dark thermal conditions or under irradiation with visible light. The process oxidizes hydrocarbons almost completely selectively without substantial production of byproducts.

  10. Hydrous pyrolysis/oxidation process for in situ destruction of chlorinated hydrocarbon and fuel hydrocarbon contaminants in water and soil

    DOE Patents [OSTI]

    Knauss, Kevin G.; Copenhaver, Sally C.; Aines, Roger D.

    2000-01-01

    In situ hydrous pyrolysis/oxidation process is useful for in situ degradation of hydrocarbon water and soil contaminants. Fuel hydrocarbons, chlorinated hydrocarbons, polycyclic aromatic hydrocarbons, petroleum distillates and other organic contaminants present in the soil and water are degraded by the process involving hydrous pyrolysis/oxidation into non-toxic products of the degradation. The process uses heat which is distributed through soils and water, optionally combined with oxygen and/or hydrocarbon degradation catalysts, and is particularly useful for remediation of solvent, fuel or other industrially contaminated sites.

  11. Process for conversion of light olefins to LPG and aromatics

    SciTech Connect (OSTI)

    Martindale, D.C.; Andermann, R.E.; Mowry, J.R.

    1989-01-03

    A hydrocarbon conversion process is described which comprises passing a hydrocarbon feed stream comprising at least 30 mole percent olefins having 3 to 4 carbon atoms per molecule and also comprising at least 50 mole percent paraffins having 3 to 4 carbon atoms per molecule and containing less than 10 mole percent C/sub 5/-plus hydrocarbons into a catalytic reaction zone operated at low severity conditions and contacting the feed stream with a solid catalyst gallium. A reaction zone effluent stream is produced comprising C/sub 6/-C/sub 8/ aromatic hydrocarbons and C/sub 3/-C/sub 4/ paraffins, with the reaction zone effluent stream containing less than 10 mole percent olefinic hydrocarbons. The low severity conditions include a combination of pressure, feed space velocity and temperature, including a temperature below 425/sup 0/C, which results in a partial conversion of the feed hydrocarbons into aromatic hydrocarbons whereby: (i) when the effluent is separated there are produced a first product stream, which first product stream is rich in C/sub 6/-C/sub 8/ aromatic hydrocarbons and is withdrawn from the process, with the second product stream, which second product stream is rich in C/sub 3/-C/sub 4/ paraffins and is withdrawn from the process, with the second product stream having a flow rate equal to at least 30 wt. percent of the flow rate of the feed stream; and (ii) the mass flow rate of paraffinic hydrocarbons out of the reaction zone exceeds the mass flow rate of paraffinic hydrocarbons into the reaction zone.

  12. Apparatus for recovering gaseous hydrocarbons from hydrocarbon...

    Office of Scientific and Technical Information (OSTI)

    A method and apparatus are provided for producing gaseous hydrocarbons from formations comprising solid hydrocarbon hydrates located under either a body of land or a body of water. ...

  13. Apparatus for hydrocarbon extraction

    DOE Patents [OSTI]

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  14. 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.

  15. Chlorinated Hydrocarbons

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

    by Satish C. B. Myneni, Department of Geosciences, Princeton University, Princeton, NJ 08544 When we think of chlorine, we often relate it to the salt used in food preparation, chloride in the oceans, chlorine gas from swimming pools, and gaseous chlorofluorocarbons that have close links to the depletion of stratospheric ozone. We rarely think of thousands of chlorinated hydrocarbons that exist in the natural systems, several of which are highly toxic to humans (1). The C-Cl bond, common to all

  16. Process for converting light alkanes to higher hydrocarbons

    DOE Patents [OSTI]

    Noceti, Richard P.; Taylor, Charles E.

    1988-01-01

    A process is disclosed for the production of aromatic-rich, gasoline boiling range hydrocarbons from the lower alkanes, particularly from methane. The process is carried out in two stages. In the first, alkane is reacted with oxygen and hydrogen chloride over an oxyhydrochlorination catalyst such as copper chloride with minor proportions of potassium chloride and rare earth chloride. This produces an intermediate gaseous mixture containing water and chlorinated alkanes. The chlorinated alkanes are contacted with a crystalline aluminosilicate catalyst in the hydrogen or metal promoted form to produce gasoline range hydrocarbons with a high proportion of aromatics and a small percentage of light hydrocarbons (C.sub.2 -C.sub.4). The light hydrocarbons can be recycled for further processing over the oxyhydrochlorination catalyst.

  17. Fundamental spectroscopic studies of carbenes and hydrocarbon radicals

    SciTech Connect (OSTI)

    Gottlieb, C.A.; Thaddeus, P.

    1993-12-01

    Highly reactive carbenes and carbon-chain radicals are studied at millimeter wavelengths by observing their rotational spectra. The purpose is to provide definitive spectroscopic identification, accurate spectroscopic constants in the lowest vibrational states, and reliable structures of the key intermediates in reactions leading to aromatic hydrocarbons and soot particles in combustion.

  18. Draft Genome Sequence of the Polycyclic Aromatic Hydrocarbon...

    Office of Scientific and Technical Information (OSTI)

    Authors: Chauhan, Archana 1 ; Layton, Alice 2 ; Williams, Daniel W 1 ; Smart, Abby E. 2 ; Ripp, Steven Anthony 1 ; Karpinets, Tatiana V 1 ; Brown, Steven D 1 ; ...

  19. Engineered Antibodies for Monitoring of Polynuclear Aromatic Hydrocarbons

    SciTech Connect (OSTI)

    Alexander E. Karu Ph.D; Victoria A. Roberts Ph.D.; Qing X. Li, Ph.D.

    2002-01-17

    This project was undertaken to fill needs in ODE's human and ecosystem health effects research, site remediation, rapid emergency response, and regulatory compliance monitoring programs. Doe has greatly stimulated development and validation of antibody-based, rapid, field-portable detection systems for small hazardous compounds. These range from simple dipsticks, microplate enzyme-linked immunosorbent assays (ELISAs), and hand-held colorimeters, to ultrasensitive microfluidic reactors, fiber-optic sensors and microarrays that can identify multiple analytes from patterns of cross-reactivity. Unfortunately, the technology to produce antibodies with the most desirable properties did not keep pace. Lack of antibodies remains a limiting factor in production and practical use of such devices. The goals of our project were to determine the chemical and structural bases for the antibody-analyte binding interactions using advanced computational chemistry, and to use this information to create useful new binding properties through in vitro genetic engineering and combinatorial library methods.

  20. Synthetic fuel aromaticity and staged combustion

    SciTech Connect (OSTI)

    Longanbach, J. R.; Chan, L. K.; Levy, A.

    1982-11-15

    Samples of middle and heavy SRC-II distillates were distilled into 50 C boiling point range fractions. These were characterized by measurements of their molecular weight, elemental analysis and basic nitrogen content and calculation of average molecular structures. The structures typically consisted of 1 to 3 aromatic rings fused to alicyclic rings with short, 1 to 3 carbon aliphatic side chains. The lower boiling fractions contained significant amounts (1 atom/molecule) of oxygen while the heavier fractions contained so few heteroatoms that they were essentially hydrocarbons. Laboratory scale oxidative-pyrolysis experiments were carried out at pyrolysis temperatures of 500 to 1100 C and oxygen concentrations from 0 to 100 percent of stoichiometry. Analysis of liquid products, collected in condensers cooled with liquid nitrogen showed that aromatization is a major reaction in the absence of oxygen. The oxygen-containing materials (phenolics) seem to be more resistant to thermal pyrolysis than unsubstituted aromatics. Nitrogen converts from basic to nonbasic forms at about 500 C. The nonbasic nitrogen is more stable and survives up to 700 C after which it is slowly removed. A recently constructed 50,000 Btu/hr staged combustor was used to study the chemistry of the nitrogen and aromatics. SRC II combustion was studied under fuel-rich, first-stage conditions at air/fuel ratios from 0.6 to 1.0 times stoichiometric. The chemistry of the fuel during combustion calls for further investigation in order to examine the mechanism by which HCN is evolved as a common intermediate for the formation of the nitrogen-containing gaseous combustion products. 25 references, 45 figures, 25 tables.

  1. Pah Temple Pool & Spa Low Temperature Geothermal Facility | Open...

    Open Energy Info (EERE)

    Facility Facility Pah Temple Sector Geothermal energy Type Pool and Spa Location Hurricane, Utah Coordinates 37.1752607, -113.2899484 Show Map Loading map......

  2. Process for conversion of lignin to reformulated hydrocarbon gasoline

    SciTech Connect (OSTI)

    Shabtai, Joseph S.; Zmierczak, Wlodzimierz W.; Chornet, Esteban

    1999-09-28

    A process for converting lignin into high-quality reformulated hydrocarbon gasoline compositions in high yields is disclosed. The process is a two-stage, catalytic reaction process that produces a reformulated hydrocarbon gasoline product with a controlled amount of aromatics. In the first stage, a lignin material is subjected to a base-catalyzed depolymerization reaction in the presence of a supercritical alcohol as a reaction medium, to thereby produce a depolymerized lignin product. In the second stage, the depolymerized lignin product is subjected to a sequential two-step hydroprocessing reaction to produce a reformulated hydrocarbon gasoline product. In the first hydroprocessing step, the depolymerized lignin is contacted with a hydrodeoxygenation catalyst to produce a hydrodeoxygenated intermediate product. In the second hydroprocessing step, the hydrodeoxygenated intermediate product is contacted with a hydrocracking/ring hydrogenation catalyst to produce the reformulated hydrocarbon gasoline product which includes various desirable naphthenic and paraffinic compounds.

  3. Aromatic molecules as spintronic devices

    SciTech Connect (OSTI)

    Ojeda, J. H.; Orellana, P. A.; Laroze, D.

    2014-03-14

    In this paper, we study the spin-dependent electron transport through aromatic molecular chains attached to two semi-infinite leads. We model this system taking into account different geometrical configurations which are all characterized by a tight binding Hamiltonian. Based on the Green's function approach with a Landauer formalism, we find spin-dependent transport in short aromatic molecules by applying external magnetic fields. Additionally, we find that the magnetoresistance of aromatic molecules can reach different values, which are dependent on the variations in the applied magnetic field, length of the molecules, and the interactions between the contacts and the aromatic molecule.

  4. Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters...

    Office of Environmental Management (EM)

    Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop The Hydrogen, Hydrocarbons, ...

  5. Kidney cancer and hydrocarbon exposures among petroleum refinery workers

    SciTech Connect (OSTI)

    Poole, C.; Dreyer, N.A.; Satterfield, M.H.; Levin, L.

    1993-12-01

    To evaluate the hypothesis of increased kidney cancer risk after exposure to hydrocarbons, especially those present in gasoline, we conducted a case-control study in a cohort of approximately 100,000 male refinery workers from five petroleum companies. A review of 18,323 death certificates identified 102 kidney cancer cases, to each of whom four controls were matched by refinery location and decade of birth. Work histories, containing an average of 15.7 job assignments per subject, were found for 98% of the cases and 94% of the controls. Tb each job, industrial hygienists assigned semiquantitative ratings for the intensity and frequency of exposures to three hydrocarbon categories: nonaromatic liquid gasoline distillates, aromatic hydrocarbons, and the more volatile hydrocarbons. Ratings of {open_quotes}present{close_quotes} or {open_quotes}absent{close_quotes} were assigned for seven additional exposures: higher boiling hydrocarbons, polynuclear aromatic hydrocarbons, asbestos, chlorinated solvents, ionizing radiation, and lead. Each exposure had either no association or a weak association with kidney cancer. For the hydrocarbon category of principal a priori interest, the nonaromatic liquid gasoline distillates, the estimated relative risk (RR) for any exposure above refinery background was 1.0 (95% confidence interval [CI] 0.5-1.9). Analyses of cumulative exposures and of exposures in varying time periods before kidney cancer occurrence also produced null or near-null results. In an analysis of the longest job held by each subject (average duration 9.2 years or 40% of the refiner&y work history), three groups appeared to be at increased risk: laborers (RR = 1.9,95% CI 1.0-3.9); workers in receipt, storage, and movements (RR = 2.5,95% CI 0.9-6.6); and unit cleaners (RR = 2.3, 95% CI 0.5-9.9). 53 refs., 7 tabs.

  6. Recovering hydrocarbons from hydrocarbon-containing vapors

    DOE Patents [OSTI]

    Mirza, Zia I.; Knell, Everett W.; Winter, Bruce L.

    1980-09-30

    Values are recovered from a hydrocarbon-containing vapor by contacting the vapor with quench liquid consisting essentially of hydrocarbons to form a condensate and a vapor residue, the condensate and quench fluid forming a combined liquid stream. The combined liquid stream is mixed with a viscosity-lowering liquid to form a mixed liquid having a viscosity lower than the viscosity of the combined liquid stream to permit easy handling of the combined liquid stream. The quench liquid is a cooled portion of the mixed liquid. Viscosity-lowering liquid is separated from a portion of the mixed liquid and cycled to form additional mixed liquid.

  7. 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.

  8. Hydrocarbons in intertidal sediments and mussels from Prince William Sound, Alaska, 1977-1980: Characterization and probable sources. Technical memo

    SciTech Connect (OSTI)

    Karinen, J.F.; Babcock, M.M.; Brown, D.W.; MacLeod, W.D.; Ramos, L.S.

    1993-01-01

    The oil spill that resulted from the March 1989 grounding of the oil tanker vessel Exxon Valdez provides a unique opportunity for the study of marine oil pollution effects because the spilled crude oil polluted a large geographic area that was previously considered pristine. The only sources of confounding hydrocarbons in the areas of Prince William Sound, Alaska, impacted by the spill are naturally occurring hydrocarbons and anthropogenic hydrocarbons from occasional boating activity in the Sound or due to long-range atmospheric transport. The authors' objectives were to determine the levels, intra-annual variability, and interannual variability of selected alkane hydrocarbons and PAHs in intertidal sediments and in M. trossulus tissues at a network of sampling stations over the 4-year sampling period, and if possible to identify the likely sources of hydrocarbons found.

  9. Plasma Processing Of Hydrocarbon

    SciTech Connect (OSTI)

    Grandy, Jon D; Peter C. Kong; Brent A. Detering; Larry D. Zuck

    2007-05-01

    The Idaho National Laboratory (INL) developed several patented plasma technologies for hydrocarbon processing. The INL patents include nonthermal and thermal plasma technologies for direct natural gas to liquid conversion, upgrading low value heavy oil to synthetic light crude, and to convert refinery bottom heavy streams directly to transportation fuel products. Proof of concepts has been demonstrated with bench scale plasma processes and systems to convert heavy and light hydrocarbons to higher market value products. This paper provides an overview of three selected INL patented plasma technologies for hydrocarbon conversion or upgrade.

  10. Hydroprocessing hydrocarbon oils

    SciTech Connect (OSTI)

    Simpson, H.D.; Borgens, P.B.

    1990-07-10

    This patent describes a catalytic hydroprocess of a hydrocarbon oil containing nitrogen or sulfur. It comprises: contacting a catalytic composition with the hydrocarbon oil under hydroprocessing conditions so as to produce a product hydrocarbon oil containing less nitrogen or sulfur than the hydrocarbon oil, the catalytic composition prepared by the method comprising the steps of impregnating porous refractory support particles with an aqueous impregnating solution comprising one or more Group VIB metal components, one or more phosphorus components and citric acid, the citric acid in a mole ratio to the Group VIB metal components calculated as the Group VIB metal trioxide of less than 1 to 1. The solution has a pH less than 1.0 and calcining the impregnated support particles to produce a catalytic composition containing a Group VIB metal component and a phosphorous component on the porous refractory oxide support.

  11. Membrane separation of hydrocarbons

    DOE Patents [OSTI]

    Funk, Edward W.; Kulkarni, Sudhir S.; Chang, Y. Alice

    1986-01-01

    Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture over a polymeric membrane which comprises a polymer capable of maintaining its integrity in the presence of hydrocarbon compounds at temperature ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psi. The membranes which possess pore sizes ranging from about 10 to about 500 Angstroms are cast from a solvent solution and recovered.

  12. Hydrocarbon geoscience research strategy

    SciTech Connect (OSTI)

    Not Available

    1990-04-01

    This document outlines a strategy for oil and gas related research focused on optimizing the economic producibility of the Nation's resources. The Hydrocarbon Geoscience Strategy was developed by the Hydrocarbon Geoscience Research Coordinating Committee of the Department of Energy (DOE). This strategy forms the basis for the development of DOE Fossil Energy's Oil Research Program Implementation Plan and Natural Gas Program Implementation Plan. 24 refs., 5 figs., 3 tabs.

  13. Detection of chlorinated aromatic compounds

    DOE Patents [OSTI]

    Ekechukwu, A.A.

    1996-02-06

    A method for making a composition for measuring the concentration of chlorinated aromatic compounds in aqueous fluids, and an optical probe for use with the method are disclosed. The composition comprises a hydrophobic polymer matrix, preferably polyamide, with a fluorescent indicator uniformly dispersed therein. The indicator fluoresces in the presence of the chlorinated aromatic compounds with an intensity dependent on the concentration of these compounds in the fluid of interest, such as 8-amino-2-naphthalene sulfonate. The probe includes a hollow cylindrical housing that contains the composition in its distal end. The probe admits an aqueous fluid to the probe interior for exposure to the composition. An optical fiber transmits excitation light from a remote source to the composition while the indicator reacts with chlorinated aromatic compounds present in the fluid. The resulting fluorescence light signal is reflected to a second optical fiber that transmits the light to a spectrophotometer for analysis. 5 figs.

  14. Detection of chlorinated aromatic compounds

    DOE Patents [OSTI]

    Ekechukwu, Amy A.

    1996-01-01

    A method for making a composition for measuring the concentration of chloated aromatic compounds in aqueous fluids, and an optical probe for use with the method. The composition comprises a hydrophobic polymer matrix, preferably polyamide, with a fluorescent indicator uniformly dispersed therein. The indicator fluoresces in the presence of the chlorinated aromatic compounds with an intensity dependent on the concentration of these compounds in the fluid of interest, such as 8-amino-2-naphthalene sulfonate. The probe includes a hollow cylindrical housing that contains the composition in its distal end. The probe admits an aqueous fluid to the probe interior for exposure to the composition. An optical fiber transmits excitation light from a remote source to the composition while the indicator reacts with chlorinated aromatic compounds present in the fluid. The resulting fluorescence light signal is reflected to a second optical fiber that transmits the light to a spectrophotometer for analysis.

  15. 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 analysismass 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 (450600 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 DielsAlder condensation (e.g., two furans form benzofuran and water), decarbonylation (e

  16. Hydrocarbon Technologies | Open Energy Information

    Open Energy Info (EERE)

    Technologies Jump to: navigation, search Name: Hydrocarbon Technologies Place: Lawrenceville, New Jersey Zip: 8648 Sector: Efficiency Product: String representation...

  17. Dispersant solutions for dispersing hydrocarbons

    DOE Patents [OSTI]

    Tyndall, R.L.

    1997-03-11

    A dispersant solution includes a hydrocarbon dispersing solution derived from a bacterium from ATCC 75527, ATCC 75529, or ATCC 55638.

  18. Dispersant solutions for dispersing hydrocarbons

    DOE Patents [OSTI]

    Tyndall, Richard L. (Clinton, TN)

    1997-01-01

    A dispersant solution includes a hydrocarbon dispersing solution derived from a bacterium from ATCC 75527, ATCC 75529, or ATCC 55638.

  19. Optrode for sensing hydrocarbons

    DOE Patents [OSTI]

    Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

    1987-05-19

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons. 6 figs.

  20. Optrode for sensing hydrocarbons

    DOE Patents [OSTI]

    Miller, H.; Milanovich, F.P.; Hirschfeld, T.B.; Miller, F.S.

    1988-09-13

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons. 5 figs.

  1. Optrode for sensing hydrocarbons

    DOE Patents [OSTI]

    Miller, Holly (Bethel Island, CA); Milanovich, Fred P. (Lafayette, CA); Hirschfeld, Tomas B. (Livermore, CA); Miller, Fred S. (Bethel Island, CA)

    1987-01-01

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons.

  2. Optrode for sensing hydrocarbons

    DOE Patents [OSTI]

    Miller, Holly (Bethel Island, CA); Milanovich, Fred P. (Lafayette, CA); Hirschfeld, Tomas B. (Livermore, CA); Miller, Fred S. (Bethel Island, CA)

    1988-01-01

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons.

  3. Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop: Agenda and Objectives Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop:...

  4. Conversion of heavy hydrocarbon oils

    SciTech Connect (OSTI)

    Chen, N.Y.; Pelrine, B.P.; Yan, T.Y.

    1982-12-14

    This invention provides a process for upgrading a heavy hydrocarbon oil to motor fuel products. The heavy hydrocarbon oil is admixed with a metal halide catalyst and a solvent component under supercritical conditions to form (1) a dense-gas solvent phase which contains refined hydrocarbon crackate, and which is substantially free of metal halide catalyst content; and (2) a residual asphaltic phase.

  5. Hydrocarbonization research: completion report

    SciTech Connect (OSTI)

    Youngblood, E.L.; Cochran, H.D. Jr.; Westmoreland, P.R.; Brown, C.H. Jr.; Oswald, G.E.; Barker, R.E.

    1981-01-01

    Hydrocarbonization is a relatively simple process used for producing oil, substitute natural gas, and char by heating coal under a hydrogen-rich atmosphere. This report describes studies that were performed in a bench-scale hydrocarbonization system at Oak Ridge National Laboratory (ORNL) during the period 1975 to 1978. The results of mock-up studies, coal metering valve and flowmeter development, and supporting work in an atmospheric hydrocarbonization system are also described. Oil, gas, and char yields were determined by hydrocarbonization of coal in a 0.1-m-diam fluidized-bed reactor operated at a pressure of 2170 kPa and at temperatures ranging from 694 to 854 K. The nominal coal feed rate was 4.5 kg/h. Wyodak subbituminous coal was used for most of the experiments. A maximum oil yield of approx. 21% based on moisture- and ash-free (maf) coal was achieved in the temperature range of 810 to 840 K. Recirculating fluidized-bed, uniformly fluidized-bed, and rapid hydropyrolysis reactors were used. A series of operability tests was made with Illinois No. 6 coal to determine whether caking coal could be processed in the recirculating fluidized-bed reactor. These tests were generally unsuccessful because of agglomeration and caking problems; however, these problems were eliminated by the use of chemically pretreated coal. Hydrocarbonization experiments were carried out with Illinois No. 6 coal that had been pretreated with CaO-NaOH, Na/sub 2/CO/sub 3/, and CaO-Na/sub 2/CO/sub 3/. Oil yields of 14, 24, and 21%, respectively, were obtained from the runs with treated coal. Gas and char yield data and the composition of the oil, gas, and char products are presented.

  6. Apparatus and methods for hydrocarbon extraction

    DOE Patents [OSTI]

    Bohnert, George W.; Verhulst, Galen G.

    2016-04-26

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  7. Catalysts and process for liquid hydrocarbon fuel production

    DOE Patents [OSTI]

    White, Mark G; Liu, Shetian

    2014-12-09

    The present invention provides a novel process and system in which a mixture of carbon monoxide and hydrogen synthesis gas, or syngas, is converted into hydrocarbon mixtures composed of high quality gasoline components, aromatic compounds, and lower molecular weight gaseous olefins in one reactor or step. The invention utilizes a novel molybdenum-zeolite catalyst in high pressure hydrogen for conversion, as well as a novel rhenium-zeolite catalyst in place of the molybdenum-zeolite catalyst, and provides for use of the novel catalysts in the process and system of the invention.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Nucleophilic fluorination of aromatic compounds

    DOE Patents [OSTI]

    Satyamurthy, Nagichettiar; Barrio, Jorge R

    2014-03-18

    Iodylbenzene derivatives substituted with electron donating as well as electron withdrawing groups on the aromatic ring are used as precursors in aromatic nucleophilic substitution reactions. The iodyl group (IO.sub.2) is regiospecifically substituted by nucleophilic fluoride to provide the corresponding fluoroaryl derivatives. No-carrier-added [F-18]fluoride ion derived from anhydrous [F-18](F/Kryptofix, [F-18]CsF or a quaternary ammonium fluoride (e.g., Me.sub.4NF, Et.sub.4NF, n-Bu.sub.4NF, (PhCH.sub.2).sub.4NF) exclusively substitutes the iodyl moiety in these derivatives and provides high specific activity F-18 labeled fluoroaryl analogs. Iodyl derivatives of a benzothiazole analog and 6-iodyl-L-dopa derivatives have been synthesized as precursors and have been used in the preparation of no-carrier-added [F-18]fluorobenzothiazole as well as 6-[F-18]fluoro-L-dopa.

  13. 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.

  14. 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.

  15. Membrane separation of hydrocarbons

    DOE Patents [OSTI]

    Chang, Y. Alice; Kulkarni, Sudhir S.; Funk, Edward W.

    1986-01-01

    Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture through a polymeric membrane. The membrane which is utilized to effect the separation comprises a polymer which is capable of maintaining its integrity in the presence of hydrocarbon compounds and which has been modified by being subjected to the action of a sulfonating agent. Sulfonating agents which may be employed will include fuming sulfuric acid, chlorosulfonic acid, sulfur trioxide, etc., the surface or bulk modified polymer will contain a degree of sulfonation ranging from about 15 to about 50%. The separation process is effected at temperatures ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psig.

  16. Hydrocarbons from methanol

    SciTech Connect (OSTI)

    Chang, C.D.

    1983-01-01

    During the early 1970s, the conversion of methanol to hydrocarbons emerged as a viable industrial process due to two events: the discovery by workers at Mobil Oil Company of the selective catalytic conversion of methanol to high octane gasoline over zeolite catalysts and the 1973 Arab oil embargo. This survey attempts to comprehensively cover the journal literature and selectively cover the patent literature dealing with the theoretical aspects of the methanol conversion. 178 references. (BLM)

  17. Direct hydrocarbon fuel cells

    DOE Patents [OSTI]

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  18. Radical scavengers from heavy hydrocarbons

    SciTech Connect (OSTI)

    Kubo, Junichi

    1996-10-01

    The hydrogen-donating properties of some hydrocarbons form the basis for processes such as coal liquefaction and heavy oil upgrading. However, these hydrocarbons have seldom been used for other purposes, because their potential applications have not been well recognized. Research has indicated that these hydrogen-donating hydrocarbons can be used in important reactions as radical scavengers and have properties particular to those of pure hydrocarbons without functional groups containing heteroatoms. Over years of study researchers have found that pure hydrocarbons with radical-scavenging effects nearly as high as those in conventional hindered phenolic antioxidants can be produced from petroleum, and these hydrogen-donating hydrocarbons exhibit such effects even in oxidative atmospheres (i.e., they function as antioxidants). He has also shown that these mixtures have some properties particular to pure hydrocarbons without functional groups containing heteroatoms, and they`ve seen that a mechanism based on the steric effects appears when these hydrocarbons are used in heavy oil hydroprocessing. Hydrogen-donating hydrocarbons should be a viable resource in many applications. In this article, he presents radical-scavenging abilities, characteristics as pure hydrocarbons, and applications on the basis of the studies.

  19. Process and catalyst for converting synthesis gas to liquid hydrocarbon mixture

    DOE Patents [OSTI]

    Rao, V. Udaya S.; Gormley, Robert J.

    1987-01-01

    Synthesis gas containing CO and H.sub.2 is converted to a high-octane hydrocarbon liquid in the gasoline boiling point range by bringing the gas into contact with a heterogeneous catalyst including, in physical mixture, a zeolite molecular sieve, cobalt at 6-20% by weight, and thoria at 0.5-3.9% by weight. The contacting occurs at a temperature of 250.degree.-300.degree. C., and a pressure of 10-30 atmospheres. The conditions can be selected to form a major portion of the hydrocarbon product in the gasoline boiling range with a research octane of more than 80 and less than 10% by weight aromatics.

  20. Noncomparative scaling of aromaticity through electron itinerancy

    SciTech Connect (OSTI)

    Paul, Satadal; Goswami, Tamal; Misra, Anirban

    2015-10-15

    Aromaticity is a multidimensional concept and not a directly observable. These facts have always stood in the way of developing an appropriate theoretical framework for scaling of aromaticity. In the present work, a quantitative account of aromaticity is developed on the basis of cyclic delocalization of π-electrons, which is the phenomenon leading to unique features of aromatic molecules. The stabilization in molecular energy, caused by delocalization of π-electrons is obtained as a second order perturbation energy for archetypal aromatic systems. The final expression parameterizes the aromatic stabilization energy in terms of atom to atom charge transfer integral, onsite repulsion energy and the population of spin orbitals at each site in the delocalized π-electrons. An appropriate computational platform is framed to compute each and individual parameter in the derived equation. The numerical values of aromatic stabilization energies obtained for various aromatic molecules are found to be in close agreement with available theoretical and experimental reports. Thus the reliable estimate of aromaticity through the proposed formalism renders it as a useful tool for the direct assessment of aromaticity, which has been a long standing problem in chemistry.

  1. IRS SCAN-MAPPING OF THE WASP-WAIST NEBULA (IRAS 16253-2429). I. DERIVATION OF SHOCK CONDITIONS FROM H{sub 2} EMISSION AND DISCOVERY OF 11.3 {mu}m PAH ABSORPTION

    SciTech Connect (OSTI)

    Barsony, Mary; Wolf-Chase, Grace A.; Ciardi, David R.

    2010-09-01

    The outflow driven by the Class 0 protostar, IRAS 16253-2429, is associated with bipolar cavities visible in scattered mid-infrared light, which we refer to as the Wasp-Waist Nebula. InfraRed Spectometer (IRS) scan mapping with the Spitzer Space Telescope of a {approx}1' x 2' area centered on the protostar was carried out. The outflow is imaged in six pure rotational (0-0 S(2) through 0-0 S(7)) H{sub 2} lines, revealing a distinct, S-shaped morphology in all maps. A source map in the 11.3 {mu}m polycyclic aromatic hydrocarbon (PAH) feature is presented in which the protostellar envelope appears in absorption. This is the first detection of absorption in the 11.3 {mu}m PAH feature. Spatially resolved excitation analysis of positions in the blue- and redshifted outflow lobes, with extinction-corrections determined from archival Spitzer 8 {mu}m imaging, shows remarkably constant temperatures of {approx}1000 K in the shocked gas. The radiated luminosity in the observed H{sub 2} transitions is found to be 1.94 {+-} 0.05 x 10{sup -5} L{sub sun} in the redshifted lobe and 1.86 {+-} 0.04 x 10{sup -5} L{sub sun} in the blueshifted lobe. These values are comparable to the mechanical luminosity of the flow. By contrast, the mass of hot (T {approx} 1000 K) H{sub 2} gas is 7.95 {+-} 0.19 x 10{sup -7} M{sub sun} in the redshifted lobe and 5.78 {+-} 0.17 x 10{sup -7} M{sub sun} in the blueshifted lobe. This is just a tiny fraction, of order 10{sup -3}, of the gas in the cold (30 K), swept-up gas mass derived from millimeter CO observations. The H{sub 2} ortho/para ratio of 3:1 found at all mapped points in this flow suggests previous passages of shocks through the gas. Comparison of the H{sub 2} data with detailed shock models of Wilgenbus et al. shows the emitting gas is passing through Jump (J-type) shocks. Pre-shock densities of 10{sup 4} cm{sup -3{<=}} n {sub H{<=}} 10{sup 5} cm{sup -3} are inferred for the redshifted lobe and n {sub H{<=}} 10{sup 3} cm{sup -3} for the

  2. Quantum transport through aromatic molecules

    SciTech Connect (OSTI)

    Ojeda, J. H.; Rey-Gonzlez, R. R.; Laroze, D.

    2013-12-07

    In this paper, we study the electronic transport properties through aromatic molecules connected to two semi-infinite leads. The molecules are in different geometrical configurations including arrays. Using a nearest neighbor tight-binding approach, the transport properties are analyzed into a Green's function technique within a real-space renormalization scheme. We calculate the transmission probability and the Current-Voltage characteristics as a function of a molecule-leads coupling parameter. Our results show different transport regimes for these systems, exhibiting metal-semiconductor-insulator transitions and the possibility to employ them in molecular devices.

  3. Aromatics and phenols from catalytic pyrolysis of Douglas fir pellets in microwave with ZSM-5 as a catalyst

    SciTech Connect (OSTI)

    Wang, Lu; Lei, Hanwu; Ren, Shoujie; Bu, Quan; Liang, Jing; Wei, Yi; Liu, Yupeng; Lee, Guo-Shuh J.; Chen, Shulin; Tang, Juming; Zhang, Qin; Ruan, Roger

    2012-11-04

    Microwave assisted catalytic pyrolysis was investigated to convert Douglas fir pellets to bio-oils by a ZSM-5 Zeolite catalyst. A central composite experimental design (CCD) was used to optimize the catalytic pyrolysis process. The effects of reaction time, temperature and catalyst to biomass ratio on the bio-oil, syngas, and biochar yields were determined. GC/MS analysis results showed that the bio-oil contained a series of important and useful chemical compounds. Phenols, guaiacols, and aromatic hydrocarbons were the most abundant compounds which were about 50-82 % in bio-oil depending on the pyrolysis conditions. Comparison between the bio-oils from microwave pyrolysis with and without catalyst showed that the catalyst increased the content of aromatic hydrocarbons and phenols. A reaction pathway was proposed for microwave assisted catalyst pyrolysis of Douglas fir pellets.

  4. Dehydrocyclodimerization, converting LPG to aromatics

    SciTech Connect (OSTI)

    Johnson, J.A.; Hilder, G.K.

    1984-03-01

    British Petroleum (BP) recognized the potential need for ways of exploiting feedstocks with low opportunity cost and commenced a research program at its Sunbury Research Center to discover and develop a catalyst for the conversion of LPG to a liquid product. The successful outcome of this research program is the Cyclar /SUP SM/ process, a joint development of UOP Process Division and British Petroleum. The Cyclar process offers a single-step conversion of LPG to an aromatic product which has a highvalue, is easily transported and useful both to fuel and petrochemical applications. The LPG producer can invest in a single unit, avoiding the need to identify and develop markets for multiple C/sub 3/ and C/sub 4/ products. This catalytic process, which employs UOP Continuous Catalyst Regeneration (CCR) technology, can also be applied to refinery light ends to produce a high-quality gasoline. Aromatic and hydrogen yields from propane and butane feeds surpass those obtained from catalytic reforming of Light Arabian naphtha. This paper describes the principles of the Cyclar process and illustrates yields and economics for several interesting applications.

  5. Plasma-Hydrocarbon conversion - Energy Innovation Portal

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

    Hydrocarbon conversion Idaho National Laboratory Contact INL About This Technology Technology Marketing Summary INL's Plasma-Hydrocarbon Conversion process enables conversion of heavy hydrocarbons, such as heavy crude oil and hydrocarbon gases like natural gas, into lighter hydrocarbon materials (e.g. synthetic light oil). Description It can convert hydrocarbon gases to liquid fuels/chemicals. The dielectric barrier discharge plasma process that adds carbon and hydrogen simultaneously to heavy

  6. Hydrocarbon sensors and materials therefor

    DOE Patents [OSTI]

    Pham, Ai Quoc; Glass, Robert S.

    2000-01-01

    An electrochemical hydrocarbon sensor and materials for use in sensors. A suitable proton conducting electrolyte and catalytic materials have been found for specific application in the detection and measurement of non-methane hydrocarbons. The sensor comprises a proton conducting electrolyte sandwiched between two electrodes. At least one of the electrodes is covered with a hydrocarbon decomposition catalyst. Two different modes of operation for the hydrocarbon sensors can be used: equilibrium versus non-equilibrium measurements and differential catalytic. The sensor has particular application for on-board monitoring of automobile exhaust gases to evaluate the performance of catalytic converters. In addition, the sensor can be utilized in monitoring any process where hydrocarbons are exhausted, for instance, industrial power plants. The sensor is low cost, rugged, sensitive, simple to fabricate, miniature, and does not suffer cross sensitivities.

  7. Predicting Electrochemical Windows of Nitrogen Containing Aromatic

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

    Molecules - Joint Center for Energy Storage Research October 20, 2014, Research Highlights Predicting Electrochemical Windows of Nitrogen Containing Aromatic Molecules Various nitrogen containing aromatic base molecules and a descriptive relationship derived to predict their reduction potentials is shown. Scientific Achievement A descriptive relationship is derived for computing reduction potentials of quinoxaline derivatives from the orbital energies of the neutral molecules without

  8. Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters...

    Broader source: Energy.gov (indexed) [DOE]

    Office jointly sponsored a workshop on Hydrogen, Hydrocarbons, and Bioproduct Precursors ... and other techniques to produce hydrogen and higher hydrocarbons (containing ...

  9. Thermocatalytic process for CO.sub.2-free production of hydrogen and carbon from hydrocarbons

    DOE Patents [OSTI]

    Muradov, Nazim Z.

    2011-08-23

    A novel process and apparatus are disclosed for sustainable CO.sub.2-free production of hydrogen and carbon by thermocatalytic decomposition (dissociation, pyrolysis, cracking) of hydrocarbon fuels over carbon-based catalysts in the absence of air and/or water. The apparatus and thermocatalytic process improve the activity and stability of carbon catalysts during the thermocatalytic process and produce both high purity hydrogen (at least, 99.0 volume %) and carbon, from any hydrocarbon fuel, including sulfurous fuels. In a preferred embodiment, production of hydrogen and carbon is achieved by both internal and external activation of carbon catalysts. Internal activation of carbon catalyst is accomplished by recycling of hydrogen-depleted gas containing unsaturated and aromatic hydrocarbons back to the reactor. External activation of the catalyst can be achieved via surface gasification with hot combustion gases during catalyst heating. The process and apparatus can be conveniently integrated with any type of fuel cell to generate electricity.

  10. 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.

  11. 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.

  12. Use of thermal desorption/gas chromatography as a performance-based screening method for petroleum hydrocarbons

    SciTech Connect (OSTI)

    Slavin, P.J. |; Crandall, K.; Dawson, L.; Kottenstette, R.; Wade, M. |

    1996-08-01

    Thermal desorption/gas chromatography (TD/GC) was used to screen soil samples on site for total petroleum hydrocarbon (TPH) content during a RCRA Facility Investigation (RFI). It proved to be a rapid, cost- effective tool for detecting non-aromatic mineral oil in soil. The on- site TD/GC results correlated well with those generated at an off- site laboratory for samples analyzed in accordance with EPA Method 418.1.

  13. Density and viscosity for mixtures of propanoic acid with aromatic hydrocarbons at 298.15 K

    SciTech Connect (OSTI)

    Singh, M.; Gupta, P.C.; Kesharwani, R.N.

    1995-03-01

    The density and viscosity of binary mixtures of propanic acid + benzene, + toluene, and + o-, + m-, and + p-xylenes have been measured at 298.15 K. Excess volumes have been calculated. The interactions existing between the components have been discussed. The results are used to theoretically justify the validity of the viscosity models.

  14. Enrichment of light hydrocarbon mixture

    DOE Patents [OSTI]

    Yang, Dali; Devlin, David; Barbero, Robert S.; Carrera, Martin E.; Colling, Craig W.

    2011-11-29

    Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

  15. Enrichment of light hydrocarbon mixture

    DOE Patents [OSTI]

    Yang; Dali; Devlin, David; Barbero, Robert S.; Carrera, Martin E.; Colling, Craig W.

    2010-08-10

    Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

  16. 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.

  17. Biological enhancement of hydrocarbon extraction

    DOE Patents [OSTI]

    Brigmon, Robin L.; Berry, Christopher J.

    2009-01-06

    A method of microbial enhanced oil recovery for recovering oil from an oil-bearing rock formation is provided. The methodology uses a consortium of bacteria including a mixture of surfactant producing bacteria and non-surfactant enzyme producing bacteria which may release hydrocarbons from bitumen containing sands. The described bioprocess can work with existing petroleum recovery protocols. The consortium microorganisms are also useful for treatment of above oil sands, ground waste tailings, subsurface oil recovery, and similar materials to enhance remediation and/or recovery of additional hydrocarbons from the materials.

  18. Method for producing viscous hydrocarbons

    DOE Patents [OSTI]

    Poston, Robert S. (Winter Park, FL)

    1982-01-01

    A method for recovering viscous hydrocarbons and synthetic fuels from a subterranean formation by drilling a well bore through the formation and completing the well by cementing a casing means in the upper part of the pay zone. The well is completed as an open hole completion and a superheated thermal vapor stream comprised of steam and combustion gases is injected into the lower part of the pay zone. The combustion gases migrate to the top of the pay zone and form a gas cap which provides formation pressure to produce the viscous hydrocarbons and synthetic fuels.

  19. Effect of torrefaction on biomass structure and hydrocarbon production from fast pyrolysis

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

    Neupane, Sneha; Adhikari, Sushil; Wang, Zhouhong; Ragauskas, Arthur; Pu, Yunqiao

    2015-01-27

    Torrefaction has been shown to improve the chemical composition of bio-oils produced from fast pyrolysis by lowering its oxygen content and enhancing the aromatic yield. A Py-GC/MS study was employed to investigate the effect of torrefaction temperatures (225, 250 and 275 °C) and residence times (15, 30 and 45 min) on product distribution from non-catalytic and H+ZSM-5 catalyzed pyrolysis of pinewood. During torrefaction, structural transformations in biomass constitutive polymers: hemicellulose, cellulose and lignin took place, which were evaluated using component analysis, solid state CP/MAS 13C NMR and XRD techniques. Torrefaction caused deacetylation and decomposition of hemicellulose, cleavage of aryl ethermore » linkages and demethoxylation of lignin, degradation of cellulose and an overall increase in aromaticity of biomass, all of which affected the product yield from pyrolysis of torrefied biomass. For non-catalytic pyrolysis, selectivity of phenolic compounds increased with an increase in torrefaction severity while that of furan compounds decreased. In the case of catalytic pyrolysis, the sample torrefied at 225 °C-30 min and 250 °C-15 min resulted in a significant increase in aromatic hydrocarbon (HC) and also total carbon yield (approx. 1.6 times higher) as compared to catalytic pyrolysis of non-torrefied pine. Cleavage of aryl ether linkages and demethoxylation in lignin due to torrefaction caused increased yield of phenolic compounds, which in the presence of a catalyst were dehydrated to form aromatic HC.« less

  20. The effect of the nature of a modifying additive (Pt, Zn, Ga) on the activity of oxide and zeolite catalysts in ethane dehydrogenation and aromatization

    SciTech Connect (OSTI)

    Vasina, T.V.; Masloboyshchikova, O.V.; Chetina, O.V.

    1994-10-01

    The catalytic properties of Pt, Zn, and Ga deposited on supports of various natures (Al{sub 2}O{sub 3}, SiO{sub 2}, NaZSM, and HZSM) in the dehydrogenation and aromatization of ethane were investigated. Pt-containing catalysts are the most active in the conversion of ethane: the selectivity with respect to ethylene is 25-87% depending on the nature of the support. In the presence of Zn- and Ga-containing catalysts the yield of ethylene is 2-3 times lower than with Pt-catalysts. With HZSM modified by Pt, Zn, or Ga aromatic hydrocarbons (ArH) and methane are the main products of ethane transformation. Ga/HZSM is the most efficient catalyst of the aromatization of ethane under the conditions studied (550 {degrees}C, 120 h{sup -1}).

  1. Catalytic hydroprocessing of chlorinated hydrocarbons

    SciTech Connect (OSTI)

    Allen, D.T.

    1996-12-31

    Catalytic hydroprocessing is a promising technology for the treatment or recycling of chlorinated organic waste streams. This paper will describe the hydroprocessing kinetics and reaction pathways of chlorinated aromatics and aliphatics. The compounds investigated include chlorinated benzenes, chlorinated phenols, chlorinated pyridinols, perchloroethylene, trichloroethyene, and dichloroethylenes. Experiments were performed over a NiMo/Al{sub 2}O{sub 3} catalyst in the temperature range of 175{degrees}C to 350{degrees}C. For the chlorinated benzenes, removal of chlorine proceeded at comparable rates for all species from hexachlorobenzene to chlorobenzene. For the chlorophenols and chloropyridinols, dechlorination proceeded at a much higher rate than deoxygenation. Rates of dechlorination of aliphatics were approximately an order of magnitude faster than the rates for aromatics. 10 refs., 4 figs., 1 tab.

  2. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    DOE Patents [OSTI]

    Smith, Robert E. [557 Escondido Cir., Livermore, CA 94550; Dolbeare, Frank A. [5178 Diane La., Livermore, CA 94550

    1980-10-21

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes.

  3. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    DOE Patents [OSTI]

    Smith, Robert E.; Dolbeare, Frank A.

    1979-01-01

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 5-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes.

  4. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    DOE Patents [OSTI]

    Smith, R.E.; Dolbeare, F.A.

    1980-10-21

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes. No Drawings

  5. Biological Conversion of Sugars To Hydrocarbons | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    To Hydrocarbons Biological Conversion of Sugars To Hydrocarbons PDF explaining the biological process of bioenergy Biological Conversion of Sugars To Hydrocarbons (190.69 KB) More Documents & Publications Catalytic Upgrading Sugars To Hydrocarbons Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway Biological Conversion of Sugars to Hydrocarbons Technology Pathway

  6. Prediction of retention and identification of non-substituted polyaromatic hydrocarbons by liquid chromatography

    SciTech Connect (OSTI)

    Lanin, S.N.; Nikitin, Yu.S.

    1988-03-10

    Elucidation of the correlation between the structures of investigated compounds and their retention parameters in liquid chromatography allows one to predict their behavior in the chromatographic system and to choose optimal conditions of resolution, which is the main task. The important and complex problem remains analysis of waste water. Polycyclic aromatic hydrocarbons are among the most widespread and toxic pollutants of industrial waste and natural waters. Many of them are carcinogens. A correlation equation, universal for a certain class of substances, is proposed to describe the retention and separation of polyaromatic hydrocarbons by reversed phase liquid chromatography. The possibility was shown of its application to prediction of retention data for test substances and for their identification.

  7. Soot formation in methane/air nonpremixed flames doped with small quantities of C3 hydrocarbons

    SciTech Connect (OSTI)

    McEnally, C.S.; Pfefferle, L.D.

    1998-03-01

    Gas temperature, C1 to C12 stable hydrocarbon concentrations, and soot volume fractions were measured in an axisymmetry methane/air coflowing nonpremixed flame whose fuel was doped with one mole per cent allene, propene, and propane. The additives did not significantly alter the temperature field, methane mole fractions, or chain-carrying radical concentrations. However, soot volume fractions were increased, in the order allene > propene > propane. The hydrocarbon species measurements indicated that soot formation increases because the additives undergo reaction sequences that raise the concentrations of the benzene and phenyl radical precursors C{sub 3}H{sub 3}, C{sub 4}H{sub 3}, and C{sub 4}H{sub 5}, and consequently enhance the benzene/phenyl formation rate. Therefore, creation of these precursors and of the first aromatic ring are crucial rate-limiting soot formation steps in methane flames.

  8. Syngas Upgrading to Hydrocarbon Fuels Technology Pathway

    SciTech Connect (OSTI)

    Talmadge, M.; Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01

    This technology pathway case investigates the upgrading of woody biomass derived synthesis gas (syngas) to hydrocarbon biofuels. While this specific discussion focuses on the conversion of syngas via a methanol intermediate to hydrocarbon blendstocks, there are a number of alternative conversion routes for production of hydrocarbons through a wide array of intermediates from syngas. Future work will also consider the variations to this pathway to determine the most economically viable and lowest risk conversion route. Technical barriers and key research needs have been identified that should be pursued for the syngas-to-hydrocarbon pathway to be competitive with petroleum-derived gasoline-, diesel- and jet-range hydrocarbon blendstocks.

  9. RECOVERY OF URANIUM BY AROMATIC DITHIOCARBAMATE COMPLEXING

    DOE Patents [OSTI]

    Neville, O.K.

    1959-08-11

    A selective complexing organic solvent extraction process is presented for the separation of uranium values from an aqueous nitric acid solution of neutron irradiated thorium. The process comprises contacting the solution with an organic aromatic dithiccarbamaie and recovering the resulting urancdithiccarbamate complex with an organic solvent such as ethyl acetate.

  10. Temporal trends in and influence of wind on PAH concentrations measured near the Great Lakes

    SciTech Connect (OSTI)

    Cortes, D.R.; Basu, I.; Sweet, C.W.; Hites, R.A.

    2000-02-01

    This paper reports on temporal trends in gas- and particle-phase PAH concentrations measured at three sites in the Great Lakes' Integrated Atmospheric Deposition Network: Eagle Harbor, near Lake Superior, Sleeping Bear Dunes, near Lake Michigan, and Sturgeon Point, near Lake Erie. While gas-phase concentrations have been decreasing since 1991 at all sites, particle-phase concentrations have been decreasing only at Sleeping Bear Dunes. To determine whether these results represent trends in background levels or regional emissions, the average concentrations are compared to those found in urban and rural studies. In addition, the influence of local wind direction on PAH concentrations is investigated, with the assumption that dependence on wind direction implies regional sources. Using these two methods, it is found that PAH concentrations at Eagle Harbor and Sleeping Bear Dunes represent regional background levels but that PAH from the Buffalo Region intrude on the background levels measured at the Sturgeon Point site. At this site, wind from over Lake Erie reduces local PAH concentrations.

  11. Dry reforming of hydrocarbon feedstocks

    SciTech Connect (OSTI)

    Shah, Yatish T.; Gardner, Todd H.

    2014-09-25

    Developments in catalyst technology for the dry reforming of hydrocarbon feedstocks are reviewed for methane, higher hydrocarbons and alcohols. Thermodynamics, mechanisms and the kinetics of dry reforming are also reviewed. The literature on Ni catalysts, bi-metallic Ni catalysts and the role of promoters on Ni catalysts is critically evaluated. The use of noble and transitional metal catalysts for dry reforming is discussed. The application of solid oxide and metal carbide catalysts to dry reforming is also evaluated. Finally, various mechanisms for catalyst deactivation are assessed. This review also examines the various process related issues associated with dry reforming such as its application and heat optimization. Novel approaches such as supercritical dry reforming and microwave assisted dry reforming are briefly expanded upon.

  12. Catalytic method for synthesizing hydrocarbons

    DOE Patents [OSTI]

    Sapienza, Richard S.; Sansone, Michael J.; Slegeir, William A. R.

    1984-01-01

    A method for synthesizing hydrocarbons from carbon monoxide and hydrogen by contacting said gases with a slurry of a catalyst composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants.

  13. Catalytic method for synthesizing hydrocarbons

    DOE Patents [OSTI]

    Sapienza, R.S.; Sansone, M.J.; Slegeir, W.A.R.

    A method for synthesizing hydrocarbons from carbon monoxide and hydrogen by contacting said gases with a slurry of a catalyst composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants.

  14. Deep desulfurization of hydrocarbon fuels

    DOE Patents [OSTI]

    Song, Chunshan; Ma, Xiaoliang; Sprague, Michael J.; Subramani, Velu

    2012-04-17

    The invention relates to processes for reducing the sulfur content in hydrocarbon fuels such as gasoline, diesel fuel and jet fuel. The invention provides a method and materials for producing ultra low sulfur content transportation fuels for motor vehicles as well as for applications such as fuel cells. The materials and method of the invention may be used at ambient or elevated temperatures and at ambient or elevated pressures without the need for hydrogen.

  15. Kinetics and mechanisms of reactions involving small aromatic reactive intermediates

    SciTech Connect (OSTI)

    Lin, M.C.

    1993-12-01

    Small aromatic radicals such as C{sub 6}H{sub 5}, C{sub 6}H{sub 5}O and C{sub 6}H{sub 4} are key prototype species of their homologs. C{sub 6}H{sub 5} and its oxidation product, C{sub 6}H{sub 5}O are believed to be important intermediates which play a pivotal role in hydrocarbon combustion, particularly with regard to soot formation. Despite their fundamental importance, experimental data on the reaction mechanisms and reactivities of these species are very limited. For C{sub 6}H{sub 5}, most kinetic data except its reactions with NO and NO{sub 2}, were obtained by relative rate measurements. For C{sub 6}H{sub 5}O, the authors have earlier measured its fragmentation reaction producing C{sub 5}H{sub 5} + CO in shock waves. For C{sub 6}H{sub 4}, the only rate constant measured in the gas phase is its recombination rate at room temperature. The authors have proposed to investigate systematically the kinetics and mechanisms of this important class of molecules using two parallel laser diagnostic techniques--laser resonance absorption (LRA) and resonance enhanced multiphoton ionization mass spectrometry (REMPI/MS). In the past two years, study has been focused on the development of a new multipass adsorption technique--the {open_quotes}cavity-ring-down{close_quotes} technique for kinetic applications. The preliminary results of this study appear to be quite good and the sensitivity of the technique is at least comparable to that of the laser-induced fluorescence method.

  16. Analysis of low molecular weight hydrocarbons including 1,3-butadiene in engine exhaust gases using an aluminum oxide porous-layer open-tubular fused-silica column

    SciTech Connect (OSTI)

    Pelz, N.; Dempster, N.M.; Shore, P.R. )

    1990-05-01

    A method for the quantitative analysis of individual hydrocarbons in the C1-C8 range emitted in engine exhaust gases is described. The procedure provides base-line or near base-line resolution of C4 components including 1,3-butadiene. With a run time of less than 50 min, the light aromatics (benzene, toluene, ethyl benzene, p- and m-xylene, and o-xylene) are resolved during the same analysis as aliphatic hydrocarbons in the C1-C8 range. It is shown that typical 1,3-butadiene levels in engine exhaust are about 5 ppm at each of two engine conditions. Aromatic hydrocarbon levels show a dependence on engine operating conditions, benzene being about 20 ppm at high speed and about 40 ppm at idle.

  17. HYDROCARBON AND SULFUR SENSORS FOR SOFC SYSTEMS

    SciTech Connect (OSTI)

    A.M. Azad; Chris Holt; Todd Lesousky; Scott Swartz

    2003-11-01

    The following report summarizes work conducted during the Phase I program Hydrocarbon and Sulfur Sensors for SOFC Systems under contract No. DE-FC26-02NT41576. For the SOFC application, sensors are required to monitor hydrocarbons and sulfur in order to increase the operation life of SOFC components. This report discusses the development of two such sensors, one based on thick film approach for sulfur monitoring and the second galvanic based for hydrocarbon monitoring.

  18. Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Workshop: Agenda and Objectives | Department of Energy Workshop: Agenda and Objectives Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop: Agenda and Objectives Agenda and objectives for the Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop held March 18-19, 2015. Workshop Agenda and Objectives (146.49 KB) More Documents & Publications Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop Report Anaerobic MBR:

  19. Bioprocessing-Based Approach for Bitumen/Water/Fines Separation and Hydrocarbon Recovery from Oil Sands Tailings

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

    Brigmon, Robin L.; Berry, Christopher J.; Wade, Arielle; Simpson, Waltena

    2016-05-04

    Oil sands are a major source of oil, but their industrial processing generates tailings ponds that are an environmental hazard. The main concerns are mature fine tailings (MFT) composed of residual hydrocarbons, water, and fine clay. Tailings ponds include toxic contaminants such as heavy metals, and toxic organics including naphthenics. Naphthenic acids and polyaromatic hydrocarbons (PAHs) degrade very slowly and pose a long-term threat to surface and groundwater, as they can be transported in the MFT. Research into improved technologies that would enable densification and settling of the suspended particles is ongoing. In batch tests, BioTiger™, a microbial consortium thatmore » can metabolize PAHs, demonstrated improved oil sands tailings settling from a Canadian tailings pond. Results also showed, depending on the timing of the measurements, lower suspended solids and turbidity. Elevated total organic carbon was observed in the first 48 hours in the BioTiger™-treated columns and then decreased in overlying water. Oil sands tailings mixed with BioTiger™ showed a two-fold reduction in suspended solids within 24 hours as compared to abiotic controls. The tailings treated with BioTiger™ increased in microbial densities three orders of magnitude from 8.5 × 105 CFU/mL to 1.2 × 108 CFU/mL without any other carbon or energy source added, indicating metabolism of hydrocarbons and other available nutrients. Results demonstrated that bioaugmentation of BioTiger™ increased separation of organic carbon from particles in oil sands and enhanced settling with tailings with improved water quality.« less

  20. Vaporization and gasification of hydrocarbon feedstocks

    SciTech Connect (OSTI)

    Davies, H.S.; Garstang, J.H.; Timmins, C.

    1983-08-23

    Heavy hydrocarbon feedstocks, e.g. gas oils, are vaporized and subsequently gasified at high temperatures without pyrolytic degradation by first admixing the hydrocarbon with a hot gaseous reactant, e.g. product gas or steam, to bring the temperature of the mixture above that of the dew point of the hydrocarbon and thereafter raising the temperature of the mixture to above that at which pyrolysis of the hydrocarbon begins to be significant by admixture with further quantities of the reactant which are superheated thereby to bring the temperature of the resultant mixture to that required for effecting a catalytic gasification reaction.

  1. Membrane separation of hydrocarbons using cycloparaffinic solvents

    DOE Patents [OSTI]

    Kulkarni, Sudhir S.; Chang, Y. Alice; Gatsis, John G.; Funk, Edward W.

    1988-01-01

    Heavy crude oils which contain metal contaminants such as nickel, vanadium and iron may be separated from light hydrocarbon oils by passing a solution of the crude oil dissolved in a cycloparaffinic hydrocarbon solvent containing from about 5 to about 8 carbon atoms by passing through a polymeric membrane which is capable of maintaining its integrity in the presence of hydrocarbon compounds. The light hydrocarbon oils which possess relatively low molecular weights will be recovered as the permeate while the heavy oils which possess relatively high molecular weights as well as the metal contaminants will be recovered as the retentate.

  2. Nox reduction system utilizing pulsed hydrocarbon injection

    DOE Patents [OSTI]

    Brusasco, Raymond M.; Penetrante, Bernardino M.; Vogtlin, George E.; Merritt, Bernard T.

    2001-01-01

    Hydrocarbon co-reductants, such as diesel fuel, are added by pulsed injection to internal combustion engine exhaust to reduce exhaust NO.sub.x to N.sub.2 in the presence of a catalyst. Exhaust NO.sub.x reduction of at least 50% in the emissions is achieved with the addition of less than 5% fuel as a source of the hydrocarbon co-reductants. By means of pulsing the hydrocarbon flow, the amount of pulsed hydrocarbon vapor (itself a pollutant) can be minimized relative to the amount of NO.sub.x species removed.

  3. Membrane separation of hydrocarbons using cycloparaffinic solvents

    DOE Patents [OSTI]

    Kulkarni, S.S.; Chang, Y.A.; Gatsis, J.G.; Funk, E.W.

    1988-06-14

    Heavy crude oils which contain metal contaminants such as nickel, vanadium and iron may be separated from light hydrocarbon oils by passing a solution of the crude oil dissolved in a cycloparaffinic hydrocarbon solvent containing from about 5 to about 8 carbon atoms by passing through a polymeric membrane which is capable of maintaining its integrity in the presence of hydrocarbon compounds. The light hydrocarbon oils which possess relatively low molecular weights will be recovered as the permeate while the heavy oils which possess relatively high molecular weights as well as the metal contaminants will be recovered as the retentate.

  4. Enhanced Anaerobic Digestion and Hydrocarbon Precursor Production...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Enhanced Anaerobic Digestion and Hydrocarbon Precursor Production from Sewage Sludge Breakout Session 2-C: Biogas and Beyond: Challenges and Opportunities for Advanced Biofuels ...

  5. Enhanced Anaerobic Digestion and Hydrocarbon Precursor Production...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Presentation by Meltem Urgun-Demirtas, Argonne National Laboratory, during the "Targeting High-Value Challenges" panel at the Hydrogen, Hydrocarbons, and Bioproduct Precursors from ...

  6. George A. Olah, Carbocation and Hydrocarbon Chemistry

    Office of Scientific and Technical Information (OSTI)

    George A. Olah, Carbocation and Hydrocarbon Chemistry Resources with Additional Information * Patents George A. Olah Courtesy Rand Larson, Morningstar Productions George Olah ...

  7. Catalytic Upgrading Sugars To Hydrocarbons | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Sugars To Hydrocarbons Catalytic Upgrading Sugars To Hydrocarbons PDF on catalytic bioenergy process Catalytic Upgrading Sugars To Hydrocarbons (477.56 KB) More Documents & Publications Biological Conversion of Sugars To Hydrocarbons Technology Pathway Selection Effort Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway

  8. The use of fluorescence spectroscopy to monitor operation in petroleum hydrocracking units

    SciTech Connect (OSTI)

    Fetzer, J.C.

    1994-12-31

    The catalytic hydrocracking is used in refineries to convert petroleum-derived feedstocks into motor fuels and lubricating oils. Polycyclic aromatic hydrocarbons (PAHs) are produced as by-products in the process. The PAHs lead to a variety of process and product problems. The specific PAHs produced have been identified through the use of HPLC-DAD and fluorescence and mass spectroscopies. A set of production reactions have been determined that explain the observed PAHs. A synchronous-scanning fluorescence (SSF) method has been used to determine the levels of several kerge PAHs, including dicoronylene. This fifteen-ring PAH is the main cause of plugging in process piping, which necessitates expensive shutdown and cleaning of the process. This PAH is too large to be amenable to chromatographic methods. Its extremely low solubility, in a mixture of other PAHs show the advantages of SSF.

  9. Investigation of Nitro-Organic Compounds in Diesel Engine Exhaust: Final Report, February 2007 - April 2008

    SciTech Connect (OSTI)

    Dane, J.; Voorhees, K. J.

    2010-06-01

    The National Renewable Energy Laboratory upgraded its ReFUEL engine and vehicle testing facility to speciate unregulated gas-phase emissions. To complement this capability, the laboratory contracted with the Colorado School of Mines (CSM) to study the effects of soy biodiesel fuel and a diesel particle filter (DPF) on emissions of polycyclic aromatic hydrocarbons (PAH) and nitro-polycyclic aromatic hydrocarbons (NPAH). CSM developed procedures to sample diesel particulate matter (PM) emissions from raw and diluted exhaust, with and without a DPF. They also developed improved procedures for extracting PAH and NPAH from the PM and quantifying them with a gas chromatograph-electron monochromator mass spectrometer. The study found the DPF generally reduced PAH emissions by 1 to 3 orders of magnitude. PAH conversion was lowest for B100, suggesting that PAHs were forming in the DPF. Orders of magnitude reductions were also found for NPAH emissions exiting the DPF.

  10. Conversion of organic solids to hydrocarbons

    DOE Patents [OSTI]

    Greenbaum, Elias

    1995-01-01

    A method of converting organic solids to liquid and gaseous hydrocarbons includes impregnating an organic solid with photosensitizing ions and exposing the impregnated solid to light in a non-oxidizing atmosphere for a time sufficient to photocatalytically reduce the solid to at least one of a liquid and a gaseous hydrocarbon.

  11. Conversion of organic solids to hydrocarbons

    DOE Patents [OSTI]

    Greenbaum, E.

    1995-05-23

    A method of converting organic solids to liquid and gaseous hydrocarbons includes impregnating an organic solid with photosensitizing ions and exposing the impregnated solid to light in a non-oxidizing atmosphere for a time sufficient to photocatalytically reduce the solid to at least one of a liquid and a gaseous hydrocarbon. 5 Figs.

  12. Device for aqueous detection of nitro-aromatic compounds

    DOE Patents [OSTI]

    Reagen, W.K.; Schulz, A.L.; Ingram, J.C.; Lancaster, G.D.; Grey, A.E.

    1994-04-26

    This invention relates to a compact and portable detection apparatus for nitro-aromatic based chemical compounds, such as nitrotoluenes, dinitrotoluenes, and trinitrotoluene (TNT). The apparatus is based upon the use of fiber optics using filtered light. The preferred process of the invention relies upon a reflective chemical sensor and optical and electronic components to monitor a decrease in fluorescence when the nitro-aromatic molecules in aqueous solution combine and react with a fluorescent polycyclic aromatic compound. 4 figures.

  13. Device for aqueous detection of nitro-aromatic compounds

    DOE Patents [OSTI]

    Reagen, William K.; Schulz, Amber L.; Ingram, Jani C.; Lancaster, Gregory D.; Grey, Alan E.

    1994-01-01

    This invention relates to a compact and portable detection apparatus for ro-aromatic based chemical compounds, such as nitrotoluenes, dinitrotoluenes, and trinitrotoluene (TNT). The apparatus is based upon the use of fiber optics using filtered light. The preferred process of the invention relies upon a reflective chemical sensor and optical and electronic components to monitor a decrease in fluorescence when the nitro-aromatic molecules in aqueous solution combine and react with a fluorescent polycyclic aromatic compound.

  14. 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.

  15. Low-Temperature Hydrocarbon/CO Oxidation Catalysis in Support...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications Low-Temperature HydrocarbonCO Oxidation Catalysis in Support of HCCI Emission Control Low-Temperature HydrocarbonCO Oxidation Catalysis in Support ...

  16. Conversion of Ethanol to Hydrocarbons on Hierarchical HZSM-5...

    Office of Scientific and Technical Information (OSTI)

    Conversion of Ethanol to Hydrocarbons on Hierarchical HZSM-5 Zeolites Citation Details In-Document Search Title: Conversion of Ethanol to Hydrocarbons on Hierarchical HZSM-5 ...

  17. Ethanol-to-Hydrocarbon Technology Moves Closer to Commercialization...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ethanol-to-Hydrocarbon Technology Moves Closer to Commercialization Ethanol-to-Hydrocarbon Technology Moves Closer to Commercialization December 16, 2015 - 2:23pm Addthis Dr. ...

  18. EERE Success Story-Ethanol-to-Hydrocarbon Technology Moves Closer...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ethanol-to-Hydrocarbon Technology Moves Closer to Commercialization EERE Success Story-Ethanol-to-Hydrocarbon Technology Moves Closer to Commercialization January 27, 2016 - 1:40pm ...

  19. BIOTIGER, A NATURAL MICROBIAL PRODUCT FOR ENHANCED HYDROCARBON RECOVERY FROM OIL SANDS.

    SciTech Connect (OSTI)

    Brigmon, R; Topher Berry, T; Whitney Jones, W; Charles Milliken, C

    2008-05-27

    BioTiger{trademark} is a unique microbial consortia that resulted from over 8 years of extensive microbiology screening and characterization of samples collected from a century-old Polish waste lagoon. BioTiger{trademark} shows rapid and complete degradation of aliphatic and aromatic hydrocarbons, produces novel surfactants, is tolerant of both chemical and metal toxicity and shows good activity at temperature and pH extremes. Although originally developed and used by the U.S. Department of Energy for bioremediation of oil-contaminated soils, recent efforts have proven that BioTiger{trademark} can also be used to increase hydrocarbon recovery from oil sands. This enhanced ex situ oil recovery process utilizes BioTiger{trademark} to optimize bitumen separation. A floatation test protocol with oil sands from Ft. McMurray, Canada was used for the BioTiger{trademark} evaluation. A comparison of hot water extraction/floatation test of the oil sands performed with BioTiger{trademark} demonstrated a 50% improvement in separation as measured by gravimetric analysis in 4 h and a five-fold increase at 25 hr. Since BioTiger{trademark} performs well at high temperatures and process engineering can enhance and sustain metabolic activity, it can be applied to enhance recovery of hydrocarbons from oil sands or other complex recalcitrant matrices.

  20. Biodegradation of petroleum hydrocarbons in fractured, unsaturated dolomite at a field site

    SciTech Connect (OSTI)

    McLinn, E.L.; Rehm, B.W.

    1997-12-31

    Gasoline constituents were detected in unsaturated soil and rock during abandonment of a leaky underground storage tank (UST). The unsaturated sequence beneath the former UST consists of 90 feet of silty till, fractured dolomite, and friable sandstone. Pore gas probes were installed in each of the unsaturated units, both in the source area and in a background on-site location. Pore gas samples were collected to evaluate the nature, extent, and fate of residual hydrocarbons in the vadose zone. Pore gas from the till and dolomite in the source area was enriched in petroleum hydrocarbons and carbon dioxide, and was depleted in oxygen, relative to pore gas from the background area. During two years of ground water monitoring at the site, methyl tertiary butyl ether was periodically detected in the ground water beneath the source area as pulses of recharge passed through the unsaturated zone, but not other gasoline constituents were detected. Apparently, the most degradable fraction of the gasoline (aromatic hydrocarbons) is being attenuated in the vadose zone before the water table is reached.

  1. Using supercritical fluids to refine hydrocarbons

    DOE Patents [OSTI]

    Yarbro, Stephen Lee

    2015-06-09

    A system and method for reactively refining hydrocarbons, such as heavy oils with API gravities of less than 20 degrees and bitumen-like hydrocarbons with viscosities greater than 1000 cp at standard temperature and pressure, using a selected fluid at supercritical conditions. A reaction portion of the system and method delivers lightweight, volatile hydrocarbons to an associated contacting unit which operates in mixed subcritical/supercritical or supercritical modes. Using thermal diffusion, multiphase contact, or a momentum generating pressure gradient, the contacting unit separates the reaction products into portions that are viable for use or sale without further conventional refining and hydro-processing techniques.

  2. Selective photooxidation of hydrocarbons in zeolites by oxygen

    DOE Patents [OSTI]

    Frei, Heinz; Blatter, Fritz; Sun, Hai

    1998-01-01

    A selective photooxidation process for the conversion of hydrocarbon molecules to partially oxygenated derivatives, which comprises the steps of adsorbing a hydrocarbon and oxygen onto a dehydrated zeolite support matrix to form a hydrocarbon-oxygen contact pair, and subsequently exposing the hydrocarbon-oxygen contact pair to visible light, thereby forming a partially oxygenated derivative.

  3. Enhanced Anaerobic Digestion and Hydrocarbon Precursor Production

    Office of Energy Efficiency and Renewable Energy (EERE)

    Presentation by Meltem Urgun-Demirtas, Argonne National Laboratory, during the "Targeting High-Value Challenges" panel at the Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop held March 18–19, 2015.

  4. George A. Olah, Carbocation and Hydrocarbon Chemistry

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

    George A. Olah, Carbocation and Hydrocarbon Chemistry Resources with Additional Information * Patents George A. Olah Courtesy Rand Larson, Morningstar Productions George Olah received the 1994 Nobel Prize in Chemistry "for his contribution to carbocation chemistry" and his 'role in the chemistry of hydrocarbons. In particular, he developed superacids ... that are much stronger than ordinary acids, are non-nucleophilic, and are fluid at low temperatures. In such media ... carbocations

  5. Department of Chemistry | Center for Catalytic Hydrocarbon

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

    Functionalization Department of Chemistry Faculty & Research Outreach Programs Graduate Studies Events & Seminars Undergraduate Studies Contact Us Faculty & Research > Research Centers & Programs > Center for Catalytic Hydrocarbon Functionalization CCHF Center for Catalytic Hydrocarbon Functionalization Catalysts are central to the efficient and clean utilization of energy resources, and they impact all aspects of the energy sector. With the University of Virginia as

  6. Upgrading heavy hydrocarbon oils using sodium hypochlorite

    SciTech Connect (OSTI)

    Rankel, L.A.

    1986-07-22

    A process is described for demetallizing a residual hydrocarbon fraction comprising: (a) contacting the hydrocarbon fraction with an aqueous solution of a hypochlorite salt; (b) separating the mixture into an aqueous phase and an oil phase; (c) contacting the oil phase with a deasphalting solvent and (d) obtaining by separation a product comprising a demetallized oil fraction suitable for use as a feedstock for catalytic processing.

  7. Syngas Upgrading to Hydrocarbon Fuels Technology Pathway | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Syngas Upgrading to Hydrocarbon Fuels Technology Pathway Syngas Upgrading to Hydrocarbon Fuels Technology Pathway This technology pathway case investigates the upgrading of woody biomass derived synthesis gas (syngas) to hydrocarbon biofuels. While this specific discussion focuses on the conversion of syngas via a methanol intermediate to hydrocarbon blendstocks, there are a number of alternative conversion routes for production of hydrocarbons through a wide array of intermediates

  8. Coupling of oxidative dehydrogenation and aromatization reactions of butane

    SciTech Connect (OSTI)

    Xu, Wen-Qing; Suib, S.L. )

    1994-01-01

    Coupling of oxidative dehydrogenation and aromatization of butane by using a dual function catalyst has led to a significant enhancement of the yields (from 25 to 40%) and selectivities to aromatics (from 39 to 64%). Butane is converted to aromatics by using either zinc-promoted [Ga]-ZSM-5 or zinc and gallium copromoted [Fe]-ZSM-5 zeolite as a catalyst. However, the formation of aromatics is severely limited by hydrocracking of butane to methane, ethane, and propane due to the hydrogen formed during aromatization reactions. On the other hand, the oxidative dehydrogenation of butane to butene over molybdate catalysts is found to be accompanied by a concurrent undesirable reaction, i.e., total oxidation. When two of these reactions (oxidative dehydrogenation and aromatization of butane) are coupled by using a dual function catalyst they have shown to complement each other. It is believed that the rate-limiting step for aromatization (butane to butene) is increased by adding an oxidative dehydrogenation catalyst (Ga-Zn-Mg-Mo-O). The formation of methane, ethane, and propane was suppressed due to the removal of hydrogen initially formed as water. Studies of ammonia TPD show that the acidities of [Fe]-ZSM-5 are greatly affected by the existence of metal oxides such as Ga[sub 2]O[sub 3], MgO, ZnO, and MoO[sub 3]. 40 refs., 9 figs., 1 tab.

  9. Selective Sorbents For Purification Of Hydrocarbons

    DOE Patents [OSTI]

    Yang, Ralph T.; Yang, Frances H.; Takahashi, Akira; Hernandez-Maldonado, Arturo J.

    2006-04-18

    A method for removing thiophene and thiophene compounds from liquid fuel includes contacting the liquid fuel with an adsorbent which preferentially adsorbs the thiophene and thiophene compounds. The adsorption takes place at a selected temperature and pressure, thereby producing a non-adsorbed component and a thiophene/thiophene compound-rich adsorbed component. The adsorbent includes either a metal or a metal ion that is adapted to form p-complexation bonds with the thiophene and/or thiophene compounds, and the preferential adsorption occurs by p-complexation. A further method includes selective removal of aromatic compounds from a mixture of aromatic and aliphatic compounds.

  10. Selective sorbents for purification of hydrocarbons

    DOE Patents [OSTI]

    Yang, Ralph T.; Yang, Frances H.; Takahashi, Akira; Hernandez-Maldonado, Arturo J.

    2006-05-30

    A method for removing thiophene and thiophene compounds from liquid fuel includes contacting the liquid fuel with an adsorbent which preferentially adsorbs the thiophene and thiophene compounds. The adsorption takes place at a selected temperature and pressure, thereby producing a non-adsorbed component and a thiophene/thiophene compound-rich adsorbed component. The adsorbent includes either a metal or a metal cation that is adapted to form .pi.-complexation bonds with the thiophene and/or thiophene compounds, and the preferential adsorption occurs by .pi.-complexation. A further method includes selective removal of aromatic compounds from a mixture of aromatic and aliphatic compounds.

  11. Selective sorbents for purification of hydrocarbons

    DOE Patents [OSTI]

    Yang, Ralph T.; Hernandez-Maldonado, Arturo J.; Yang, Frances H.; Takahashi, Akira

    2006-08-22

    A method for removing thiophene and thiophene compounds from liquid fuel includes contacting the liquid fuel with an adsorbent which preferentially adsorbs the thiophene and thiophene compounds. The adsorption takes place at a selected temperature and pressure, thereby producing a non-adsorbed component and a thiophene/thiophene compound-rich adsorbed component. The adsorbent includes either a metal or a metal cation that is adapted to form .pi.-complexation bonds with the thiophene and/or thiophene compounds, and the preferential adsorption occurs by .pi.-complexation. A further method includes selective removal of aromatic compounds from a mixture of aromatic and aliphatic compounds.

  12. Nano-structured noble metal catalysts based on hexametallate architecture for the reforming of hydrocarbon fuels

    DOE Patents [OSTI]

    Gardner, Todd H.

    2015-09-15

    Nano-structured noble metal catalysts based on hexametallate lattices, of a spinel block type, and which are resistant to carbon deposition and metal sulfide formation are provided. The catalysts are designed for the reforming of hydrocarbon fuels to synthesis gas. The hexametallate lattices are doped with noble metals (Au, Pt, Rh, Ru) which are atomically dispersed as isolated sites throughout the lattice and take the place of hexametallate metal ions such as Cr, Ga, In, and/or Nb. Mirror cations in the crystal lattice are selected from alkali metals, alkaline earth metals, and the lanthanide metals, so as to reduce the acidity of the catalyst crystal lattice and enhance the desorption of carbon deposit forming moieties such as aromatics. The catalysts can be used at temperatures as high as 1000.degree. C. and pressures up to 30 atmospheres. A method for producing these catalysts and applications of their use also is provided.

  13. Process for catalytic cracking of heavy hydrocarbon feed to lighter products

    SciTech Connect (OSTI)

    Herbst, J.A.; Owen, H.; Schipper, P.H.

    1990-05-29

    This patent describes a process for catalytic cracking of a feed of hydrocarbons boiling in the gas oil and heavier boiling range to lighter products by contacting the feed at catalytic cracking conditions and catalytically cracking the feed to lighter products with a cracking catalyst. It comprises: a mixture of separate particles of: a bulk conversion cracking catalyst containing at least one component with an equivalent pore size of at least about 7 angstroms in a matrix, the bulk conversion cracking catalyst having fluidization properties which permit use in a fluidized or moving bed catalytic cracking reactor; a light paraffin upgrading catalyst comprising at least one zeolite having a constraint index of 1--12 and paraffin cracking/isomerization activity; and, a light paraffin upgrading catalyst comprising at least one zeolite having a constraint index of 1--12 and paraffin aromatization activity; and wherein the upgrading catalysts have substantially the same fluidization properties as the bulk conversion cracking catalyst.

  14. Development of Advanced Membranes Technology Platform for Hydrocarbon Separations

    SciTech Connect (OSTI)

    Kalthod, Dr Dilip

    2010-03-01

    selected for membrane development. A novel dope composition and spinning process were developed, which provide a new approach to controlling membrane porosity and wall and skin morphology. A hollow-fiber membrane with an external dense “skin” was produced that has a high water vapor permeation coefficient and selectivity, durability when in operation at 1000 psig and 70°C, and the ability to withstand aromatic and aliphatic hydrocarbon vapors for an extended period. The fiber meets the technical requirements for a commercial product offering in gas dehydration. It can be readily manufactured with some changes in process equipment and process conditions, and is an excellent candidate for scale-up to full-size membrane modules.

  15. Syngas Upgrading to Hydrocarbon Fuels Technology Pathway

    SciTech Connect (OSTI)

    Talmadge, M.; Biddy, Mary J.; Dutta, Abhijit; Jones, Susanne B.; Meyer, Pimphan A.

    2013-03-31

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This pathway case investigates the upgrading of biomass derived synthesis gas (‘syngas’) to hydrocarbon biofuels. While this specific discussion focuses on the conversion of syngas via a methanol intermediate to hydrocarbon blendstocks, there are a number of alternative conversion routes for production of hydrocarbons through a wide array of intermediates from syngas. Future work will also consider the variations to this pathway to determine the most economically viable and risk adverse conversion route. Technical barriers and key research needs have been identified that should be pursued for the syngas to hydrocarbon pathway to be competitive with petroleum-derived gasoline, diesel and jet range blendstocks.

  16. A role of hydrocarbon reaction for NO{sub x} formation and reduction in fuel-rich pulverized coal combustion

    SciTech Connect (OSTI)

    Taniguchi, Masayuki; Kamikawa, Yuki; Okazaki, Teruyuki; Yamamoto, Kenji; Orita, Hisayuki

    2010-08-15

    We have investigated an index for modeling a NO{sub x} reaction mechanism of pulverized coal combustion. The reaction mechanism of coal nitrogen was examined by drop-tube furnace experiments under various burning conditions. We proposed the gas phase stoichiometric ratio (SRgas) as a key index to evaluate NO{sub x} concentration in fuel-rich flames. The SRgas was defined as: SRgas {identical_to} amount of fuel required for stoichiometry combustion/amount of gasified fuel where, the amount of gasified fuel was defined as the amount of fuel which had been released to the gas phase by pyrolysis, oxidation and gasification reactions. When SRgas < 1.0, NO{sub x} concentration was strongly influenced by the value of SRgas. In this condition, the NO{sub x} concentration was hardly influenced by coal type, particle diameter, or reaction time. We developed a model to analyze NO{sub x} and XN(HCN, NH{sub 3}) concentrations for pulverized coal/air combustion and coal/CO{sub 2}/O{sub 2} combustion, based on the index. NO{sub x} and XN concentrations did not reproduce the experimental results without considering reactions between hydrocarbons and NO{sub x}. The hydrocarbon reaction was important for both NO{sub x} and XN, especially for air combustion. In the present model, an empirical formula was used to estimate the total concentration of hydrocarbons in coal flame. The reaction of heavy hydrocarbons which had plural aromatic rings was very important to analyze the reaction mechanism of hydrocarbons for coal combustion in detail. When burning temperature and SRgas were the same, total hydrocarbon concentration in a coal flame was larger than that of a light gaseous hydrocarbon flame. Total hydrocarbon concentration in oxy-fuel combustion was lower than that in air combustion. We verified the proposed model by experimental results obtained for a drop-tube furnace and a laboratory-scale furnace that had an installed low-NO{sub x} burner. (author)

  17. Selective Conversion of Lignin into Simple Aromatic Compounds - Energy

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

    Innovation Portal Selective Conversion of Lignin into Simple Aromatic Compounds Great Lakes Bioenergy Research Center Contact GLBRC About This Technology Technology Marketing Summary Lignin is a major component of non-edible biomass (15-30 percent by weight; 40 percent by energy). It is a cheap byproduct of pulp and biofuel production and is one of the few naturally occurring sources of high-volume aromatic compounds. Converting lignin's complex biopolymer structure into simple organic

  18. Methods for dispersing hydrocarbons using autoclaved bacteria

    DOE Patents [OSTI]

    Tyndall, Richard L.

    1996-01-01

    A method of dispersing a hydrocarbon includes the steps: providing a bacterium selected from the following group: ATCC 85527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures thereof; autoclaving the bacterium to derive a dispersant solution therefrom; and contacting the dispersant solution with a hydrocarbon to disperse the hydrocarbon. Moreover, a method for preparing a dispersant solution includes the following steps: providing a bacterium selected from the following group: ATCC 75527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures thereof; and autoclaving the bacterium to derive a dispersant solution therefrom.

  19. Methods for dispersing hydrocarbons using autoclaved bacteria

    DOE Patents [OSTI]

    Tyndall, R.L.

    1996-11-26

    A method of dispersing a hydrocarbon includes the following steps: providing a bacterium selected from the following group: ATCC 85527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures; autoclaving the bacterium to derive a dispersant solution; and contacting the dispersant solution with a hydrocarbon to disperse the hydrocarbon. Moreover, a method for preparing a dispersant solution includes the following steps: providing a bacterium selected from the following group: ATCC 75527, ATCC 75529, and ATCC 55638, a mutant of any one of these bacteria possessing all the identifying characteristics of any one of these bacteria, and mixtures; and autoclaving the bacterium to derive a dispersant solution.

  20. Using supercritical fluids to refine hydrocarbons

    DOE Patents [OSTI]

    Yarbro, Stephen Lee

    2014-11-25

    This is a method to reactively refine hydrocarbons, such as heavy oils with API gravities of less than 20.degree. and bitumen-like hydrocarbons with viscosities greater than 1000 cp at standard temperature and pressure using a selected fluid at supercritical conditions. The reaction portion of the method delivers lighter weight, more volatile hydrocarbons to an attached contacting device that operates in mixed subcritical or supercritical modes. This separates the reaction products into portions that are viable for use or sale without further conventional refining and hydro-processing techniques. This method produces valuable products with fewer processing steps, lower costs, increased worker safety due to less processing and handling, allow greater opportunity for new oil field development and subsequent positive economic impact, reduce related carbon dioxide, and wastes typical with conventional refineries.

  1. Bioremediation of Petroleum Hydrocarbon Contaminated Sites

    SciTech Connect (OSTI)

    Fallgren, Paul

    2009-03-30

    Bioremediation has been widely applied in the restoration of petroleum hydrocarbon-contaminated. Parameters that may affect the rate and efficiency of biodegradation include temperature, moisture, salinity, nutrient availability, microbial species, and type and concentration of contaminants. Other factors can also affect the success of the bioremediation treatment of contaminants, such as climatic conditions, soil type, soil permeability, contaminant distribution and concentration, and drainage. Western Research Institute in conjunction with TechLink Environmental, Inc. and the U.S. Department of Energy conducted laboratory studies to evaluate major parameters that contribute to the bioremediation of petroleum-contaminated drill cuttings using land farming and to develop a biotreatment cell to expedite biodegradation of hydrocarbons. Physical characteristics such as soil texture, hydraulic conductivity, and water retention were determined for the petroleum hydrocarbon contaminated soil. Soil texture was determined to be loamy sand to sand, and high hydraulic conductivity and low water retention was observed. Temperature appeared to have the greatest influence on biodegradation rates where high temperatures (>50 C) favored biodegradation. High nitrogen content in the form of ammonium enhanced biodegradation as well did the presence of water near field water holding capacity. Urea was not a good source of nitrogen and has detrimental effects for bioremediation for this site soil. Artificial sea water had little effect on biodegradation rates, but biodegradation rates decreased after increasing the concentrations of salts. Biotreatment cell (biocell) tests demonstrated hydrocarbon biodegradation can be enhanced substantially when utilizing a leachate recirculation design where a 72% reduction of hydrocarbon concentration was observed with a 72-h period at a treatment temperature of 50 C. Overall, this study demonstrates the investigation of the effects of

  2. Multiple-stage hydroprocessing of hydrocarbon oil

    SciTech Connect (OSTI)

    Simpson, H.D.; McArthur, D.P.

    1984-02-14

    In the catalytic hydroprocessing of hydrocarbons, a hydrocarbon oil is successively contacted with a first hydroprocessing catalyst in a first reaction zone and a second hydroprocessing catalyst in a second reaction zone. The first catalyst has an average pore diameter at least about 30 angstroms larger than the second catalyst, although both have narrow pore size distributions wherein at least about 90 percent of the total pore volume is in pores of diameter from about 100 angstroms to about 300 angstroms, and with essentially all the pores having diameters greater than 100 angstroms.

  3. Catalysts for synthesizing various short chain hydrocarbons

    DOE Patents [OSTI]

    Colmenares, Carlos (Alamo, CA)

    1991-01-01

    Method and apparatus (10), including novel photocatalysts, are disclosed for the synthesis of various short chain hydrocarbons. Light-transparent SiO.sub.2 aerogels doped with photochemically active uranyl ions (18) are fluidized in a fluidized-bed reactor (12) having a transparent window (16), by hydrogen and CO, C.sub.2 H.sub.4 or C.sub.2 H.sub.6 gas mixtures (20), and exposed to radiation (34) from a light source (32) external to the reactor (12), to produce the short chain hydrocarbons (36).

  4. Process for hydrogenation of hydrocarbon tars

    DOE Patents [OSTI]

    Dolbear, Geoffrey E.

    1978-07-18

    Hydrocarbon tars of high asphaltene content such as tars obtained from pyrolysis of coal are dissolved in a solvent formed from the hydrogenation of the coal tars, and the resultant mixture hydrogenated in the presence of a catalyst at a pressure from about 1500 to 5000 psig at a temperature from about 500.degree. F to about the critical temperature of the solvent to form a light hydrocarbon as a solvent for the tars. Hydrogen content is at least three times the amount of hydrogen consumed.

  5. Enhanced Anaerobic Digestion and Hydrocarbon Precursor Production

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrogen, Hydrocarbons, and Bioproduct Precursors from Wastewaters Workshop Enhanced Anaerobic Digestion and Hydrocarbon Precursor Production March 18-19, 2015 Meltem Urgun-Demirtas, Ph. D. Argonne National Laboratory Total Potential Energy at Municipal WWTPs Basis Thermal energy (MMBtu/ year) Electric power (kWh/year) Total energy potential (MMBtu /year) Reference 1 MGD wastewater equates 26 kW of electric capacity and 2.4 MMBtu/day of thermal energy 3.52 × 10 7 9.11 × 10 9 6.65 × 10 7 EPA,

  6. Catalytic hydroprocessing of simulated heavy coal liquids; 2: Reaction networks of aromatic hydrocarbons and sulfur and oxygen heterocyclic compounds

    SciTech Connect (OSTI)

    Girgis, M.J. . Dept. of Chemical Engineering Mobil Research and Development Corp., Princeton, NJ . Central Research Lab.); Gates, B.C. . Dept. of Chemical Engineering)

    1994-10-01

    The reactivity of a mixture simulating a coal liquid from the SRC-II process, with the organonitrogen compounds excluded, was characterized at 350 C and 171 atm; the catalyst was presulfided Ni-Mo/[gamma]-Al[sub 2]O[sub 3]. The reaction products were identified and analyzed quantitatively. Approximate reaction networks were determined for the simultaneously reacting phenanthrene, pyrene, fluoranthene, dibenzothiophene, and dibenzofuran. The reactions in each network are approximated as first order in the organic reactant. The proposed networks allow clarification of pathways that had been proposed earlier with less complete evidence; some previously unidentified pathways have also been identified. The results represent the first determination of quantitative networks of simultaneously reacting compounds in hydroprocessing and help to lay the foundation for modeling of hydroprocessing.

  7. Laser photoionization time-of-flight mass spectrometry of nitrated polycyclic aromatic hydrocarbons and nitrated heterocyclic compounds. Master's thesis

    SciTech Connect (OSTI)

    Noyes, R.A.

    1993-01-01

    Partial Contents: Laser Desorption-Laser Photoionization Time-of-Flight Mass Spectrometry; Basic Principles of TOFMS; Factors Affecting Flight Time; Source of Broadening; Laser Desorption; Theory of Multiphoton Ionization: Application to Mass Spectrometry; Quantum Theory of MPI; Time-Dependent Perturbation Theory; Time-Dependent Coefficients; Probability of a Two-Photon Process; and Attributes of R2PI.

  8. Solubilities and other physical parameters of aromatic hydrocarbons in water and aqueous sodium chloride solutions as determined by headspace analysis

    SciTech Connect (OSTI)

    Lowry, M.A.H.

    1991-12-31

    The solubility, Henry`s law constant, aqueous-vapor partition coefficients, and oil-aqueous distribution coefficients of benzene, toluene, ethylbenzene, o-xylene,m-xylene and p-xylene were determined in water and aqueous sodium chloride solutions at 25C. Values are in agreement with using gas chromatography of headspace literature. The salting-out effect of sodium chloride on the solute properties measured was illustrated using the empirical relationship deduced by Setschenow (1889). The empirical relationship predicts that the logarithm of solubility will be a function of ionic strength. The solubility data obtained in this work obeys this relationship. It was also found that the logarithm of the Henry`s law constant, partition coefficient, and distribution coefficient are linear functions of ionic strength. 10 tabs, 6 figs.

  9. PHOTODISSOCIATION OF THE DIACETYLENE DIMER AND IMPLICATIONS FOR HYDROCARBON GROWTH IN TITAN'S ATMOSPHERE

    SciTech Connect (OSTI)

    Huang Cunshun; Silva, Ruchira; Gichuhi, Wilson K.; Suits, Arthur G.; Zhang Fangtong; Kaiser, Ralf I.; Kislov, Vadim V.; Mebel, Alexander M.

    2010-05-10

    The surface of Titan is obscured by multiple aerosol layers whose composition and formation mechanism have remained poorly understood. These organic haze layers are believed to arise from photolysis and electron impact triggered chemistry in the dense nitrogen (N{sub 2}) and methane (CH{sub 4}) atmosphere involving highly unsaturated hydrocarbon molecules such as acetylene (HCCH), diacetylene (HCCCCH), and triacetylene (HCCCCCCH). Here we show via laboratory studies combined with electronic structure calculations that the photodissociation of the diacetylene dimer ((HCCCCH){sub 2}) readily initiates atomic hydrogen loss and atomic hydrogen transfer reactions forming two prototypes of resonantly stabilized free radicals, C{sub 4}H{sub 3} and C{sub 8}H{sub 3}, respectively. These structures represent hydrogenated polyynes which can neither be synthesized via traditional photodissociation pathways of the monomer nor via hydrogen addition to the polyynes. The photodissociation dynamics of mixed dimers involving acetylene, diacetylene, and even triacetylene present a novel, hitherto overlooked reaction class and show the potential to synthesize more complex, resonantly stabilized free radicals considered to be major building blocks to polycyclic aromatic hydrocarbons in Titan's low-temperature atmosphere.

  10. Low-Temperature Hydrocarbon/CO Oxidation Catalysis in Support...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low-Temperature HydrocarbonCO Oxidation Catalysis in Support of HCCI Emission Control Low-Temperature HydrocarbonCO Oxidation Catalysis in Support of HCCI Emission Control Lean ...