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1

LINEAR TO NON-LINEAR RHEOLOGY OF WHEAT FLOUR DOUGH TREVOR S.K. NG1  

E-Print Network (OSTI)

LINEAR TO NON-LINEAR RHEOLOGY OF WHEAT FLOUR DOUGH TREVOR S.K. NG1 , GARETH H. MCKINLEY1 *, MADESH.9.2006 Abstract: We provide an overview of transient extensional rheometry techniques for wheat flour doughs wheat flour; mixed to a constant time (360 s/peak-mixed) and a fixed water ratio by weight (66

2

Trevor Sears  

NLE Websites -- All DOE Office Websites (Extended Search)

(631) 344-5815 (BNL) (631) 632-7960 (SUNY-SB) e-mail Gas-Phase Molecular Dynamics Curriculum Vitae Education B.Sc. Chemistry, University of Southampton, UK 1975 Ph.D. Chemical...

3

Dissolution Behavior of Rhodium into Molten Slag  

Science Conference Proceedings (OSTI)

Determination of FeO Containing Liquid Slag Surface Tensions Using the Sessile Drop Method · Dissolution Behavior of Rhodium into Molten Slag.

4

Slide 1  

U.S. Energy Information Administration (EIA) Indexed Site

| Making Sense of Chinese Energy Statistics | Making Sense of Chinese Energy Statistics 1 10 East 40 th Street, Suite 3601, New York, NY 10016 Tel: +1.212.532.1158 | Fax: +1.212.532.1162 | Web: www.rhgroup.net Address: 5 Columbus Circle, New York, NY 10019 | Tel: +1.212.532.1158 | Fax: +1.212.532.1162 | Web: www.rhg.com Making Sense of Chinese Energy Statistics Trevor Houser Partner, Rhodium Group tghouser@rhg,com EIA | June 18, 2013 EIA | Making Sense of Chinese Energy Statistics 2 Why Good Chinese Energy Statistics Matter for Energy Markets Share of Global Demand Growth Source: Historical data is 2002-2012 from BP Statistical Review. Projections are from the IEA's 2012 World Energy Outlook "New Policies Scenario" 87% 44% 14% 8% 30% 66% 20% 56% 31% 68% 21% 37% 53%

5

Slide 1  

U.S. Energy Information Administration (EIA) Indexed Site

Conference | Powering China's Growth Conference | Powering China's Growth 1 10 East 40 th Street, Suite 3601, New York, NY 10016 Tel: +1.212.532.1158 | Fax: +1.212.532.1162 | Web: www.rhgroup.net 10 East 40 th Street, Suite 3601, New York, NY 10016 Tel: +1.212.532.1158 | Fax: +1.212.532.1162 | Web: www.rhgroup.net Powering China's Growth Electricity Market Projections and Global Implications Trevor Houser Partner, Rhodium Group (RHG) EIA Conference Washington, DC tghouser@rhgroup.net April 27, 2011 EIA Conference | Powering China's Growth 2 China Has Commendable Clean Energy Ambitions Projected Capacity Additions 2010-2020 Source: US-BAU is AEO 2011. US-C&T is a generic economy-wide cap-and-trade program with banking and borrowing , international offsets and emissions reduction targets of 17% below

6

Agnes Houser | Y-12 National Security Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

Y-12? (4:37) Did you live in the Y-12 dormitories? (2:06) Did you remember a red safety line in your work area? (1:03) Did you know you were working on a secret weapon? (3:58) When...

7

Mesoporous Silica-Supported Rhodium Nanocatalysts for Selective...  

NLE Websites -- All DOE Office Websites (Extended Search)

Mesoporous Silica-Supported Rhodium Nanocatalysts for Selective Production of Ethanol From Syngas and Conversion of Ethanol to Hydrogen Description Coal will likely play a major...

8

Platinum-Rhodium Alloys(3.5 to 40% Rh)  

Science Conference Proceedings (OSTI)

Table 8   Typical properties of platinum-rhodium alloys...strength Elongation (a) , % Hardness, HB Density Electrical resistivity (b) , nΩ · m Temperature coefficient (c) , per °C MPa ksi g/cm 3 lb/in. 3 3.5% annealed 170 25 35 60 20.90 0.755 166 0.0022 3.5% hard (d) 415 60 � 120 5.0% annealed 205 30 35 70 20.65 0.746 175 0.0020 5.0% hard (d) 485 70 � 130 10%...

9

CO HYDROGENATION OVER CLEAN AND OXIDIZED RHODIUM FOIL AND SINGLE CRYSTAL CATALYSTS. CORRELATIONS OF CATALYST ACTIVITY, SELECTIVITY AND SURFACE COMPOSITION  

E-Print Network (OSTI)

AND OXIDIZED RHODIUM FOIL AND SINGLE CRYSTAL CATALYSTS.CORRELATIONS OF CATALYST ACTIVITY, SELECTIVITY AND SURFACEobserved over the clean Rh catalysts during the catalyzed

Castner, D.G.

2012-01-01T23:59:59.000Z

10

Rhodium mediated bond activation: from synthesis to catalysis  

SciTech Connect

Recently, our lab has developed monoanionic tridentate ligand, To{sup R}, showing the corresponding coordination chemistry and catalyst reactivity of magnesium, zirconium, zinc and iridium complexes. This thesis details synthetic chemistry, structural study and catalytic reactivity of the To{sup R}-supported rhodium compounds. Tl[To{sup R}] has been proved to be a superior ligand transfer agent for synthesizing rhodium complexes. The salt metathesis route of Tl[To{sup M}] with [Rh({mu}-Cl)(CO)]{sub 2} and [Rh({mu}- Cl)(COE)]{sub 2} gives To{sup M}Rh(CO){sub 2} (2.2) and To{sup M}RhH({eta}{sup 3}-C{sub 8}H{sub 13}) (3.1) respectively while Tl[To{sup P}] with [Rh({mu}-Cl)(CO)]{sub 2} affords To{sup P}Rh(CO){sub 2} (2.3). 2.2 reacts with both strong and weak electrophiles, resulting in the oxazoline N-attacked and the metal center-attacked compounds correspondingly. Using one of the metal center-attacked electrophiles, 2.3 was demonstrated to give high diastereoselectivity. Parallel to COE allylic C-H activation complex 3.1, the propene and allylbenzene allylic C-H activation products have also been synthesized. The subsequent functionalization attempts have been examined by treating with Brønsted acids, Lewis acids, electrophiles, nucleophiles, 1,3-dipolar reagents and reagents containing multiple bonds able to be inserted. Various related complexes have been obtained under these conditions, in which one of the azide insertion compounds reductively eliminates to give an allylic functionalization product stoichiometrically. 3.1 reacts with various primary alcohols to give the decarbonylation dihydride complex To{sup M}Rh(H){sub 2}CO (4.1). 4.1 shows catalytic reactivity for primary alcohol decarbonylation under a photolytic condition. Meanwhile, 2.2 has been found to be more reactive than 4.1 for catalytic alcohol decarbonylation under the same condition. Various complexes and primary alcohols have been investigated as well. The proposed mechanism is based on the stochiometric reactions of the possible metal and organic intermediates. Primary amines, hypothesized to undergo a similar reaction pathway, have been verified to give dehydrogenative coupling product, imines. In the end, the well-developed neutral tridentate Tpm coordinates to the rhodium bis(ethylene) dimer in the presence of TlPF{sub 6} to give the cationic complex, [TpmRh(C{sub 2}H{sub 4}){sub 2}][PF{sub 6}] (5.1). 5.1 serves as the first example of explicit determination of the solid state hapticity, evidenced by X-ray structure, among all the cationic Tpm{sup R}M(C{sub 2}H{sub 4}){sub 2}{sup +} (Tpm{sup R} = Tpm, Tpm*, M = Rh, Ir) derivatives. The substitution chemistry of this compound has been studied by treating with soft and hard donors. The trimethylphosphine-sbustituted complex activates molecular hydrogen to give the dihydride compound.

Ho, Hung-An

2012-03-06T23:59:59.000Z

11

Journal: Trevor Downey: Ecuador July 31, 2007  

E-Print Network (OSTI)

lake where we saw dolphins jump and swim through the crystal-clear water. The anaconda sunbathing and alligator spotting. On the boat trip back to the landing, we spotted a real anaconda sunbathing on a branch

Farritor, Shane

12

Rhodium Nanoparticle Shape Dependence in the Reduction of NO by CO  

SciTech Connect

The shape dependence of the catalytic reduction of NO by CO on Rhodium nanopolyhedra and nanocubes was studied from 230-270 C. The nanocubes are found to exhibit higher turnover frequency and lower activation energy than the nanopolyhedra. These trends are compared to previous studies on Rh single crystals.

Renzas, J.R.; Zhang, Y.; Huang, W.; Somorjai, G.A.

2009-07-13T23:59:59.000Z

13

Rhodium dihydride (RhH[subscript 2]) with high volumetric hydrogen density  

DOE Green Energy (OSTI)

Materials with very high hydrogen density have attracted considerable interest due to a range of motivations, including the search for chemically precompressed metallic hydrogen and hydrogen storage applications. Using high-pressure synchrotron X-ray diffraction technique and theoretical calculations, we have discovered a new rhodium dihydride (RhH{sub 2}) with high volumetric hydrogen density (163.7 g/L). Compressing rhodium in fluid hydrogen at ambient temperature, the fcc rhodium metal absorbs hydrogen and expands unit-cell volume by two discrete steps to form NaCl-typed fcc rhodium monohydride at 4 GPa and fluorite-typed fcc RhH{sub 2} at 8 GPa. RhH{sub 2} is the first dihydride discovered in the platinum group metals under high pressure. Our low-temperature experiments show that RhH{sub 2} is recoverable after releasing pressure cryogenically to 1 bar and is capable of retaining hydrogen up to 150 K for minutes and 77 K for an indefinite length of time.

Li, Bing; Ding, Yang; Kim, Duck Young; Ahuja, Rajeev; Zou, Guangtian; Mao, Ho-Kwang (Jilin); (Uppsala); (Cambridge); (CIW)

2012-03-14T23:59:59.000Z

14

Selective catalytic reduction system and process for treating NOx emissions using a palladium and rhodium or ruthenium catalyst  

Science Conference Proceedings (OSTI)

A process for the catalytic reduction of nitrogen oxides (NOx) in a gas stream (29) in the presence of H.sub.2 is provided. The process comprises contacting the gas stream with a catalyst system (38) comprising zirconia-silica washcoat particles (41), a pre-sulfated zirconia binder (44), and a catalyst combination (40) comprising palladium and at least one of rhodium, ruthenium, or a mixture of ruthenium and rhodium.

Sobolevskiy, Anatoly (Orlando, FL); Rossin, Joseph A. (Columbus, OH); Knapke, Michael J. (Columbus, OH)

2011-07-12T23:59:59.000Z

15

Faraday Discuss. Chem. SOC.,1989, 87, 337-344 Butane Hydrogenolysis over Single-crystal Rhodium Catalysts  

E-Print Network (OSTI)

Faraday Discuss. Chem. SOC.,1989, 87, 337-344 Butane Hydrogenolysis over Single-crystal Rhodium&M University, College Station, Texas 77843, U.S.A. Hydrogenolysis of n-butane has been studied over the (110 of surface composition and geometry.' For example, in our laboratories, the activity for ethane' and butane

Goodman, Wayne

16

Long-Term Testing of Rhodium-Based Catalysts for Mixed Alcohol Synthesis – 2013 Progress Report  

SciTech Connect

The U.S. Department of Energy’s Pacific Northwest National Laboratory has been conducting research since 2005 to develop a catalyst for the conversion of synthesis gas (carbon monoxide and hydrogen) into mixed alcohols for use in liquid transportation fuels. Initially, research involved screening possible catalysts based on a review of the literature, because at that time, there were no commercial catalysts available. The screening effort resulted in a decision to focus on catalysts containing rhodium and manganese. Subsequent research identified iridium as a key promoter for this catalyst system. Since then, research has continued to improve rhodium/manganese/iridium-based catalysts, optimizing the relative and total concentrations of the three metals, examining baseline catalysts on alternative supports, and examining effects of additional promoters. Testing was continued in FY 2013 to evaluate the performance and long-term stability of the best catalysts tested to date. Three tests were conducted. A long-term test of over 2300 hr duration at a single set of operating conditions was conducted with the best carbon-supported catalyst. A second test of about 650 hr duration at a single set of operating conditions was performed for comparison using the same catalyst formulation on an alternative carbon support. A third test of about 680 hr duration at a single set of operating conditions was performed using the best silica-supported catalyst tested to date.

Gerber, Mark A.; Gray, Michel J.; Thompson, Becky L.

2013-09-23T23:59:59.000Z

17

MERCURY-NITRITE-RHODIUM-RUTHENIUM INTERACTIONS IN NOBLE METAL CATALYZED HYDROGEN GENERATION FROM FORMIC ACID DURING NUCLEAR WASTE PROCESSING AT THE SAVANNAH RIVER SITE - 136C  

DOE Green Energy (OSTI)

Chemical pre-treatment of radioactive waste at the Savannah River Site is performed to prepare the waste for vitrification into a stable waste glass form. During pre-treatment, compounds in the waste become catalytically active. Mercury, rhodium, and palladium become active for nitrite destruction by formic acid, while rhodium and ruthenium become active for catalytic conversion of formic acid into hydrogen and carbon dioxide. Nitrite ion is present during the maximum activity of rhodium, but is consumed prior to the activation of ruthenium. Catalytic hydrogen generation during pre-treatment can exceed radiolytic hydrogen generation by several orders of magnitude. Palladium and mercury impact the maximum catalytic hydrogen generation rates of rhodium and ruthenium by altering the kinetics of nitrite ion decomposition. New data are presented that illustrate the interactions of these various species.

Koopman, D.; Pickenheim, B.; Lambert, D.; Newell, J; Stone, M.

2009-09-02T23:59:59.000Z

18

Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis -- 2011 Progress Report  

SciTech Connect

Pacific Northwest National Laboratory has been conducting research to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). In recent years, this research has primarily involved the further development of catalysts containing rhodium and manganese based on the results of earlier catalyst screening tests. Research during FY 2011 continued to examine the performance of RhMn catalysts on alternative supports including selected zeolite, silica, and carbon supports. Catalyst optimization continued using both the Davisil 645 and Merck Grade 7734 silica supports. Research also was initiated in FY 2011, using the both Davisil 645 silica and Hyperion CS-02C-063 carbon supports, to evaluate the potential for further improving catalyst performance, through the addition of one or two additional metals as promoters to the catalysts containing Rh, Mn, and Ir.

Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O.; Rummel, Becky L.

2011-10-01T23:59:59.000Z

19

Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis -- 2010 Progress Report  

SciTech Connect

Pacific Northwest National Laboratory has been conducting research for the U.S. Department of Energy, Energy Efficiency Renewable Energy, Biomass Program to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas. In recent years this research has primarily involved the further development of a silica-supported catalyst containing rhodium and manganese that was selected from earlier catalyst screening tests. A major effort during 2010 was to examine alternative catalyst supports to determine whether other supports, besides the Davisil 645 silica, would improve performance. Optimization of the Davisil 645 silica-supported catalyst also was continued with respect to candidate promoters iridium, platinum, and gallium, and examination of selected catalyst preparation and activation alternatives for the baseline RhMn/SiO2 catalyst.

Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O.; White, J. F.; Rummel, Becky L.; Stevens, Don J.

2010-10-01T23:59:59.000Z

20

Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis -- 2009 Progress Report  

DOE Green Energy (OSTI)

Pacific Northwest National Laboratory (PNNL) has been conducting research for the United States Department of Energy, Energy Efficiency Renewable Energy, Biomass Program to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). This research has involved the screening of potential catalysts, and optimization of the more promising ones, using laboratory scale reactors. During 2009, the main goal of the testing program focused on optimizing selected supported catalysts containing rhodium (Rh) and manganese (Mn). Optimization involved examining different total concentrations and atomic ratios of Rh and Mn as well as that of the more promising promoters (Ir and Li) identified in the earlier screening studies. Evaluation of catalyst performance focused on attaining improvements with respect to the space-time-yield and converted carbon selectivity to C2+ oxygenates, with additional consideration given to the fraction of the oxygenates that were C2+ alcohols.

Gerber, Mark A.; Gray, Michel J.; Stevens, Don J.; White, J. F.; Rummel, Becky L.

2010-12-21T23:59:59.000Z

Note: This page contains sample records for the topic "trevor houser rhodium" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis – 2012 Progress Report  

SciTech Connect

Pacific Northwest National Laboratory has been conducting research to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). In recent years, this research has primarily involved the further development of catalysts containing rhodium and manganese based on the results of earlier catalyst screening tests. Testing continued in FY 2012 to further improve the Ir-promoted RhMn catalysts on both silica and carbon supports for producing mixed oxygenates from synthesis gas. This testing re-examined selected alternative silica and carbon supports to follow up on some uncertainties in the results with previous test results. Additional tests were conducted to further optimize the total and relative concentrations of Rh, Mn, and Ir, and to examine selected promoters and promoter combinations based on earlier results. To establish optimum operating conditions, the effects of the process pressure and the feed gas composition also were evaluated.

Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O.; Thompson, Becky L.

2012-11-01T23:59:59.000Z

22

Catalytic partial oxidation of iso-octane over rhodium catalysts: An experimental, modeling, and simulation study  

Science Conference Proceedings (OSTI)

Catalytic partial oxidation of iso-octane over a rhodium/alumina coated honeycomb monolith is experimentally and numerically studied at short-contact times for varying fuel-to-oxygen ratios. A new experimental set-up with well-defined inlet and boundary conditions is presented. The conversion on the catalyst and in the gas-phase is modeled by detailed reaction mechanisms including 857 gas-phase and 17 adsorbed species. Elementary-step based heterogeneous and homogeneous reaction mechanisms are implemented into two-dimensional flow field description of a single monolith channel. Experiment and simulation provide new insights into the complex reaction network leading to varying product distribution as function of fuel-to-oxygen ratio. At fuel rich conditions, the formation of by-products that can serve as coke precursors is observed and interpreted. (author)

Hartmann, M.; Minh, H.D. [Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Maier, L. [Institute for Nuclear and Energy Technology, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Deutschmann, O. [Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Institute for Nuclear and Energy Technology, Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)

2010-09-15T23:59:59.000Z

23

Base-Catalyzed Insertion of Dioxygen into Rhodium-Hydrogen Bonds: Kinetics and Mechanism  

DOE Green Energy (OSTI)

The reaction between molecular oxygenm and rhodium hydrides L(OH)RhH{sup +} (L = (NH{sub 3}){sub 4}, trans-L{sup 1}, and cis-L{sup 1}, where L{sup 1} = cyclam) in basic aqueous solutions rapidly produces the corresponding hydroperoxo complexes. Over the pH range 8 < pH < 12, the kinetics exhibit a first order dependence on [OH{sup -}]. The dependence on [O{sub 2}] is less than first order and approaches saturation at the highest concentrations used. These data suggest an attack by OH{sup -} at the hydride with k = (1.45 {+-} 0.25) x 10{sup 3} M{sup -1} s{sup -1} for trans-L{sup 1}(OH)RhH{sup +} at 25 C, resulting in heterolytic cleavage of the Rh-H bond and formation of a reactive Rh(I) intermediate. A competition between O{sub 2} H{sub 2}O for Rh(I) is the source of the observed dependence on O{sub 2}.

Szajna-Fuller, Ewa; Bakac, Andreja

2009-10-27T23:59:59.000Z

24

Hydrogenation of CO and CO/sub 2/ on clean rhodium and iron foils. Correlations of reactivities and surface compositions  

DOE Green Energy (OSTI)

An experimental arrangement consisting of an ultrahigh vacuum bell jar equipped with an internal sample isolation cell was used to investigate the hydrogenation of CO over Fe and Rh surfaces. This apparatus permitted both UHV surface characterization (Auger electron spectroscopy, low-energy electron diffraction) and high pressure (1-20 atm) catalytic reactions to be carried out. Small surface area (approximately 1 cm/sup 2/) metal samples, both single crystals and polycrystalline foils, were used to catalyze the H/sub 2//CO reaction at high pressures (1-6 atm). Reaction products were monitored with a gas chromatograph equipped with a flame ionization detector. The surface compositions of the metal samples were determined before and after the reaction and the results correlated with the observed product distributions and reaction rates. In addition, the influence of various surface additives (carbon, oxygen, potassium) was also investigated. Iron was the more reactive of the two metals studied and was found to produce C/sub 1/-C/sub 5/ straight chain hydrocarbons but it poisoned rapidly. The catalytically active surface of both metals was covered with a carbonaceous monolayer. The carbonaceous monolayer was stable on the rhodium surface and produced C/sub 1/-C/sub 4/ hydrocarbons at a steady rate even after several hours of reaction. The absolute rates on rhodium samples were, however, substantially lower than those observed for the catalytically active iron samples. Differences in the poisoning characteristics and product distributions of the initially clean metal surfaces and the promoted rhodium and iron catalysts indicate the importance of additives and the formation of surface compounds in controlling the activity and selectivity.

Dwyer, D.; Yoshida, K.; Somorjai, G.A.

1977-12-16T23:59:59.000Z

25

Structural sensitivity studies of ethylene hydrogenation on platinum and rhodium surfaces  

DOE Green Energy (OSTI)

The catalytic hydrogenation of ethylene and hydrogen on the well characterized surfaces of the noble metals platinum and rhodium has been studied for the purposes of determining the relative activity of these two substrates as well as the degree of structure sensitivity. The Pt(111) and the Rh(755) single crystal surfaces,as well as Pt and Rh foils, were employed as substrates to study the effect of surface step structure on reactivity. In addition, vibrational spectroscopy studies were performed for ethylene adsorption on the stepped Rh(755) surface. The catalytic reaction were obtained using a combined ultrahigh vacuum chamber coupled with an atmospheric pressure reaction chamber that functioned as a batch reactor. Samples could be prepared using standard surface science techniques and characterized for surface composition and geometry using Auger Electron Spectroscopy and Low Energy Electron Diffraction. A comparison of the reactivity of Rh(111) with the results from this study on Rh(755) allows a direct determination of the effect of step structure on ethylene hydrogenation activity. Structure sensitivity is expected to exhibit orders of magnitude differences in rate as surface orientation is varied. In this case, no significant differences were found, confirming the structure insensitivity of this reaction over this metal. The turnover frequency of the Rh(111) surface, 5 {times} 10{sup 1} s{sup {minus}1}, is in relatively good agreement with the turnover frequency of 9 {times} 10{sup 1} s{sup {minus}1} measured for the Rh(755) surface. Rate measurements made on the Pt(111) surface and the Pt foil are in excellent agreement, both measuring 3 {times} 10{sup 2} s{sup minus}1. Likewise, it is concluded that no strong structure sensitivity for the platinum surfaces exists. High Resolution Electron Energy Loss Spectroscopy studies of adsorbed ethylene on the Rh(755) surface compare favorably with the ethylidyne spectra obtained on the Rh(111) and Rh(100) surfaces.

Quinlan, M.A. [California Univ., Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley National Lab., CA (United States)

1996-01-01T23:59:59.000Z

26

Kinetics and Mechanism of Hydrogen-Atom Abstraction from Rhodium Hydrides by Alkyl Radicals in Aqueous Solutions  

DOE Green Energy (OSTI)

The kinetics of the reaction of benzyl radicals with [L{sup 1}(H{sub 2}O)RhH{l_brace}D{r_brace}]{sup 2+} (L{sup 1}=1,4,8,11-tetraazacyclotetradecane) were studied directly by laser-flash photolysis. The rate constants for the two isotopologues, k=(9.3 {+-} 0.6) x 10{sup 7} M{sup -1} s{sup -1} (H) and (6.2 {+-} 0.3) x 10{sup 7} M{sup -1} s{sup -1} (D), lead to a kinetic isotope effect k{sub H}/k{sub D}=1.5 {+-} 0.1. The same value was obtained from the relative yields of PhCH{sub 3} and PhCH{sub 2}D in a reaction of benzyl radicals with a mixture of rhodium hydride and deuteride. Similarly, the reaction of methyl radicals with {l_brace}[L{sup 1}(H{sub 2}O)RhH]{sup 2+} + [L{sup 1}(H{sub 2}O)RhD]{sup 2+}{r_brace} produced a mixture of CH{sub 4} and CH{sub 3}D that yielded k{sub H}/k{sub D}=1.42 {+-} 0.07. The observed small normal isotope effects in both reactions are consistent with reduced sensitivity to isotopic substitution in very fast hydrogen-atom abstraction reactions. These data disprove a literature report claiming much slower kinetics and an inverse kinetic isotope effect for the reaction of methyl radicals with hydrides of L{sup 1}Rh.

Pestovsky, Oleg; Veysey, Stephen W.; Bakac, Andrej

2011-03-22T23:59:59.000Z

27

Rhodium Recovery from Spent Rhodium Plating Solutions  

Science Conference Proceedings (OSTI)

A Study on the Stress Test of Truck Frames for Freight Trains · A Study on the ... Defect Energetics and Fission Product Transport in ZrC · Deformation Field and ...

28

Rhodium self-powered neutron detector as a suitable on-line thermal neutron flux monitor in BNCT treatments  

Science Conference Proceedings (OSTI)

Purpose: A rhodium self-powered neutron detector (Rh SPND) has been specifically developed by the Comision Nacional de Energia Atomica (CNEA) of Argentina to measure locally and in real time thermal neutron fluxes in patients treated with boron neutron capture therapy (BNCT). In this work, the thermal and epithermal neutron response of the Rh SPND was evaluated by studying the detector response to two different reactor spectra. In addition, during clinical trials of the BNCT Project of the CNEA, on-line neutron flux measurements using the specially designed detector were assessed. Methods: The first calibration of the detector was done with the well-thermalized neutron spectrum of the CNEA RA-3 reactor thermal column. For this purpose, the reactor spectrum was approximated by a Maxwell-Boltzmann distribution in the thermal energy range. The second calibration was done at different positions along the central axis of a water-filled cylindrical phantom, placed in the mixed thermal-epithermal neutron beam of CNEA RA-6 reactor. In this latter case, the RA-6 neutron spectrum had been well characterized by both calculation and measurement, and it presented some marked differences with the ideal spectrum considered for SPND calibrations at RA-3. In addition, the RA-6 neutron spectrum varied with depth in the water phantom and thus the percentage of the epithermal contribution to the total neutron flux changed at each measurement location. Local (one point-position) and global (several points-positions) and thermal and mixed-field thermal neutron sensitivities were determined from these measurements. Thermal neutron flux was also measured during BNCT clinical trials within the irradiation fields incident on the patients. In order to achieve this, the detector was placed on patient's skin at dosimetric reference points for each one of the fields. System stability was adequate for this kind of measurement. Results: Local mixed-field thermal neutron sensitivities and global thermal and mixed-field thermal neutron sensitivities derived from measurements performed at the RA-6 were compared and no significant differences were found. Global RA-6-based thermal neutron sensitivity showed agreement with pure thermal neutron sensitivity measurements performed in the RA-3 spectrum. Additionally, the detector response proved nearly unchanged by differences in neutron spectra from real (RA-6 BNCT beam) and ideal (considered for calibration calculations at RA-3) neutron source descriptions. The results confirm that the special design of the Rh SPND can be considered as having a pure thermal response for neutron spectra with epithermal-to-thermal flux ratios up to 12%. In addition, the linear response of the detector to thermal flux allows the use of a mixed-field thermal neutron sensitivity of 1.95 {+-} 0.05 x 10{sup -21} A n{sup -1}{center_dot}cm{sup 2}{center_dot}s. This sensitivity can be used in spectra with up to 21% epithermal-to-thermal flux ratio without significant error due to epithermal neutron and gamma induced effects. The values of the measured fluxes in clinical applications had discrepancies with calculated results that were in the range of -25% to +30%, which shows the importance of a local on-line independent measurement as part of a treatment planning quality control system. Conclusions: The usefulness of the CNEA Rh SPND for the on-line local measurement of thermal neutron flux on BNCT patients has been demonstrated based on an appropriate neutron spectra calibration and clinical applications.

Miller, Marcelo E.; Sztejnberg, Manuel L.; Gonzalez, Sara J.; Thorp, Silvia I.; Longhino, Juan M.; Estryk, Guillermo [Comision Nacional de Energia Atomica, Av. del Libertador 8250, Ciudad de Buenos Aires 1429 (Argentina); Comision Nacional de Energia Atomica, Av. del Libertador 8250, Ciudad de Buenos Aires 1429, Argentina and CONICET, Av. Rivadavia 1917, Ciudad de Buenos Aires 1033 (Argentina); Comision Nacional de Energia Atomica, Av. del Libertador 8250, Ciudad de Buenos Aires 1429 (Argentina)

2011-12-15T23:59:59.000Z

29

Rhodium-Catalyzed C-C Bond Formation via Heteroatom-Directed C-H Bond Activation  

SciTech Connect

Once considered the 'holy grail' of organometallic chemistry, synthetically useful reactions employing C-H bond activation have increasingly been developed and applied to natural product and drug synthesis over the past decade. The ubiquity and relative low cost of hydrocarbons makes C-H bond functionalization an attractive alternative to classical C-C bond forming reactions such as cross-coupling, which require organohalides and organometallic reagents. In addition to providing an atom economical alternative to standard cross - coupling strategies, C-H bond functionalization also reduces the production of toxic by-products, thereby contributing to the growing field of reactions with decreased environmental impact. In the area of C-C bond forming reactions that proceed via a C-H activation mechanism, rhodium catalysts stand out for their functional group tolerance and wide range of synthetic utility. Over the course of the last decade, many Rh-catalyzed methods for heteroatom-directed C-H bond functionalization have been reported and will be the focus of this review. Material appearing in the literature prior to 2001 has been reviewed previously and will only be introduced as background when necessary. The synthesis of complex molecules from relatively simple precursors has long been a goal for many organic chemists. The ability to selectively functionalize a molecule with minimal pre-activation can streamline syntheses and expand the opportunities to explore the utility of complex molecules in areas ranging from the pharmaceutical industry to materials science. Indeed, the issue of selectivity is paramount in the development of all C-H bond functionalization methods. Several groups have developed elegant approaches towards achieving selectivity in molecules that possess many sterically and electronically similar C-H bonds. Many of these approaches are discussed in detail in the accompanying articles in this special issue of Chemical Reviews. One approach that has seen widespread success involves the use of a proximal heteroatom that serves as a directing group for the selective functionalization of a specific C-H bond. In a survey of examples of heteroatom-directed Rh catalysis, two mechanistically distinct reaction pathways are revealed. In one case, the heteroatom acts as a chelator to bind the Rh catalyst, facilitating reactivity at a proximal site. In this case, the formation of a five-membered metallacycle provides a favorable driving force in inducing reactivity at the desired location. In the other case, the heteroatom initially coordinates the Rh catalyst and then acts to stabilize the formation of a metal-carbon bond at a proximal site. A true test of the utility of a synthetic method is in its application to the synthesis of natural products or complex molecules. Several groups have demonstrated the applicability of C-H bond functionalization reactions towards complex molecule synthesis. Target-oriented synthesis provides a platform to test the effectiveness of a method in unique chemical and steric environments. In this respect, Rh-catalyzed methods for C-H bond functionalization stand out, with several syntheses being described in the literature that utilize C-H bond functionalization in a key step. These syntheses are highlighted following the discussion of the method they employ.

Colby, Denise; Bergman, Robert; Ellman, Jonathan

2010-05-13T23:59:59.000Z

30

I. Interaction of ammonia with single crystal rhodium catalysts. II. Hydrogen and nitrogen adsorption on a W(111) surface: a theoretical molecular orbital approach  

DOE Green Energy (OSTI)

Rates of ammonia decomposition on (110), (100), and (111) single crystal faces of rhodium were measured at 580 to 725/sup 0/K and 10/sup -3/ to 500 x 10/sup -3/ torr. The decomposition rates were proportional to P/sub NH/sub 3//sup/1/2/ and P/sub NH/sub 3// at low and high hydrogen pressures, respectively. The H/sub 2/ kinetic order varied from 0 (low P/sub H/sub 2//) to -1.0 (high P/sub H/). The rate was independent of N/sub 2/ pressure. NH/sub 3/ decomposes about 1.5 times faster than ND/sub 3/ on the (110) and (111) faces. Rates on the (110) surface are over 10 times as rapid as on the (111). LEED, Auger, and flash desorption experiments indicated that boron was a significant surface poison and that the Rh(110) surface was essentially nitrogen-free. A rate expression is derived from a model involving surface species Rh/sub 2/NH, RhH, and RhN on a nearly bare RH surface. The rate limiting process involves the concurrent dehydrogenation of Rh/sub 2/NH and desorption of N/sub 2/. A decreasing NH/sub 3/ order (< 1/2) at high P/sub NH/sub 3// and low T is due to buildup of surface intermediates. The relative bonding energies of hydrogen and nitrogen chemisorbed at three sites on a W(111) surface were obtained via the extended Hueckel molecular orbital theory. The preferred site for both H and N chemisorption was determined as the TOP position, i.e., a single coordination site on top of a protruding W atom. The W(111) surface was simulated by truncated arrays of seven tungsten atoms. The basis set for the calculations included the tungsten valence orbitals plus the filled 5p orbitals needed for repulsion at small internuclear distances. N adsorption in the three-fold holes available on the W(111) lattices used disrupted the W--W bonds sufficiently to cause the overall bond energy to be less than for the single coordination site. The dissymmetry between the three-fold lattices and the four-fold W d orbitals may also be a contributing factor.

Vavere, A.

1979-01-01T23:59:59.000Z

31

It's Elemental - Isotopes of the Element Rhodium  

NLE Websites -- All DOE Office Websites (Extended Search)

Isotopes Mass Number Half-life Decay Mode Branching Percentage 89 1.5 microseconds Electron Capture (suspected) No Data Available Proton Emission (suspected) No Data Available...

32

MEASUREMENTS OF THE 2001 APRIL 15 AND 2005 JANUARY 20 GROUND-LEVEL ENHANCEMENTS BY THE MILAGRO WATER CERENKOV  

E-Print Network (OSTI)

WATER CERENKOV DETECTOR BY Trevor Morgan B.S., University of New Hampshire (2004) DISSERTATION Submitted

California at Santa Cruz, University of

33

Monodisperse Platinum and Rhodium Nanoparticles as Model Heterogeneous Catalysts  

E-Print Network (OSTI)

R. Structure of Metallic Catalysts ; Academic Press: London,pretreatments of the Rh catalysts and analyzing thea Pt(octahedra)/SBA-15 catalyst increased from 0.01 to 28

Coble, Inger M

2008-01-01T23:59:59.000Z

34

Material synthesis and hydrogen storage of palladium-rhodium alloy.  

DOE Green Energy (OSTI)

Pd and Pd alloys are candidate material systems for Tr or H storage. We have actively engaged in material synthesis and studied the material science of hydrogen storage for Pd-Rh alloys. In collaboration with UC Davis, we successfully developed/optimized a supersonic gas atomization system, including its processing parameters, for Pd-Rh-based alloy powders. This optimized system and processing enable us to produce {le} 50-{mu}m powders with suitable metallurgical properties for H-storage R&D. In addition, we studied hydrogen absorption-desorption pressure-composition-temperature (PCT) behavior using these gas-atomized Pd-Rh alloy powders. The study shows that the pressure-composition-temperature (PCT) behavior of Pd-Rh alloys is strongly influenced by its metallurgy. The plateau pressure, slope, and H/metal capacity are highly dependent on alloy composition and its chemical distribution. For the gas-atomized Pd-10 wt% Rh, the absorption plateau pressure is relatively high and consistent. However, the absorption-desorption PCT exhibits a significant hysteresis loop that is not seen from the 30-nm nanopowders produced by chemical precipitation. In addition, we observed that the presence of hydrogen introduces strong lattice strain, plastic deformation, and dislocation networking that lead to material hardening, lattice distortions, and volume expansion. The above observations suggest that the H-induced dislocation networking is responsible for the hysteresis loop seen in the current atomized Pd-10 wt% Rh powders. This conclusion is consistent with the hypothesis suggested by Flanagan and others (Ref 1) that plastic deformation or dislocations control the hysteresis loop.

Lavernia, Enrique J. (University of California, Davis); Yang, Nancy Y. C.; Ong, Markus D. (Whithworth University, Spokane, WA)

2011-08-01T23:59:59.000Z

35

Recovery of Palladium and Rhodium from Spent Automobile ...  

Science Conference Proceedings (OSTI)

... group metals (PGM) and increases the effective contact area of the solid-liquid reaction. ... A Novel Vacuum Aluminothermic Reduction Lithium Process ... Effects of Lime Additions on the Sulphur Distribution between Red Mud Based Fluxes ...

36

Nuclear Magnetism and Superconductivity: Investigations on Lithium and Rhodium.  

E-Print Network (OSTI)

??This thesis describes low temperature experiments on lithium. The experiments concentrate on investigating low temperature phase transitions of two subsystems in this metal: its nuclear… (more)

Juntunen, Kirsi

2005-01-01T23:59:59.000Z

37

Nuclear magnetism and superconductivity : investigations on lithium and rhodium.  

E-Print Network (OSTI)

??This thesis describes low temperature experiments on lithium. The experiments concentrate on investigating low temperature phase transitions of two subsystems in this metal: its nuclear… (more)

Juntunen, Kirsi

2005-01-01T23:59:59.000Z

38

Microsoft Word - NEGTN02-#208578-v2-FINAL_2012_CASL_REVIEW_REPORT...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1 Office of Nuclear Energy Modeling and Simulation Energy Innovation Hub First Annual Review Report Thursday, August 18, 2011 Prepared By: Alex Larzelere, Trevor Cook , Ray...

39

Dissolution of Platinum,Palladium and Rhodium in 250g/l NaCl ...  

Science Conference Proceedings (OSTI)

Biosorption Characteristics of Pb(II) from Aqueous Solution onto Poplar Cotton · Characterization of Aluminum Cathode Sheets Used for Zinc Electrowinning.

40

Mechanistic studies of an unusual epoxide-forming elimination of a b-hydroxyalkyl rhodium porphyrin  

E-Print Network (OSTI)

acid-catalysis, and alternative hydrocarbon fuels through Fisher-Tropsch synthesis. The novel catalytic transportation fuels through Fisher-Tropsch synthesis." In a postdoctoral position at the University

Groves, John T.

Note: This page contains sample records for the topic "trevor houser rhodium" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


41

Transition metal oxides deposited on rhodium and platinum: Surface chemistry and catalysis  

DOE Green Energy (OSTI)

The surface chemistry and catalytic reactivity of transition metal oxides deposited on Rh and Pt substrates has been examined in order to establish the role of oxide-metal interactions in influencing catalytic activity. The oxides investigated included titanium oxide (TiOx), vanadium oxide (VOx), iron oxide (FeOx), zirconium oxide (ZrOx), niobium oxide (NbOx), tantalum oxide (TaOx), and tungsten oxide (WOx). The techniques used to characterize the sample included AES, XPS, LEED, TPD, ISS, and STM. After characterization of the surface in UHV, the sample was enclosed in an atmospheric reaction cell to measure the influence of the oxide deposits on the catalytic activity of the pure metal for CO and CO{sub 2} hydrogenation. The oxide deposits were found to strongly enhance the reactivity of the Rh foil. The rates of methane formation were promoted by up to 15 fold with the maximum in rate enhancement occurring at oxide coverages of approximately 0.5 ML. TiOx TaOx, and NbOx were the most effective promoters and were stable in the highest oxidation states during both reactions (compared to VOx, WOx, and FeOx). The trend in promoter effectiveness was attributed to the direct relationship between oxidation state and Lewis acidity. Bonding at the metal oxide/metal interface between the oxygen end of adsorbed CO and the Lewis acidic oxide was postulated to facilitate C-O bond dissociation and subsequent hydrogenation. 192 refs.

Boffa, A.B. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States). Materials Sciences Div.

1994-07-01T23:59:59.000Z

42

Evaluation of Promoters for Rhodium-Based Catalysts for Mixed Alcohol Synthesis  

DOE Green Energy (OSTI)

Pacific Northwest National Laboratory (PNNL) and National Renewable Energy Laboratory (NREL) are conducting research to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). PNNL is tasked with obtaining commercially-available catalysts or preparing promising mixed-alcohol catalysts and screening them in a laboratory-scale reactor system. Commercially-available catalysts and the most promising experimental catalysts are provided to NREL for testing using a slipstream from a pilot-scale biomass gasifier. A total of 28 tests were conducted to evaluate 22 different promoters as well as an unpromoted catalyst. The following general trends were observed for the test results: • The highest carbon selectivity to C2+ oxygenates occurred at the lowest reaction temperatures and accompanying lowest space time yields (STYs). • The lowest carbon selectivity to C2+ oxygenates occurred at the highest reaction temperatures because of high carbon conversion to hydrocarbons. • The highest C2+-oxygenate STYs occurred between 300°C and 325°C, with the gas hourly space velocity (GHSV) adjusted when necessary to maintain carbon conversion ranges between ~ 30 and 40 percent. Higher carbon selectivity to hydrocarbons at higher temperatures resulted in lower C2+-oxygenate STYs. • When catalysts were heated to between 300°C and 325°C the catalysts showed evidence of some deactivation with respect to C2+ oxygenate productivity, accompanied by reduced chain growth for the hydrocarbon products. The degree of deactivation and the temperature at which it occurred varied between the different catalysts tested. Of all of the catalysts evaluated, the Li-promoted catalysts had the highest carbon selectivity to C2+ oxygenates (47 percent) under the conditions at which the maximum C2+-oxygenate STYs were obtained.

Gerber, Mark A.; White, James F.; Gray, Michel J.; Stevens, Don J.

2008-12-08T23:59:59.000Z

43

Acetic Acid from the Carbonylation of Chloride Methane Over Rhodium Based Catalysts  

E-Print Network (OSTI)

on an indirect route via synthesis gas (syngas), i.e., methane is first con- verted to syngas before it is further transformed into other useful products [6]. However, the production of syngas from methane) 130:286­290 DOI 10.1007/s10562-009-0017-9 #12;[12], which is produced from syngas feedstock with Cu

Bao, Xinhe

44

It's Elemental - Isotopes of the Element Ruthenium  

NLE Websites -- All DOE Office Websites (Extended Search)

Technetium Previous Element (Technetium) The Periodic Table of Elements Next Element (Rhodium) Rhodium Isotopes of the Element Ruthenium Click for Main Data Most of the isotope...

45

It's Elemental - The Element Ruthenium  

NLE Websites -- All DOE Office Websites (Extended Search)

Technetium Previous Element (Technetium) The Periodic Table of Elements Next Element (Rhodium) Rhodium The Element Ruthenium Click for Isotope Data 44 Ru Ruthenium 101.07 Atomic...

46

The Legacy of Oil Spills  

E-Print Network (OSTI)

010-0527-5 The Legacy of Oil Spills J. T. Trevors & M. H.workers were killed, and oil has been gushing out everday. It is now June, and oil continues to spew forth into

Trevors, J. T.; Saier, M. H.

2010-01-01T23:59:59.000Z

47

ARM - News Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

the ship, and to see Mike Reynolds, who had just gotten off the ship and was flying back home. Trevor hasn't been to sea before, but he's traveled considerably. He had a job for a...

48

22nd Conference on Hydrology A Satellite View of Global Water and Energy Cycling  

E-Print Network (OSTI)

Water and Energy Cycling (2008 - 88Annual_22hydro) 2/6/2008http://ams.confex.com/ams/88Annual22nd Conference on Hydrology 8.1 A Satellite View of Global Water and Energy Cycling Paul R. Houser in modeling capability, satellite observations have great potential to make huge advances in water and energy

Houser, Paul R.

49

Rhodium Catalysts in the Oxidation of CO by O2 and NO: Shape, Composition, and Hot Electron Generation  

E-Print Network (OSTI)

ACTIVITY OF PLATINUM CATALYSTS. Journal of Catalysis 1966,SUPPORTED BIMETALLIC-CLUSTER CATALYSTS. Journal of Catalysisnanoparticle heterogeneous catalyst. Chem. Commun. 1999, (

Renzas, James Russell

2010-01-01T23:59:59.000Z

50

HYDROGENATION OF CO AND CO ON CLEAN RHODIUM AND IRON FOILS. CORRELATIONS OF REACTIVITIES AND SURFACE COMPOSITIONS  

E-Print Network (OSTI)

l) As a result of coal gasification (coal + H 0 + CO + H )data for the coal gasification and water shift reactionso

Dwyer, D.

2011-01-01T23:59:59.000Z

51

HYDROGENATION OF CO AND CO ON CLEAN RHODIUM AND IRON FOILS. CORRELATIONS OF REACTIVITIES AND SURFACE COMPOSITIONS  

E-Print Network (OSTI)

R. B. Anderson, The Fischer- Tropsch and Related Syntheses (carbons are called the Fischer-Tropsch reaction named afterwere produced by the Fischer-Tropsch reaction because of the

Dwyer, D.

2011-01-01T23:59:59.000Z

52

Rhodium Catalysts in the Oxidation of CO by O2 and NO: Shape, Composition, and Hot Electron Generation  

E-Print Network (OSTI)

Spectroscopy. Angewandte Chemie-International Edition 2008,Spectroscopy. Angewandte Chemie-International Edition 2008,Complex Physics? Angewandte Chemie-International Edition

Renzas, James Russell

2010-01-01T23:59:59.000Z

53

Publications by number 1. Synthesis of rhodium (II) pyrazolate complexes. Crystal structure of tetra-m-3,5-  

E-Print Network (OSTI)

was concentrated by ultrafiltration using an Amicon YM-10 cell membrane, buffer exchanged against 10% ACN and 0L by ultrafiltration using an Amicon stirred cell concentrator with a YM-10 membrane, and the buffer was exchanged evaporator to remove ACN, and then concentrated to 30 mL by ultrafiltration using an Amicon stirred cell

Alvarez, Pedro J.

54

Influence of Ceria and Nickel Addition to Alumina-Supported Rhodium Catalyst for Propane Steam Reforming at Low Temperatures.  

E-Print Network (OSTI)

??This work aims to develop a fundamental understanding of the catalyst composition-structure-activity relationships for propane steam reforming over supported Rh catalysts. The work investigates the… (more)

Li, Yan

2009-01-01T23:59:59.000Z

55

It's Elemental - The Periodic Table of Elements  

NLE Websites -- All DOE Office Websites (Extended Search)

Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine...

56

Tridentate Phosphine Linkers for Immobilized Catalysts: Development and Characterization of Immobilized Rhodium Complexes and Solid-State NMR Studies of Polymers  

E-Print Network (OSTI)

The major directions of this thesis involve (1) the synthesis, immobilization, and characterization of tridentate phosphine linkers on silica, (2) the study of unprecedented Si2C bond cleavage in Rh and Ir phosphine complexes, and (3) the study of performance polymers with solid2state NMR techniques. First a brief overview of solid2state NMR and its relevance to the various areas of chemistry covered in this thesis is given. Following the synthesis, immobilization, and characterization of tridentate phosphine ligands, EtOSi[(CH2)nPPh2]3 (n = 4, 7, 11) and [MeP((CH2)nPPh2)3]+I? (n = 4, 7, 11) on silica is detailed. Both, immobilization by electrostatic interactions and by a covalent siloxane bond to the support, is studied and compared. Ligand exchange with Wilkinson?s catalyst affords immobilized Rh complexes. These materials are applied to catalytic olefin hydrogenation. In either case active hydrogenation catalysts are obtained that can easily and efficiently be recycled up to 30 times. Detailed investigations reveal that irrespective of the linkage to the support the catalysts consist initially of well2defined molecular species that form supported Rh nanoparticles with a narrow size distribution in the course of the catalytic reaction. The nanoparticles are active hydrogenation catalysts as well, and no metal leaching into solution is detected. The reaction of the tridentate phosphine ligands EtOSi[(CH2)2PPh2]3 and MeSi[(CH2)2PPh2]3 with Rh and Ir complexes is investigated. This reaction does not lead to the anticipated Wilkinson2type complexes with the metal in the +I oxidation state, but instead to oxidative addition of the C(sp3)2Si bond to Rh or Ir centers to yield octahedral complexes with the metal in the +III oxidation state. These complexes are fully characterized by multinuclear NMR in solution and in the solid state. Preliminary density functional theory (DFT) calculations corroborate the preference for oxidative addition. Subsequently the study of performance thermoplastics which are important materials for the oil and gas industry is presented. The polymer morphology is studied by solid2state NMR techniques. Special attention is devoted to potential decomposition pathways at elevated temperatures for polyetheretherketone (PEEK) and polyphenylene sulfide (PPS) polymers. 13C CP/MAS (cross polarization with magic angle spinning) NMR and IR spectroscopy reveal that PEEK polymers show no detectable chemical change on the molecular level, while PPS polymers display signs of oxidation of the thioether group and branching via formation of ether, thioether, and biphenyl linkages. Furthermore, the water absorption of polybenzimidazole (PBI), polyetherketoneketone (PEKK), and their blend PEKK2PBI is studied. It is demonstrated that steam2treatment even at high temperatures and pressures does not cause chemical decomposition and that the changes, which are morphological in nature, are fully reversible.

Guenther, Johannes 1983-

2012-12-01T23:59:59.000Z

57

September/October 2007 Clovertales  

E-Print Network (OSTI)

. Gelman, Samuel D. George, Philip M. Georges, Sekou C. Georgescu, Cezar Gerace, Chelsea M. Gerard, Cory W, Graham R. Hampton, Clarice J. Han, Ji Sook Han, Jiami Han, Jun Hance, Frederick P. Handler, Ariela S L. Harris, Lisa M. Harris, Sarah Hartblay, Trevor A. Hartjen, Sarah A. Hartman, Chelsea E. Hartough

Goodman, Robert M.

58

September/October 2010 Clovertales  

E-Print Network (OSTI)

. Gelman, Samuel D. George, Philip M. Georges, Sekou C. Georgescu, Cezar Gerace, Chelsea M. Gerard, Cory W, Graham R. Hampton, Clarice J. Han, Ji Sook Han, Jiami Han, Jun Hance, Frederick P. Handler, Ariela S L. Harris, Lisa M. Harris, Sarah Hartblay, Trevor A. Hartjen, Sarah A. Hartman, Chelsea E. Hartough

Goodman, Robert M.

59

Dean's List Fall 2012 Harpur College of Arts and Sciences  

E-Print Network (OSTI)

. Gelman, Samuel D. George, Philip M. Georges, Sekou C. Georgescu, Cezar Gerace, Chelsea M. Gerard, Cory W, Graham R. Hampton, Clarice J. Han, Ji Sook Han, Jiami Han, Jun Hance, Frederick P. Handler, Ariela S L. Harris, Lisa M. Harris, Sarah Hartblay, Trevor A. Hartjen, Sarah A. Hartman, Chelsea E. Hartough

Zhang, Zhongfei "Mark"

60

CATALOG 20002001CATALOG 20002001 4 The University  

E-Print Network (OSTI)

. Gelman, Samuel D. George, Philip M. Georges, Sekou C. Georgescu, Cezar Gerace, Chelsea M. Gerard, Cory W, Graham R. Hampton, Clarice J. Han, Ji Sook Han, Jiami Han, Jun Hance, Frederick P. Handler, Ariela S L. Harris, Lisa M. Harris, Sarah Hartblay, Trevor A. Hartjen, Sarah A. Hartman, Chelsea E. Hartough

Rhode Island, University of

Note: This page contains sample records for the topic "trevor houser rhodium" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Thermal Plasma Torches for Metallurgical Applications  

Science Conference Proceedings (OSTI)

Different types of plasma torches including a high power steam plasma torch and .... Recovery of Palladium and Rhodium from Spent Automobile Catalysts by ...

62

Brookhaven National Laboratory Technology Marketing Summaries ...  

Wind Energy; Partners (27) Visual ... platinum-metal oxide composites can ... This ternary catalyst consisting of platinum and rhodium on carbon-supported tin dioxide ...

63

The research bench meets industry: New facility scales up production of  

NLE Websites -- All DOE Office Websites (Extended Search)

Video: Scenes from Argonne's Materials Engineering Research Facility Video: Scenes from Argonne's Materials Engineering Research Facility Scenes from Argonne's Materials Engineering Research Facility Experiments can keep researchers on their feet all day long. Process R&D chemist Kris Pupek moves between fume hoods in the Materials Engineering Research Facility's process research and development lab, while lab-mate Trevor Dzwiniel records data in his notebook. Experiments can keep researchers on their feet all day long. Process R&D chemist Kris Pupek moves between fume hoods in the Materials Engineering Research Facility's process research and development lab, while lab-mate Trevor Dzwiniel records data in his notebook. Argonne material engineer YoungHo Shin prepares a coin cell battery in a glovebox in the Materials Engineering Research Facility. Once it is prepared, the battery can be tested to determine the energy output characteristics of a cathode material for lithium-ion batteries.

64

Reforming of methane with carbon dioxide to synthesize gas over supported rhodium catalysts: II. A steady-state tracing analysis: Mechanistic aspects of the carbon and oxygen reaction pathways to form CO  

SciTech Connect

Steady-state tracing techniques have been applied to investigate mechanistic aspects of the CH{sub 4} reforming reaction over CO{sub 2} over Rh supported on yttria-stabilized zirconia (YSZ) and Al{sub 2}O{sub 3} as catalysts. It was found that the surface coverage of active carbon-containing species, which are found in the reaction pathway to CO formation, is of the order of 0.2 over the Rh/Al{sub 2}O{sub 3} catalyst, while it is very small ({theta}{sub c}, < 0.02) over Rh/YSZ. The surface coverage of active oxygen-containing species which lead to the formation of CO is found to be very small over both Rh/Al{sub 2}O{sub 3} and Rh/YSZ catalysts. However, over the Rh/YSZ catalyst it was found that there exists a large reservoir of lattice oxygen species of the carrier which interact reversibly with gaseous CO{sub 2} under reforming reaction conditions. A spillover of these lattice oxygen species onto the Rh surface seems to occur, contributing to the formation of CO and H{sub 2}O. This reaction route proceeds in parallel with the reforming reaction on the Rh surface. 27 refs., 12 figs.

Efstathiou, A.M.; Kladi, A.; Tsipouriari, V.A. [Univ. of Patras (Greece)] [and others

1996-01-01T23:59:59.000Z

65

The Synthesis of Novel Metal and Metal Oxide Nanoparticles with Applications Towards Catalysis  

E-Print Network (OSTI)

with the rhodium source [(COD)Rh(NCCH 3 ) 2 ]BF 4 , and theof the reactants [(COD)Rh(NCCH 3 ) 2 ] BF 4 , (Bu 4 N) 2 HPOThe rhodium precursor chosen was [(COD)RhCl] 2 (COD = 1,5-

McMurdo, Meredith Joanne

2010-01-01T23:59:59.000Z

66

Experimental investigation of burnup credit for safe transport, storage, and disposal of spent nuclear fuel.  

SciTech Connect

This report describes criticality benchmark experiments containing rhodium that were conducted as part of a Department of Energy Nuclear Energy Research Initiative project. Rhodium is an important fission product absorber. A capability to perform critical experiments with low-enriched uranium fuel was established as part of the project. Ten critical experiments, some containing rhodium and others without, were conducted. The experiments were performed in such a way that the effects of the rhodium could be accurately isolated. The use of the experimental results to test neutronics codes is demonstrated by example for two Monte Carlo codes. These comparisons indicate that the codes predict the behavior of the rhodium in the critical systems within the experimental uncertainties. The results from this project, coupled with the results of follow-on experiments that investigate other fission products, can be used to quantify and reduce the conservatism of spent nuclear fuel safety analyses while still providing the necessary level of safety.

Berry, Donald T.; Harms, Gary A.; Ford, John T.; Walker, Sharon Ann; Helmick, Paul H.; Pickard, Paul S.

2004-04-01T23:59:59.000Z

67

Research Highlight  

NLE Websites -- All DOE Office Websites (Extended Search)

Data from DOE Atmospheric Radiation Measurement Program Allows Evaluation Data from DOE Atmospheric Radiation Measurement Program Allows Evaluation of Surface Models Submitter: Robock, A., Rutgers University Area of Research: Surface Properties Working Group(s): Cloud Modeling Journal Reference: Robock, A., Luo, L., Wood, E. F., Wen, F., Mitchell, K. E., Houser, P. R., Schaake, J. C., Lohmann, D., Cosgrove, B., Sheffield, J., Duan, Q., Higgins, R. W., Pinker, R. T., Tarpley, J. D., Basara, J. D., Crawford, K. C., Evaluation of the North American Land Data Assimilation System over the Southern Great Plains during the warm season, J. Geophys. Res., 108(D22), 8846, doi:10.1029/2002JD003245, 2003 An example of the model discrepancies is shown in a comparison of monthly mean diurnal cycle data from July 1999 at the ARM Southern Great Plains

68

LBA Land Use and Land Cover Change Data Sets Released  

NLE Websites -- All DOE Office Websites (Extended Search)

four data sets from the Carbon four data sets from the Carbon Dynamics and Nutrient Dynamics science themes, components of the LBA-ECO Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). LBA-ECO CD-36 South American Land Data Assimilation System Atmospheric Forcing Data . Data set prepared by L.G.G. de Goncalves, W.J. Shuttleworth, D. Vila, E. Larroza, M.J. Bottino, D.L. Herdies, J.A. Aravequia, J.G. de Mattos, D.L. Toll, M. Rodell and P. Houser. This data set provides South American Land Data Assimilation System (SALDAS) atmospheric forcing data necessary for land surface modeling for South America. The data were derived by combining modeled and observation based sources.The forcing data cover the entire continent of South America at 0.125 degree resolution and are built around the model-calculated values of

69

Research Highlight  

NLE Websites -- All DOE Office Websites (Extended Search)

Critical Evaluation of the ICARUS Portion of the ISCCP Simulator Using ARM Critical Evaluation of the ICARUS Portion of the ISCCP Simulator Using ARM Data Download a printable PDF Submitter: Mace, G., Utah State University Area of Research: General Circulation and Single Column Models/Parameterizations Working Group(s): Cloud Life Cycle Journal Reference: Mace GG, S Houser, S Benson, SA Klein, and QL Min. 2011. "Critical evaluation of the ISCCP simulator using ground-based remote sensing data." Journal of Climate, 24(6), doi:10.1175/2010JCLI3517.1. Figure 1. Comparison of actual cloud top pressure from ARM remote sensors compared to ISCCP (top) and after the ICARUS algorithm has been used to convert the measured cloud top pressures to ISCCP-like quantities (bottom). Figure 2. Comparison of various measures of optical depth. Top left shows

70

Draft Minutes  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Meeting Meeting April 21, 2008 Crystal City Marriott Hotel Arlington, Virginia Committee Members Participating William Martin, Chair Brew Barron Daniel Ponemaan Thomas Cochran Burton Richter Michael Corradini Allen Sessoms Marvin Fertel Kunihiko Uematsu Susan Ion Committee Member Absent Neil Todreas Other Participants: John Boger, Designated Federal Official, Office of Nuclear Energy, USDOE Nancy Carder, Medical University of South Carolina, Support Staff Trevor Cook, Office of Nuclear Energy, USDOE Phillip Finck, Associate Director, Idaho National Laboratory Shane Johnson, Director, Office of Nuclear Energy, USDOE Paul Kearns, Battelle Memorial Institute Paul Lisowski, Deputy Assistant Secretary for Fuel Cycle Development, USDOE

71

Preparation of high specific activity technetium-96  

DOE Patents (OSTI)

The present invention relates to a method of producing Tc-96 from the proton irradiation of a rhodium target and a technique for isolating under remote hot cell conditions the Tc-96 from the proton irradiated target.

Mausner, Leonard F. (Stony Brook, NY); Srivastava, Suresh C. (Setauket, NY); Prach, Thomas (Port Jefferson, NY)

1992-01-01T23:59:59.000Z

72

Production of hydrogen from alcohols  

DOE Patents (OSTI)

A process for producing hydrogen from ethanol or other alcohols. The alcohol, optionally in combination with water, is contacted with a catalyst comprising rhodium. The overall process is preferably carried out under autothermal conditions.

Deluga, Gregg A. (St. Paul, MN); Schmidt, Lanny D. (Minneapolis, MN)

2007-08-14T23:59:59.000Z

73

TREC - 7 I nteractive T rack 11. September 1998 Topic ...  

Science Conference Proceedings (OSTI)

... 353i 1 mining prospection 353i 2 oil resources 353i 3 rhodium exploration 353i 4 ozone hole / upper atmosphere 353i 5 greenhouse effect 353i 6 ...

2003-08-20T23:59:59.000Z

74

Preparation of high specific activity technetium-96  

DOE Patents (OSTI)

The present invention relates to a method of producing Tc-96 from the proton irradiation of a rhodium target and a technique for isolating under remote hot cell conditions the Tc-96 from the proton irradiated target.

Mausner, L.F.; Srivastava, S.C.; Prach, T.

1990-12-31T23:59:59.000Z

75

Chemistry of Bimetallic Linked Cyclopentadienyl Complexes: Progress Report, 1 December 1986 --30 November 1989  

DOE R&D Accomplishments (OSTI)

Research continued on the chemistry and preparation of bimetallic cyclopentadienyl complexes containing up to two tungsten or one tungsten and a cobalt, rhodium, or ruthenium. The general method for preparation and analysis of polyenes is also discussed. (CBS)

Schrock, R. R.

1989-00-00T23:59:59.000Z

76

Inspection Report: INS-L-12-04 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

4 4 Inspection Report: INS-L-12-04 June 22, 2012 Alleged Procurement and Hiring Practice Irregularities within the Office of Policy and International Affairs The Office of Policy and International Affairs (PI) has primary responsibility for the Department of Energy's international energy activities including international emergency management, national security and international cooperation in science and technology. To accomplish its mission, PI has contracts with various subject matter experts such as Rhodium Group, LLC (Rhodium). Rhodium combines policy experience, quantitative economic tools and research to analyze global trends. The Rhodium contract, valued at approximately $992,000, was executed in September 2010, as a 2-year contract. The Office of Inspector General received a complaint alleging inappropriate

77

Cross-linking proteins with bimetallic tetracarboxylate compounds of transition metals  

DOE Patents (OSTI)

Stable cross-linked complexes of transition-metal tetracarboxylates and proteins are formed. The preferred transition-metal is rhodium. The protein may be collagen or an enzyme such as a proteolytic enzyme.

Kostic, Nenad M. (Ames, IA); Chen, Jian (Ames, IA)

1991-03-05T23:59:59.000Z

78

Thin film solar energy collector  

DOE Patents (OSTI)

A multi-layer solar energy collector of improved stability comprising: (1) a substrate of quartz, silicate glass, stainless steel or aluminum-containing ferritic alloy; (2) a solar absorptive layer comprising silver, copper oxide, rhodium/rhodium oxide and 0-15% by weight of platinum; (3) an interlayer comprising silver or silver/platinum; and (4) an optional external anti-reflective coating, plus a method for preparing a thermally stable multi-layered solar collector, in which the absorptive layer is undercoated with a thin film of silver or silver/platinum to obtain an improved conductor-dielectric tandem.

Aykan, Kamran (Monmouth Beach, NJ); Farrauto, Robert J. (Westfield, NJ); Jefferson, Clinton F. (Millburn, NJ); Lanam, Richard D. (Westfield, NJ)

1983-11-22T23:59:59.000Z

79

Microsoft Word - lois for 2011_v2.doc  

NLE Websites -- All DOE Office Websites (Extended Search)

Letters of Intent Letters of Intent 2011 Call for Beamline Development Proposals National Synchrotron Light Source II 1. High-energy x-ray micro-mapping of materials for advanced energy and structural engineering applications beamline (HEX) Spokesperson: Mark Croft, Rutgers University Source: Superconducting wiggler 2. Synchrotron-based discoveries for Chemical Biology (HIT) Marc Allaire, Brookhaven National Laboratory Undulator 3. NSLS-II Beamline for Combined High Magnetic Field and High Pressure Materials Studies (HMP) Trevor Tyson, New Jersey Institute of Technology Dipole wiggler 4. High-energy macromolecular crystallography (HMX) Vivian Stojanoff, Brookhaven National Laboratory 5. Monochromatic/White Beam X-ray Topography and High Resolution Diffraction Beamline at NSLS-II (HXT)

80

REAL-TIME BUILDING ENERGY SIMULATION USING ENERGYPLUS AND THE  

NLE Websites -- All DOE Office Websites (Extended Search)

REAL-TIME BUILDING ENERGY SIMULATION USING ENERGYPLUS AND THE REAL-TIME BUILDING ENERGY SIMULATION USING ENERGYPLUS AND THE BUILDING CONTROLS VIRTUAL TEST BED Xiufeng Pang 1 , Prajesh Bhattacharya 1 , Zheng O'Neill 2 , Philip Haves 1 , Michael Wetter 1 , and Trevor Bailey 2 1 Lawrence Berkeley National Laboratory, Berkeley, CA, USA 2 United Technologies Research Center, East Hartford, CT, USA ABSTRACT Most commercial buildings do not perform as well in practice as intended by the design and their performances often deteriorate over time. Reasons include faulty construction, malfunctioning equipment, incorrectly configured control systems and inappropriate operating procedures (Haves et al., 2001, Lee et al., 2007). To address this problem, the paper presents a simulation-based whole building performance monitoring tool that allows a

Note: This page contains sample records for the topic "trevor houser rhodium" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Renewable Energy Finance Workshop  

Open Energy Info (EERE)

Agenda - December 10 Agenda - December 10 th , 2012 Renewable Energy Finance Workshop 12:00 - 12:15 WELCOME AND INTRODUCTIONS- Richard Kauffman 12:15 - 12:25 PRESIDENTIAL PRIORITIES - Jon Powers & Rick Duke 12:25 - 12:35 INDUSTRY OVERVIEW - Lisa Jacobson & John Stanton Presentation of common themes and emerging trends from industry members. 12:35 - 1:00 MAJOR BARRIERS TO SECURITIZATION - Richard Kauffman & Trevor D'Olier-Lees Facilitated discussion on barriers to renewable energy deployment, such as data and standardized contracts. 1:00 - 1:20 BREAK 1:20 - 2:00 DATA AND RENEWABLE ENERGY RESOURCES - Ian Kalin & Chris Lohmann Open data, tools and programs that seek to support renewable energy financing. 2:00-2:20 BREAK

82

ARM - Blog Article  

NLE Websites -- All DOE Office Websites (Extended Search)

24, 2013 [Blog, Field Notes, MAGIC] 24, 2013 [Blog, Field Notes, MAGIC] An "Uneventful" Leg During MAGIC Bookmark and Share Editor's note: Ernie Lewis, principal investigator for the Marine ARM GPCI Investigations of Clouds (MAGIC) field campaign, sent this update on July 11, 2013. Thursday, July 11, evening We are just pulling into port in Honolulu (about 8pm local time on Thursday), a day later than normal, but we had left Los Angeles a day later than normal also. The trip was mostly uneventful (only one power outage), which is a good thing; typically anything that would make a trip "eventful" is not desirable. The instruments worked well, the techs-Pat and Mark-and, Trevor -a grad student-have been fun to work with, and the food was excellent. It was overcast nearly the entire way. It was bright a few times

83

Gas Phase Moleculer Dynamics (GPMD) Group | Chemistry Department |  

NLE Websites -- All DOE Office Websites (Extended Search)

Group Members Group Members Greg Hall (Group Leader) Chemical dynamics of unimolecular and bimolecular reactions. High resolution spectroscopic probes of collisional energy transfer processes. Elastic and inelastic interactions responsible for pressure broadening, saturation relaxation and depolarization. Non-adiabatic reactions and multiple surface interactions. Vector correlations and angular momentum polarization probes of chemical dynamics. Applied laser spectroscopy. Trevor Sears (PI) Use of frequency comb techniques for precision spectroscopic measurements in chemical systems. Development of new high resolution and high sensitivity spectroscopic techniques. Free radical spectroscopy relevant to combustion chemistry. Characterization of collisional phenomena and their effects on spectroscopic lineshapes, pressure broadening and sub-Doppler measurements. Hyperfine spectroscopy of 207PbF for potential e-EDM measurements

84

Slide 1  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Peer Review 2009 Peer Review 2009 Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin company, for the Untied State Department of Energy under contract DE-AC04-94AL85000. Joseph A. Henfling, Stan Atcitty, Frank Maldonado, Sandia National Laboratories Randy Normann, PermaWorks Nicholas Summers, Trevor Thornton, ASU SAND Number: 2009-5722C Overview * Program Goals for HT Power Controller - Ultimately a single module solution * Power Controller Design Details - PWM options (Microcontroller, FPGA) - High side gate control - HT MESFET demonstrated to drive SiC JFET in low side applications * Test Results * Future work * Conclusions Project Goals * Design HT power controller that can be integrated into a single module - Benefits include:

85

METAL COMPOSITIONS  

DOE Patents (OSTI)

Alloys of uranium which are strong, hard, and machinable are presented, These alloys of uranium contain bctween 0.1 to 5.0% by weight of at least one noble metal such as rhodium, palladium, and gold. The alloys may be heat treated to obtain a product with iniproved tensile and compression strengths,

Seybolt, A.U.

1959-02-01T23:59:59.000Z

86

Selectivity of the reactions of oxygenates on transition metal surfaces  

Science Conference Proceedings (OSTI)

The goal of this research has been to understand, by means of surface science studies, the elementary processes involved in the synthesis of higher oxygenates on transition metals, and the dependence of these processes upon the nature of the surface. We have completed a considerable body of work (Ph.D. thesis of J. Lynn Davis, 1988) on the reactions of alcohols, aldehydes, and carboxylic acids on clean and oxygen-containing Pd(111) surfaces. Work during the past year has focused on the surface chemistry of rhodium. We find both interesting similarities and differences between rhodium and palladium. Comparison of the two sheds light on common reaction networks among the transition metals, and on the differences between them which permit control of selectivities in catalytic reactions.

Barteau, M.A.

1989-01-01T23:59:59.000Z

87

Formation of thin-film resistors on silicon substrates  

DOE Patents (OSTI)

The formation of thin-film resistors by the ion implantation of a metallic conductive layer in the surface of a layer of phosphosilicate glass or borophosphosilicate glass which is deposited on a silicon substrate. The metallic conductive layer materials comprise one of the group consisting of tantalum, ruthenium, rhodium, platinum and chromium silicide. The resistor is formed and annealed prior to deposition of metal, e.g. aluminum, on the substrate.

Schnable, George L. (Montgomery County, PA); Wu, Chung P. (Hamilton Township, Mercer County, NJ)

1988-11-01T23:59:59.000Z

88

Model for the Prediction of the Hydriding Thermodynamics of Pd-Rh-Co Ternary Alloys  

DOE Green Energy (OSTI)

A dilute solution model (with respect to the substitutional alloying elements) has been developed, which accurately predicts the hydride formation and decomposition thermodynamics and the storage capacities of dilute ternary Pd-Rh-Co alloys. The effect of varying the rhodium and cobalt compositions on the thermodynamics of hydride formation and decomposition and hydrogen capacity of several palladium-rhodium-cobalt ternary alloys has been investigated using pressure-composition (PC) isotherms. Alloying in the dilute regime (<10 at.%) causes the enthalpy for hydride formation to linearly decrease with increasing alloying content. Cobalt has a stronger effect on the reduction in enthalpy than rhodium for equivalent alloying amounts. Also, cobalt reduces the hydrogen storage capacity with increasing alloying content. The plateau thermodynamics are strongly linked to the lattice parameters of the alloys. A near-linear dependence of the enthalpy of hydride formation on the lattice parameter was observed for both the binary Pd-Rh and Pd-Co alloys, as well as for the ternary Pd-Rh-Co alloys. The Pd-5Rh-3Co (at. %) alloy was found to have similar plateau thermodynamics as a Pd-10Rh alloy, however, this ternary alloy had a diminished hydrogen storage capacity relative to Pd-10Rh.

Teter, D.F.; Thoma, D.J.

1999-03-01T23:59:59.000Z

89

Strong Bond Activation with Late Transition-Metal Pincer Complexes as a Foundation for Potential Catalysis  

E-Print Network (OSTI)

Strong bond activation mediated by pincer ligated transiton-metal complexes has been the subject of intense study in recent years, due to its potential involvement in catalytic transformations. This dissertation has focused on the net heterolytic cleavage of B-H and B-B bonds across the N-Pd bond in a cationic (PNP)Pd fragment, the C-H oxidative addition to a (PNP)Ir center and the recent results on the C-H and C-O oxidative addition in reactions of aryl carboxylates with the (PNP)Rh fragment. Transition metal carbene and carbyne complexes are of great interest because of their role in a wide variety of catalytic reactions. Our work has resulted in the isolation of a rhodium(I) difluorocarbene. Reaction of the rhodium difluorocarbene complex with a silylium salt led to the C-F bond cleavage and the formation of a terminal fluorocarbyne complex. Reductive elimination is a critical step of cross coupling reactions. In order to examine the effect of the pincer ligand on the reductive elimination reactions from Rh(III), the first pi-accepting PNP ligand bearing pyrrolyl substituents was prepared and installed onto the rhodium center. Arylhalide (halide = Br, I) oxidative addition was achieved in the presence of donor ligands such as acetonitrile to form stable six-coordinate Rh(III) compounds. The C-O reductive elimination reactions in this system were also explored.

Zhu, Yanjun

2012-05-01T23:59:59.000Z

90

Heath Middle School Science Students Study Environmental Issue at Paducah  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Heath Middle School Science Students Study Environmental Issue at Heath Middle School Science Students Study Environmental Issue at Paducah Site Heath Middle School Science Students Study Environmental Issue at Paducah Site April 1, 2012 - 12:00pm Addthis Mentor Jim Erickson of the LATA Kentucky team shows Heath Middle School sixthgrader Ian Morgan how to use red cabbage to indicate if a watery solution is acidic, basic, or neutral. Mentor Jim Erickson of the LATA Kentucky team shows Heath Middle School sixthgrader Ian Morgan how to use red cabbage to indicate if a watery solution is acidic, basic, or neutral. Heath Middle School eighth-grader Travis Crouch performs a pH (acidity-basicity) test using red cabbage. Heath Middle School eighth-grader Travis Crouch performs a pH (acidity-basicity) test using red cabbage. Kelly Layne of the LATA Kentucky team tells Heath Middle School students how to use zinc pennies in an experiment with differing known and unknown solutions. Facing, from left, are students Atherton Milford, McKenzie Moss, Trevor Kendall, Max Kolb, and James Michael Dodd.

91

Real-time Building Energy Simulation using EnergyPlus and the Building  

NLE Websites -- All DOE Office Websites (Extended Search)

Real-time Building Energy Simulation using EnergyPlus and the Building Real-time Building Energy Simulation using EnergyPlus and the Building Controls Virtual Test Bed Title Real-time Building Energy Simulation using EnergyPlus and the Building Controls Virtual Test Bed Publication Type Conference Proceedings LBNL Report Number LBNL-5390E Year of Publication 2011 Authors Pang, Xiufeng, Prajesh Bhattacharya, Zheng O'Neill, Philip Haves, Michael Wetter, and Trevor Bailey Conference Name Proc. of the 12th IBPSA Conference Pagination p. 2890-2896 Date Published 11/2011 Conference Location Sydney, Australia Abstract Most commercial buildings do not perform as well in practice as intended by the design and their performances often deteriorate over time. Reasons include faulty construction, malfunctioning equipment, incorrectly configured control systems and inappropriate operating procedures (Haves et al., 2001, Lee et al., 2007). To address this problem, the paper presents a simulation-based whole building performance monitoring tool that allows a comparison of building actual performance and expected performance in real time. The tool continuously acquires relevant building model input variables from existing Energy Management and Control System (EMCS). It then reports expected energy consumption as simulated of EnergyPlus. The Building Control Virtual Test Bed (BCVTB) is used as the software platform to provide data linkage between the EMCS, an EnergyPlus model, and a database. This paper describes the integrated real-time simulation environment. A proof-of-concept demonstration is also presented in the paper.

92

Pollution prevention and waste minimization in metal finishing  

SciTech Connect

This study was done to identify pollution prevention and waste minimization opportunities in the general plating department and the printed circuit board processing department. Recommendations for certain recycle and recovery technologies were mad in order to reduce usage of acids and the volume of heavy metal sludge that is formed at the industrial Wastewater Pretreatment Facility (IWPF). Some of these technologies discussed were acid purification, electrowinning, and ion exchange. Specific technologies are prescribed for specific processes. Those plating processes where the metals can be recovered are copper, nickel, gold, cadmium, tin, lead, and rhodium.

Stimetz, C.J.

1994-12-01T23:59:59.000Z

93

Light induced electron transfer reactions of metal complexes  

DOE Green Energy (OSTI)

Properties of the excited states of tris(2,2'-bipyridine) and tris(1,10-phenanthroline) complexes of chromium(III), iron(II), ruthenium(II), osmium(II), rhodium(III), and iridium(III) are described. The electron transfer reactions of the ground and excited states are discussed and interpreted in terms of the driving force for the reaction and the distortions of the excited states relative to the corresponding ground states. General considerations relevant to the conversion of light into chemical energy are presented and progress in the use of polypyridine complexes to effect the light decomposition of water into hydrogen and oxygen is reviewed.

Sutin, N; Creutz, C

1980-01-01T23:59:59.000Z

94

Carbon aerogel electrodes for direct energy conversion  

DOE Patents (OSTI)

A direct energy conversion device, such as a fuel cell, using carbon aerogel electrodes, wherein the carbon aerogel is loaded with a noble catalyst, such as platinum or rhodium and soaked with phosphoric acid, for example. A separator is located between the electrodes, which are placed in a cylinder having plate current collectors positioned adjacent the electrodes and connected to a power supply, and a pair of gas manifolds, containing hydrogen and oxygen positioned adjacent the current collectors. Due to the high surface area and excellent electrical conductivity of carbon aerogels, the problems relative to high polarization resistance of carbon composite electrodes conventionally used in fuel cells are overcome.

Mayer, Steven T. (San Leandro, CA); Kaschmitter, James L. (Pleasanton, CA); Pekala, Richard W. (Pleasant Hill, CA)

1997-01-01T23:59:59.000Z

95

Carbon aerogel electrodes for direct energy conversion  

DOE Patents (OSTI)

A direct energy conversion device, such as a fuel cell, using carbon aerogel electrodes is described, wherein the carbon aerogel is loaded with a noble catalyst, such as platinum or rhodium and soaked with phosphoric acid, for example. A separator is located between the electrodes, which are placed in a cylinder having plate current collectors positioned adjacent the electrodes and connected to a power supply, and a pair of gas manifolds, containing hydrogen and oxygen positioned adjacent the current collectors. Due to the high surface area and excellent electrical conductivity of carbon aerogels, the problems relative to high polarization resistance of carbon composite electrodes conventionally used in fuel cells are overcome. 1 fig.

Mayer, S.T.; Kaschmitter, J.L.; Pekala, R.W.

1997-02-11T23:59:59.000Z

96

Method and system for ethanol production  

DOE Patents (OSTI)

A transition metal carbonyl and a tertiary amine are employed as a homogeneous catalytic system in methanol or a less volatile solvent to react methanol with carbon monoxide and hydrogen gas producing ethanol and carbon dioxide. The gas contains a high carbon monoxide to hydrogen ratio as is present in a typical gasifier product. The reaction has potential for anhydrous ethanol production as carbon dioxide rather than water is produced. Selected transition metal carbonyls include those of iron, rhodium ruthenium, manganese in combination with iron and possibly osmium. Selected amines include trimethylamine, N-Methylpyrrolidine, 2,4-diazabicyclooctane, dimethylneopentylamine, N-methylpiperidine and derivatives of N-methylpiperidine.

Feder, Harold M. (Darien, IL); Chen, Michael J. (Darien, IL)

1983-01-01T23:59:59.000Z

97

Method and system for ethanol production  

DOE Patents (OSTI)

A transition metal carbonyl and a tertiary amine are employed as a homogeneous catalytic system in methanol or a less volatile solvent to react methanol with carbon monoxide and hydrogen gas producing ethanol and carbon dioxide. The gas contains a high carbon monoxide to hydrogen ratio as is present in a typical gasifier product. The reaction has potential for anhydrous ethanol production as carbon dioxide rather than water is produced. Selected transition metal carbonyls include those of iron, rhodium, ruthenium, manganese in combination with iron and possibly osmium. Selected amines include trimethylamine, N-Methylpyrrolidine, 2,4-diazabicyclooctane, dimethylneopentylamine, N-methylpiperidine and derivatives of N-methylpiperidine.

Feder, H.M.; Chen, M.J.

1981-09-24T23:59:59.000Z

98

Summary report on four Oak Ridge sensors for enhancing nuclear safeguards neutron detectors  

SciTech Connect

The need for monitoring weapons grade Pu in nuclear facilities worldwide was addressed with four radiation detector technologies being developed at Y-12 and ORNL. This paper describes experimental results of 4 Oak Ridge Sensors for Enhancing Nuclear Safeguards (ORSENS) neutron detector technologies and includes the potential application, cost, and advantages for each. These are a {sup 6}LiF- ZnS(Ag) thermal neutron scintillator coupled to a wavelength-shifting optical fiber, a CdWO{sub 4} based scintillating thermal neutron detector, a rhodium silicon thermal neutron detector, and a proton- recoil fast neutron detector.

Williams, J.A.; Clark, R.L.; Hutchinson, D.P.; Miller, V.C.; Ramsey, J.A. [Oak Ridge National Lab., TN (United States); Bell, Z.W.; Hiller, J.M.; Wallace, S.A. [Oak Ridge Y-12 Plant, TN (United States)

1997-08-01T23:59:59.000Z

99

Multizone catalytic reforming process  

Science Conference Proceedings (OSTI)

This patent describes a process for the catalytic reforming of hydrocarbons comprising contacting the hydrocarbon feed in two sequential catalyst zones. It comprises: a first catalyst zone contains a first catalytic composite consisting essentially of a platinum component, a germanium component, a refractory inorganic oxide, and a halogen component; and a second catalyst zone contains a second catalytic composite comprising a platinum component, a germanium component, a refractory inorganic oxide, a halogen component, and catalytically effective amounts of a metal promoter selected from rhenium, rhodium, ruthenium, cobalt, nickel, and iridium, and mixtures thereof.

Moser, M.C.; Lawson, R.J.; Antos, G.J.; Wang, L.; Parulekar, V.N.

1990-05-29T23:59:59.000Z

100

Compatibility of aluminide-coated Hastelloy x and Inconel 617 in a simulated gas-cooled reactor environment  

Science Conference Proceedings (OSTI)

Commercially prepared aluminide coatings on Hastelloy X and Inconel 617 substrates were exposed to controlled-impurity helium at 850/sup 0/ and 950/sup 0/C for 3000 h. Optical and scanning electron (SEM) microscopy, electron microprobe profiles, and SEM X-ray mapping were used to evaluate and compare exposed and unexposed control samples. Four coatings were evaluated: aluminide, aluminide with platinum, aluminide with chromium, and aluminide with rhodium. With extended time at elevated temperature, nickel diffused into the aluminide coatings to form epsilon-phase (Ni/sub 3/Al). This diffusion was the primary cause of porosity formation at the aluminide/alloy interface.

Chin, J.; Johnson, W. R.; Chen, K.

1982-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "trevor houser rhodium" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Mixed Alcohol Synthesis Catalyst Screening  

DOE Green Energy (OSTI)

National Renewable Energy Laboratory (NREL) and Pacific Northwest National Laboratory (PNNL) are conducting research to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). PNNL is tasked with obtaining commercially available or preparing promising mixed-alcohol catalysts and screening them in a laboratory-scale reactor system. Commercially available catalysts and the most promising experimental catalysts are provided to NREL for testing using a slipstream from a pilot-scale biomass gasifier. From the standpoint of producing C2+ alcohols as the major product, it appears that the rhodium catalyst is the best choice in terms of both selectivity and space-time yield (STY). However, unless the rhodium catalyst can be improved to provide minimally acceptable STYs for commercial operation, mixed alcohol synthesis will involve significant production of other liquid coproducts. The modified Fischer-Tropsch catalyst shows the most promise for providing both an acceptable selectivity to C2+ alcohols and total liquid STY. However, further optimization of the Fischer-Tropsch catalysts to improve selectivity to higher alcohols is highly desired. Selection of a preferred catalyst will likely entail a decision on the preferred coproduct slate. No other catalysts tested appear amenable to the significant improvements needed for acceptable STYs.

Gerber, Mark A.; White, James F.; Stevens, Don J.

2007-09-03T23:59:59.000Z

102

Chemical Hydrogen Storage Using Polyhedral Borane Anions and Aluminum-Ammonia-Borane Complexes  

DOE Green Energy (OSTI)

Phase 1. Hydrolysis of borohydride compounds offer the potential for significant hydrogen storage capacity, but most work to date has focused on one particular anion, BH4-, which requires high pH for stability. Other borohydride compounds, in particular polyhedral borane anions offer comparable hydrogen storage capacity without requiring high pH media and their long term thermal and hydrolytic stability coupled with non-toxic nature make them a very attractive alternative to NaBH4. The University of Missouri project provided the overall program focal point for the investigation of catalytic hydrolysis of polyhedral borane anions for hydrogen release. Due to their inherent stability, a transition metal catalyst was necessary for the hydrolysis of polyhedral borane anions. Transition metal ions such as cobalt, nickel, palladium and rhodium were investigated for their catalytic activity in the hydrolysis of nido-KB11H14, closo-K2B10H10, and closo-K2B12H12. The rate of hydrolysis follows first-order kinetics with respect to the concentration of the polyhedral borane anion and surface area of the rhodium catalyst. The rate of hydrolysis depends upon a) choice of polyhedral borane anion, c) concentration of polyhedral borane anion, d) surface area of the rhodium catalyst and e) temperature of the reaction. In all cases the yield of hydrogen was 100% which corresponds to ~7 wt% of hydrogen (based on material wt%). Phase 2. The phase 2 of program at the University of Missouri was focused upon developing aluminum ammonia-boranes (Al-AB) as chemical hydrogen storage materials, specifically their synthesis and studies of their dehydrogenation. The ammonia borane molecule (AB) is a demonstrated source of chemically stored hydrogen (19.6 wt%) which meets DOE performance parameters except for its regeneration from spent AB and elemental hydrogen. The presence of an aluminum center bonded to multiple AB residues might combine the efficiency of AB dehydrogenation with an aluminum mediated hydrogenation process leading to reversibility. The Al-AB complexes have comparable hydrogen capacity with other M-AB and have potential to meet DOE’s 2010 and 2015 targets for system wt%.

Hawthorne, M. Frederick; Jalisatgi, Satish S.; Safronov, Alexander V.; Lee, Han Beak; Wu, Jianguo

2010-10-01T23:59:59.000Z

103

Microsoft Word - FujitaPubs12-18-06.htm  

NLE Websites -- All DOE Office Websites (Extended Search)

on 12/18/2006 2:12 PM on 12/18/2006 2:12 PM List of Publications: Etsuko Fujita 1. Carbon Dioxide Reduction by Pincer Rhodium η 2 -Dihydrogen Complexes: Hydrogen Binding Modes and Mechanistic Studies by Density Functional Theory Calculations. K.-W. Huang, J. H. Han, C. B. Musgrave, and E. Fujita, Organometallics, accepted. 2. Reaction of NH 3 with Titania: N-doping of the Oxide and TiN formation. H. Chen, A. Nambu, W. Wen, J. Graciani, Z. Zhong, J. C. Hanson, E. Fujita, and J. A. Rodríguez, J. Phys. Chem. B, accepted. 3. Direct Measurements of Rate Constants and Activation Volumes for the Binding of H 2 , D 2 , N 2 , C 2 H 4 and CH 3 CN to W(CO) 3 (PCy 3 ) 2 : Theoretical and Experimental Studies with Time-Resolved Step-Scan FTIR and UV-vis Spectroscopy. D. C. Grills,

104

Coming up with platinum substitutes may be elemental  

NLE Websites -- All DOE Office Websites (Extended Search)

Coming up with platinum substitutes may be elemental Coming up with platinum substitutes may be elemental Community Connections: Our link to Northern New Mexico Communities Latest Issue:Dec. 2013 - Jan. 2014 All Issues » submit Coming up with platinum substitutes may be elemental Lab researchers are working with an abundant element to take their place: cobalt. February 1, 2013 dummy image Read our archives. Contacts Editor Linda Anderman Email Community Programs Office Kurt Steinhaus Email Initial findings by a Los Alamos team indicate that if a cobalt atom is captured within a complex molecule, it can mimic the reactivity of platinum group metals. Platinum and some related precious metals (palladium, iridium, rhodium and ruthenium) are frequently used as chemical catalysts and for countless laboratory processes. As rare metals, they are also expensive. To ensure

105

NIDC: Online Catalog of Isotope Products | Product Search  

NLE Websites -- All DOE Office Websites (Extended Search)

Product Search Product Search Step 1 - Enter your search criteria below. Element Name Actinium Aluminum Americium Antimony Argon Arsenic Astatine Barium Berkelium Beryllium Bismuth Bohrium Boron Bromine Cadmium Caesium Calcium Californium Carbon Cerium Chlorine Chromium Cobalt Copernicium Copper Curium Darmstadtium Dubnium Dysprosium Einsteinium Erbium Europium Fermium Fluorine Francium Gadolinium Gallium Germanium Gold Hafnium Hassium Helium Holmium Hydrogen Indium Iodine Iridium Iron Krypton Lanthanum Lawrencium Lead Lithium Lutetium Magnesium Manganese Meitnerium Mendelevium Mercury Molybdenum Neodymium Neon Neptunium Nickel Niobium Nitrogen Nobelium Osmium Oxygen Palladium Phosphorus Platinum Plutonium Polonium Potassium Praseodymium Promethium Protactinium Radium Radon Rhenium Rhodium Roentgenium Rubidium Ruthenium Rutherfordium Samarium Scandium Seaborgium Selenium Silicon Silver Sodium Strontium Sulfur Tantalum Technetium Tellurium Terbium Thallium Thorium Thulium Tin Titanium Tungsten Ununhexium Ununoctium Ununpentium Ununquadium Ununseptium Ununtrium Uranium Vanadium Xenon Ytterbium Yttrium Zinc Zirconium

106

NIDC: Online Catalog of Isotope Products | Request a New Product  

NLE Websites -- All DOE Office Websites (Extended Search)

Request a New Product Request a New Product Step 1 - Enter the new product's criteria below. Element Name Actinium Aluminum Americium Antimony Argon Arsenic Astatine Barium Berkelium Beryllium Bismuth Bohrium Boron Bromine Cadmium Caesium Calcium Californium Carbon Cerium Chlorine Chromium Cobalt Copernicium Copper Curium Darmstadtium Dubnium Dysprosium Einsteinium Erbium Europium Fermium Fluorine Francium Gadolinium Gallium Germanium Gold Hafnium Hassium Helium Holmium Hydrogen Indium Iodine Iridium Iron Krypton Lanthanum Lawrencium Lead Lithium Lutetium Magnesium Manganese Meitnerium Mendelevium Mercury Molybdenum Neodymium Neon Neptunium Nickel Niobium Nitrogen Nobelium Osmium Oxygen Palladium Phosphorus Platinum Plutonium Polonium Potassium Praseodymium Promethium Protactinium Radium Radon Rhenium Rhodium Roentgenium Rubidium Ruthenium Rutherfordium Samarium Scandium Seaborgium Selenium Silicon Silver Sodium Strontium Sulfur Tantalum Technetium Tellurium Terbium Thallium Thorium Thulium Tin Titanium Tungsten Ununhexium Ununoctium Ununpentium Ununquadium Ununseptium Ununtrium Uranium Vanadium Xenon Ytterbium Yttrium Zinc Zirconium

107

A Novel Nanobio Catalyst for Biofuels | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

Multiple Crystal Cavities for Unlimited X-ray Energy Resolution and Multiple Crystal Cavities for Unlimited X-ray Energy Resolution and Coherence An Intriguing Twist in the Structure of a Cobalt Oxide Catalyst Breaking Records in Neurological Microradiology Exposing Valence-Bond Model Inadequacies Plants' Rapid Response System Revealed Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed A Novel Nanobio Catalyst for Biofuels AUGUST 27, 2012 Bookmark and Share Core shell nanoparticle inside Apo. Nanoparticles synthesized from noble metals such as ruthenium, rhodium, palladium, silver (Ag), osmium, iridium, platinum, and gold (Au) are attracting increased attention by researchers around the world looking for

108

Ray tracing flux calculation for the small and wide angle x-ray scattering diffraction station at the SESAME synchrotron radiation facility  

SciTech Connect

The calculation for the optics of the synchrotron radiation small and wide angle x-ray scattering beamline, currently under construction at SESAME is described. This beamline is based on a cylindrically bent germanium (111) single crystal with an asymmetric cut of 10.5 deg., followed by a 1.2 m long rhodium coated plane mirror bent into a cylindrical form. The focusing properties of bent asymmetrically cut crystals have not yet been studied in depth. The present paper is devoted to study of a particular application of a bent asymmetrically cut crystal using ray tracing simulations with the SHADOW code. These simulations show that photon fluxes of order of 1.09x10{sup 11} photons/s will be available at the experimental focus at 8.79 keV. The focused beam dimensions will be 2.2 mm horizontal full width at half maximum (FWHM) by 0.12 mm vertical (FWHM).

Salah, Wa'el [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan); Department of Physics, The Hashemite University, Zarqa 13115 (Jordan); Sanchez del Rio, M. [European Synchrotron Radiation Facility, Bp 220, 38043 Grenoble Cedex (France); Hoorani, H. [Synchrotron-light for Experimental Science and Application in the Middle East (SESAME), P.O. Box 7, Allan 19252 (Jordan)

2009-09-15T23:59:59.000Z

109

The CAESAR project: Experimental and modeling investigations of methane reforming in a CAtalytically Enhanced Solar Absorption Receiver on a parabolic dish  

DOE Green Energy (OSTI)

A joint US/Federal Republic of Germany (FRG) project has successfully tested a unique solar-driven chemical reactor in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) experiment. The CAESAR test was a {open_quotes}proof-of-concept{close_quotes} demonstration of carbon-dioxide reforming of methane in a commercial-scale, solar, volumetric receiver/reactor on a parabolic dish concentrator. The CAESAR design; test facility and instrumentation; thermal and chemical tests; and analysis of test results are presented in detail. Numerical models for the absorber and the receiver are developed and predicted performance is compared with test data. Post test analyses to assess the structural condition of the absorber and the effectiveness of the rhodium catalyst are presented. Unresolved technical issues are identified and future development efforts are recommended.

Muir, J.F.; Hogan, R.E. Jr.; Skocypec, R.D. [Sandia National Labs., Albuquerque, NM (US); Buck, R. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt, Stuttgart (DE). Inst. of Technical Thermodynamics

1993-07-01T23:59:59.000Z

110

Lightweight, durable lead-acid batteries  

Science Conference Proceedings (OSTI)

A lightweight, durable lead-acid battery is disclosed. Alternative electrode materials and configurations are used to reduce weight, to increase material utilization and to extend service life. The electrode can include a current collector having a buffer layer in contact with the current collector and an electrochemically active material in contact with the buffer layer. In one form, the buffer layer includes a carbide, and the current collector includes carbon fibers having the buffer layer. The buffer layer can include a carbide and/or a noble metal selected from of gold, silver, tantalum, platinum, palladium and rhodium. When the electrode is to be used in a lead-acid battery, the electrochemically active material is selected from metallic lead (for a negative electrode) or lead peroxide (for a positive electrode).

Lara-Curzio, Edgar (Lenoir City, TN); An, Ke (Knoxville, TX); Kiggans, Jr., James O. (Oak Ridge, TN); Dudney, Nancy J. (Knoxville, TN); Contescu, Cristian I. (Knoxville, TN); Baker, Frederick S. (Oak Ridge, TN); Armstrong, Beth L. (Clinton, TN)

2011-09-13T23:59:59.000Z

111

Lightweight, durable lead-acid batteries  

DOE Patents (OSTI)

A lightweight, durable lead-acid battery is disclosed. Alternative electrode materials and configurations are used to reduce weight, to increase material utilization and to extend service life. The electrode can include a current collector having a buffer layer in contact with the current collector and an electrochemically active material in contact with the buffer layer. In one form, the buffer layer includes a carbide, and the current collector includes carbon fibers having the buffer layer. The buffer layer can include a carbide and/or a noble metal selected from of gold, silver, tantalum, platinum, palladium and rhodium. When the electrode is to be used in a lead-acid battery, the electrochemically active material is selected from metallic lead (for a negative electrode) or lead peroxide (for a positive electrode).

Lara-Curzio, Edgar; An, Ke; Kiggans, Jr., James O; Dudney, Nancy J; Contescu, Cristian I; Baker, Frederick S; Armstrong, Beth L

2013-05-21T23:59:59.000Z

112

Surface science and heterogeneous catalysis  

DOE Green Energy (OSTI)

The catalytic reactions studied include hydrocarbon conversion over platinum, the transition metal-catalyzed hydrogenation of carbon monoxide, and the photocatalyzed dissociation of water over oxide surfaces. The method of combined surface science and catalytic studies is similar to those used in synthetic organic chemistry. The single-crystal models for the working catalyst are compared with real catalysts by comparing the rates of cyclopropane ring opening on platinum and the hydrogenation of carbon monoxide on rhodium single crystal surface with those on practical commercial catalyst systems. Excellent agreement was obtained for these reactions. This document reviews what was learned about heterogeneous catalysis from these surface science approaches over the past 15 years and present models of the active catalyst surface.

Somorjai, G.A.

1980-05-01T23:59:59.000Z

113

Refractory electrodes for joule heating and methods of using same  

DOE Patents (OSTI)

A certain group of electrically conductive refractory materials presently known for use in high temperature applications as throat constructions, melter sidewalls, forehearth, stacks, port sills, hot face lining for slagging coal gasifiers, slag runners, and linings for nuclear waste encapsulation furnaces may be used as electrodes permitting joule heating at temperatures in excess of 1200 C. in excess of about 4400 hours even in the presence of transition group element(s). More specifically, the invention is an electrode for melting earthen materials, wherein the electrode is made from an electrically conductive refractory material, specifically at least one metal oxide wherein the metal is selected from the group consisting of chrome, ruthenium, rhodium, tin and combinations thereof.

Lamar, David A. (West Richland, WA); Chapman, Chris C. (Richland, WA); Elliott, Michael L. (Kennewick, WA)

1998-01-01T23:59:59.000Z

114

Progress in chemical processing of LEU targets for {sup 99}Mo production -- 1997  

SciTech Connect

Presented here are recent experimental results of the continuing development activities associated with converting current processes for producing fission-product {sup 99}Mo from targets using high-enriched uranium (HEU) to low-enriched uranium (LEU). Studies were focused in four areas: (1) measuring the chemical behavior of iodine, rhodium, and silver in the LEU-modified Cintichem process, (2) performing experiments and calculations to assess the suitability of zinc fission barriers for LEU metal foil targets, (3) developing an actinide separations method for measuring alpha contamination of the purified {sup 99}Mo product, and (4) developing a cooperation with Sandia National Laboratories and Los Alamos National Laboratory that will lead to approval by the US Federal Drug Administration for production of {sup 99}Mo from LEU targets. Experimental results continue to show the technical feasibility of converting current HEU processes to LEU.

Vandegrift, G.F.; Conner, C.; Sedlet, J.; Wygmans, D.G. [Argonne National Lab., IL (United States); Wu, D. [Univ. of Illinois, Urbana, IL (United States); Iskander, F.; Landsberger, S. [Univ. of Texas, Austin, TX (United States)

1997-10-01T23:59:59.000Z

115

Method for fabricating beryllium-based multilayer structures  

SciTech Connect

Beryllium-based multilayer structures and a process for fabricating beryllium-based multilayer mirrors, useful in the wavelength region greater than the beryllium K-edge (111 .ANG. or 11.1 nm). The process includes alternating sputter deposition of beryllium and a metal, typically from the fifth row of the periodic table, such as niobium (Nb), molybdenum (Mo), ruthenium (Ru), and rhodium (Rh). The process includes not only the method of sputtering the materials, but the industrial hygiene controls for safe handling of beryllium. The mirrors made in accordance with the process may be utilized in soft x-ray and extreme-ultraviolet projection lithography, which requires mirrors of high reflectivity (>60%) for x-rays in the range of 60-140 .ANG. (60-14.0 nm).

Skulina, Kenneth M. (Livermore, CA); Bionta, Richard M. (Livermore, CA); Makowiecki, Daniel M. (Livermore, CA); Alford, Craig S. (Tracy, CA)

2003-02-18T23:59:59.000Z

116

SPONTANEOUS CATALYTIC WET AIR OXIDATION DURING PRE-TREATMENT OF HIGH-LEVEL RADIOACTIVE WASTE SLUDGE  

DOE Green Energy (OSTI)

Savannah River Remediation, LLC (SRR) operates the Defense Waste Processing Facility for the U.S. Department of Energy at the Savannah River Site. This facility immobilizes high-level radioactive waste through vitrification following chemical pretreatment. Catalytic destruction of formate and oxalate ions to carbon dioxide has been observed during qualification testing of non-radioactive analog systems. Carbon dioxide production greatly exceeded hydrogen production, indicating the occurrence of a process other than the catalytic decomposition of formic acid. Statistical modeling was used to relate the new reaction chemistry to partial catalytic wet air oxidation of both formate and oxalate ions driven by the low concentrations of palladium, rhodium, and/or ruthenium in the waste. Variations in process conditions led to increases or decreases in the total oxidative destruction, as well as partially shifting the preferred species undergoing destruction from oxalate ion to formate ion.

Koopman, D.; Herman, C.; Pareizs, J.; Bannochie, C.; Best, D.; Bibler, N.; Fellinger, T.

2009-10-01T23:59:59.000Z

117

Engineering and manufacturing of ITER first mirror mock-ups  

SciTech Connect

Most of the ITER optical diagnostics aiming at viewing and monitoring plasma facing components will use in-vessel metallic mirrors. These mirrors will be exposed to a severe plasma environment and lead to an important tradeoff on their design and manufacturing. As a consequence, investigations are carried out on diagnostic mirrors toward the development of optimal and reliable solutions. The goals are to assess the manufacturing feasibility of the mirror coatings, evaluate the manufacturing capability and associated performances for the mirrors cooling and polishing, and finally determine the costs and delivery time of the first prototypes with a diameter of 200 and 500 mm. Three kinds of ITER candidate mock-ups are being designed and manufactured: rhodium films on stainless steel substrate, molybdenum on TZM substrate, and silver films on stainless steel substrate. The status of the project is presented in this paper.

Joanny, M.; Travere, J. M.; Salasca, S.; Corre, Y. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Marot, L. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Thellier, C.; Gallay, G.; Cammarata, C.; Passier, B.; Ferme, J. J. [SESO, 305 Rue Louis Armand CS 30504, 13593 Aix-en-Provence Cedex 3 (France)

2010-10-15T23:59:59.000Z

118

Elimination Of Catalytic Hydrogen Generation In Defense Waste Processing Facility Slurries  

Science Conference Proceedings (OSTI)

Based on lab-scale simulations of Defense Waste Processing Facility (DWPF) slurry chemistry, the addition of sodium nitrite and sodium hydroxide to waste slurries at concentrations sufficient to take the aqueous phase into the alkaline region (pH > 7) with approximately 500 mg nitrite ion/kg slurry (assuming essential components to catalytic hydrogen generation) than the two primary process vessels. Rhodium certainly, and ruthenium likely, are present as metal-ligand complexes that are favored under certain concentrations of the surrounding species. Therefore, in the SMECT or RCT, where a small volume of SRAT or SME material would be significantly diluted, conditions would be less optimal for forming or sustaining the catalytic ligand species. Such conditions are likely to adversely impact the ability of the transferred mass to produce hydrogen at the same rate (per unit mass SRAT or SME slurry) as in the SRAT or SME vessels.

Koopman, D. C.

2013-01-22T23:59:59.000Z

119

Multizone catalytic reforming process  

Science Conference Proceedings (OSTI)

This patent describes a process for the catalytic reforming of hydrocarbons comprising contacting the hydrocarbon feed in two sequential catalyst zones. It comprises: an initial catalyst zone which is a fixed-bed system and contains an initial catalytic composite comprising a platinum component, a germanium component, a refractory inorganic oxide, and a halogen component; and a terminal catalyst zone which is a moving-bed system with associated continuous catalyst regeneration and contains a terminal catalytic composite having the essential absence of germanium and comprising a platinum component, a refractory inorganic oxide, a halogen component, and catalytically effective amounts of a metal promoter selected from one or more of the rhenium, tin, indium, rhodium, ruthenium, cobalt, nickel, and iridium.

Moser, M.; Lawson, R.J.; Wang, L.; Parulekar, V.; Peer, R.L.; Hamlin, C.R.

1991-01-15T23:59:59.000Z

120

Categorical Exclusion Determination Form Proposed Action Title: (0674-1610) TVN Systems, Inc. -  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

610) TVN Systems, Inc. - 610) TVN Systems, Inc. - Hydrogen/Bromine Electrical Energy Storage System Program or Field Office :Advanced Research Projects Agency - Energy (ARPA-E) Submit by E-mail LocationCs) CCity/County/State): TVN Systems, Inc. (Lawrence, KS); Vanderbilt University (Nashville, TN); University of Kansas (Lawrence, KS) Proposed Action Description: Funding will support efforts to develop a cost-effective hydrogen-bromine flow battery that utilizes advanced membrane materials, unique catalysts, a novel shunt current protection system , and advanced cell and system designs. Proposed work will consist of: (1) synthesizing active and stable Rhodium-sulfer based electro-catalytic materials for hydrogen reactions; (2) fabricating and testing nanofiber composite membranes;

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121

Colloid Science of Metal Nanoparticle Catalysts in 2D and 3D Structures. Challenges of Nucleation, Growth, Composition, Particle Shape, Size Control and their Influence on Activity and Selectivity  

SciTech Connect

Recent breakthroughs in synthesis in nanosciences have achieved control of size and shapes of nanoparticles that are relevant for catalyst design. In this article, we review the advance of synthesis of nanoparticles, fabrication of two and three dimensional model catalyst system, characterization, and studies of activity and selectivity. The ability to synthesize monodispersed platinum and rhodium nanoparticles in the 1-10 nm range permitted us to study the influence of composition, structure, and dynamic properties of monodispersed metal nanoparticle on chemical reactivity and selectivity. We review the importance of size and shape of nanoparticles to determine the reaction selectivity in multi-path reactions. The influence of metal-support interaction has been studied by probing the hot electron flows through the metal-oxide interface in catalytic nanodiodes. Novel designs of nanoparticle catalytic systems are discussed.

Somorjai, Gabor A.; Park, Jeong Y.

2008-02-13T23:59:59.000Z

122

Outlooks of HLW Partitioning Technologies Usage for Recovering of Platinum Metals from Spent Fuel  

Science Conference Proceedings (OSTI)

The existing practice of management of high level waste (HLW) generated by NPPs, call for a task of selective separation of the most dangerous long-lived radionuclides with the purpose of their subsequent immobilization and disposal. HLW partitioning allows to reduce substantially the cost of vitrified product storage owing to isolation of the most dangerous radionuclides, such as transplutonium elements (TPE) into separate fractions of small volumes, intended for ultimate storage. By now numerous investigations on partitioning of HLW of various composition have been carried out in many countries and a lot of processes permitting to recover cesium, strontium, TPE and rare earth elements (REE) have been already tested. Apart from enumerated radionuclides, a fair quantity of palladium and rhodium presents in spent fuel, but the problem of these elements recovery has not yet been decided at the operating radiochemical plants. A negative effect of platinum group metals (PGM) occurrence is determined by the formation of separate metal phase, which not only worsens the conditions of glass-melting but also shortens considerably the service life of the equipment. At the same time, the exhaustion of PGMs natural resources may finally lead to such a growth of their costs that the spent nuclear fuel would became a substituting source of these elements industrial production. Allowing above mentioned, it is of interest to develop the technique for ''reactor'' palladium and rhodium recovery process which would be compatible with HLW partitioning and could be realized using the same facilities. In the report the data on platinum metals distribution in spent fuel reprocessing products and the several flowsheets for palladium separation from HLW are presented.

Pokhitonov, Y. A.; Estimantovskiy, V.; Romanovski, v.; Zatsev, B.; Todd, T.

2003-02-24T23:59:59.000Z

123

Final Technical Report "Catalytic Hydrogenation of Carbon Monoxide and Olefin Oxidation" Grant number : DE-FG02-86ER13615  

SciTech Connect

Title: Catalytic Hydrogenation of Carbon Monoxide and Olefin Oxidation Grant No. DE-FG02-86ER13615 PI: Wayland, B. B. (wayland@sas.upenn.edu) Abstract Development of new mechanistic strategies and catalyst materials for activation of CO, H2, CH4, C2H4, O2, and related substrates relevant to the conversion of carbon monoxide, alkanes, and alkenes to organic oxygenates are central objectives encompassed by this program. Design and synthesis of metal complexes that manifest reactivity patterns associated with potential pathways for the hydrogenation of carbon monoxide through metallo-formyl (M-CHO), dimetal ketone (M-C(O)-M), and dimetal dionyl (M-C(O)-C(O)-M) species is one major focus. Hydrocarbon oxidation using molecular oxygen is a central goal for methane activation and functionalization as well as regioselective oxidation of olefins. Discovery of new reactivity patterns and control of selectivity are pursued through designing new metal complexes and adjusting reaction conditions. Variation of reaction media promotes distinct reaction pathways that control both reaction rates and selectivities. Dimetalloradical diporphyrin complexes preorganize transition states for substrate reactions that involve two metal centers and manifest large rate increases over mono-metalloradical reactions of hydrogen, methane, and other small molecule substrates. Another broad goal and recurring theme of this program is to contribute to the thermodynamic database for a wide scope of organo-metal transformations in a range of reaction media. One of the most complete descriptions of equilibrium thermodynamics for organometallic reactions in water and methanol is emerging from the study of rhodium porphyrin substrate reactions in aqueous and alcoholic media. Water soluble group nine metalloporphyrins manifest remarkably versatile substrate reactivity in aqueous and alcoholic media which includes producing rhodium formyl (Rh-CHO) and hydroxy methyl (Rh-CH2OH) species. Exploratory directions for this program include expending new strategies for anti-Markovnikov addition of water, alcohols, and amines with olefins, developing catalytic reactions of CO to give formamides and formic esters, and evaluating the potential for coupling reactions of CO to produce organic building blocks.

Wayland, B.B.

2009-08-31T23:59:59.000Z

124

Mixed Alcohol Synthesis Catalyst Screening 2007 Progress Report  

DOE Green Energy (OSTI)

Pacific Northwest National Laboratory (PNNL) and National Renewable Energy Laboratory (NREL) are researching the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). PNNL is obtaining commercially available mixed alcohol or preparing promising mixed-alcohol catalysts and screening them in a laboratory-scale reactor system. The most promising catalysts are provided to NREL for testing using a slipstream from a pilot-scale biomass gasifier. After a review of the literature in 2006 and conversations with companies that produce catalysts, it was determined that no commercial mixed-alcohol synthesis catalysts were available. One manufacturer supplied a modified methanol catalyst that was tested in the PNNL laboratory-scale system and provided to NREL for further testing. PNNL also prepared and tested the behavior of 10 other catalysts representing the distinct catalyst classes for mixed alcohol syntheses. Based on those results,testing in 2007 focused on the performance of the rhodium-based catalysts. The effects of adding promoters to the rhodium catalysts in addition to the manganese already being used were examined. The iron and rhenium promoters both stood out as achieving higher carbon selectivities , followed by Cu. Iridium and Li, on the other hand, had low carbon selectivity ratios of 0.27 and 0.22, respectively. Although testing of candidate promoters is not complete, it appears that Ir and Li promoters warrant further optimization and possibly combination to further improve STYs and carbon selectivities to C2+ oxygenates. However, using these promoters, it will be necessary to incorporate a separate hydrogenation catalyst to improve the yield of C2+ alcohols with respect to the other oxygenates. Fe, Re, and Cu stand out as possible candidates in this respect, but additional research is needed to examine whether they can be combined with the other promoters on the Rh-based catalyst or need to be optimized on a separate catalyst support that is either physically mixed or used in series with the promoted Rh-based catalyst.

Gerber, Mark A.; White, J. F.; Gray, Michel J.; Stevens, Don J.

2007-11-01T23:59:59.000Z

125

Noble metal catalyzed hydrogen generation from formic acid in nitrite-containing simulated nuclear waste media  

SciTech Connect

Simulants for the Hanford Waste Vitrification Plant (HWVP) feed containing the major non-radioactive components Al, Cd, Fe, Mn, Nd, Ni, Si, Zr, Na, CO{sub 3}{sup 2{minus}}, NO{sub 3}-, and NO{sub 2}- were used as media to evaluate the stability of formic acid towards hydrogen evolution by the reaction HCO{sub 2}H {yields} H{sub 2} + CO{sub 2} catalyzed by the noble metals Ru, Rh, and/or Pd found in significant quantities in uranium fission products. Small scale experiments using 40-50 mL of feed simulant in closed glass reactors (250-550 mL total volume) at 80-100{degree}C were used to study the effect of nitrite and nitrate ion on the catalytic activities of the noble metals for formic acid decomposition. Reactions were monitored using gas chromatography to analyze the CO{sub 2}, H{sub 2}, NO, and N{sub 2}O in the gas phase as a function of time. Rhodium, which was introduced as soluble RhCl{sub 3}{center_dot}3H{sub 2}O, was found to be the most active catalyst for hydrogen generation from formic acid above {approx}80{degree}C in the presence of nitrite ion in accord with earlier observations. The inherent homogeneous nature of the nitrite-promoted Rh-catalyzed formic acid decomposition is suggested by the approximate pseudo first-order dependence of the hydrogen production rate on Rh concentration. Titration of the typical feed simulants containing carbonate and nitrite with formic acid in the presence of rhodium at the reaction temperature ({approx}90{degree}C) indicates that the nitrite-promoted Rh-catalyzed decomposition of formic acid occurs only after formic acid has reacted with all of the carbonate and nitrite present to form CO{sub 2} and NO/N{sub 2}O, respectively. The catalytic activities of Ru and Pd towards hydrogen generation from formic acid are quite different than those of Rh in that they are inhibited rather than promoted by the presence of nitrite ion.

King, R.B.; Bhattacharyya, N.K. [Univ. of Georgia, Athens, GA (United States). Department of Chemistry; Wiemers, K.D.

1994-08-01T23:59:59.000Z

126

It's Elemental - The Periodic Table of Elements - Elements Listed by Atomic  

NLE Websites -- All DOE Office Websites (Extended Search)

Atomic Number Atomic Number 1 Hydrogen H 2 Helium He 3 Lithium Li 4 Beryllium Be 5 Boron B 6 Carbon C 7 Nitrogen N 8 Oxygen O 9 Fluorine F 10 Neon Ne 11 Sodium Na 12 Magnesium Mg 13 Aluminum Al 14 Silicon Si 15 Phosphorus P 16 Sulfur S 17 Chlorine Cl 18 Argon Ar 19 Potassium K 20 Calcium Ca 21 Scandium Sc 22 Titanium Ti 23 Vanadium V 24 Chromium Cr 25 Manganese Mn 26 Iron Fe 27 Cobalt Co 28 Nickel Ni 29 Copper Cu 30 Zinc Zn 31 Gallium Ga 32 Germanium Ge 33 Arsenic As 34 Selenium Se 35 Bromine Br 36 Krypton Kr 37 Rubidium Rb 38 Strontium Sr 39 Yttrium Y 40 Zirconium Zr 41 Niobium Nb 42 Molybdenum Mo 43 Technetium Tc 44 Ruthenium Ru 45 Rhodium Rh 46 Palladium Pd 47 Silver Ag 48 Cadmium Cd 49 Indium In 50 Tin Sn 51 Antimony Sb 52 Tellurium Te 53 Iodine I 54 Xenon Xe 55 Cesium Cs 56 Barium Ba 57 Lanthanum La 58 Cerium Ce

127

Group Publications-Surface Electrochemistry and Electrocatalysis (SEE)  

NLE Websites -- All DOE Office Websites (Extended Search)

SEE Group Publications 2009 - present SEE Group Publications 2009 - present 2013 Ordered Bilayer Ruthenium-Platinum Core-Shell Nanoparticles as Carbon Monoxide-Tolerant Fuel Cell Catalysts, Y.-C. Hsieh, Y. Zhang, D. Su, V. Volkov, R. Si, L. Wu, Y. Zhu, W. An, P. Liu, P. He, S. Ye, R. R. Adzic, and J.X. Wang, Nature Communications, in press. Pt Monolayer on Au-Stabilized PdNi Core-Shell Nanoparticles for Oxygen Reduction Reaction, K.A. Kuttiyiel, K. Sasaki, D. Su, M.B. Vukmirovic, N.S. Marinkovic, R.R. Adzic, Electrochimica Acta, in press. Oxygen Reduction Activity of IrCu Core Platinum Monolayer Shell Nano-electrocatalysts, Y.M. Choi, K.A. Kuttiyiel, J. P. Labis, K. Sasaki, G.-G. Park, T.-H. Yang, R.R. Adzic, Topics in Catalysis, in press. The Role of Rhodium and Tin Oxide in the Platinum-based Electrocatalysts for Ethanol Oxidation to CO2, M. Li, W.-P. Zhou, N.S. Marinkovic, K. Sasaki, R.R. Adzic, Electrochimica Acta, 104 (2013) 454-461.

128

Method for bonding thin film thermocouples to ceramics  

DOE Patents (OSTI)

A method is provided for adhering a thin film metal thermocouple to a ceramic substrate used in an environment up to 700 degrees Centigrade, such as at a cylinder of an internal combustion engine. The method includes the steps of: depositing a thin layer of a reactive metal on a clean ceramic substrate; and depositing thin layers of platinum and a platinum-10% rhodium alloy forming the respective legs of the thermocouple on the reactive metal layer. The reactive metal layer serves as a bond coat between the thin noble metal thermocouple layers and the ceramic substrate. The thin layers of noble metal are in the range of 1-4 micrometers thick. Preferably, the ceramic substrate is selected from the group consisting of alumina and partially stabilized zirconia. Preferably, the thin layer of reactive metal is in the range of 0.015-0.030 micrometers (15-30 nanometers) thick. The preferred reactive metal is chromium. Other reactive metals may be titanium or zirconium. The thin layer of reactive metal may be deposited by sputtering in ultra high purity argon in a vacuum of approximately 2 milliTorr (0.3 Pascals).

Kreider, Kenneth G. (Potomac, MD)

1993-01-01T23:59:59.000Z

129

Active Hydrogenation Catalyst with a Structured, Peptide-Based Outer-Coordination Sphere  

Science Conference Proceedings (OSTI)

The synthesis, catalytic activity, and structural features of a rhodium-based hydrogenation catalyst containing a phosphine ligand coupled to a 14-residue peptide are reported. Both CD and NMR spectroscopy show that the peptide adopts a helical structure in 1:1:1 TFE/MeCN/H2O that is maintained when the peptide is attached to the ligand and when the ligand is attached to the metal complex. The metal complex hydrogenates aqueous solutions of 3-butenol to 1-butanol at 360 ± 50 turnovers/Rh/h at 294 K. This peptide- based catalyst represents a starting point for developing and characterizing a peptide-based outer-coordination sphere that can be used to introduce enzyme-like features into molecular catalysts. This work was funded by the US DOE Basic Energy Sciences, Chemical Sciences, Geoscience and Biosciences Division (AJ, JCL and WJS), the Office of Science Early Career Research Program through the Office of Basic Energy Sciences (GWB, MLR and WJS). Part of the research was conducted at the W.R. Wiley Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by U.S. Department of Energy’s Office of Biolog-ical and Environmental Research (BER) program located at Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle for the U.S. Department of Energy.

Jain, Avijita; Buchko, Garry W.; Reback, Matthew L.; O'Hagan, Molly J.; Ginovska-Pangovska, Bojana; Linehan, John C.; Shaw, Wendy J.

2012-10-05T23:59:59.000Z

130

Process for functionalizing alkanes  

DOE Green Energy (OSTI)

Process for functionalizing saturated hydrocarbons comprising: (a) reacting said saturated hydrocarbons of the formula: R.sub.1 H wherein H represents a hydrogen atom; and R.sub.1 represents a saturated hydrocarbon radical, with a metal complex of the formula: CpRh[P(R.sub.2).sub.3 ]H.sub.2 wherein Cp represents a cyclopentadienyl or alkylcyclopentadienyl radical; Rh represents a rhodium atom; P represents a phosphorus atom; R.sub.2 represents a hydrocarbon radical; H represents a hydrogen atom, in the presence of ultraviolet radiation to form a hydridoalkyl complex of the formula: CpRh[P(R.sub.2).sub.3 ](R.sub.1)H (b) reacting said hydridoalkyl complex with an organic halogenating agent such as a tetrahalomethane or a haloform of the formulas: CX'X''X'''X'''' or CHX'X''X''' wherein X', X'', X'", X"" represent halogens selected from bromine, iodine or chlorine atom, at a temperature in the range of about -60.degree. to -17.degree. C. to form the corresponding haloalkyl complex of step (a) having the formula: CpRhPMe.sub.3 RX; and, (c) reacting said haloalkyl complex formed in (b) with halogen (X.sub.2) at a temperature in the range of about -60.degree. to 25.degree. C. (i.e., ambient) to form a functional haloalkyl compound.

Bergman, Robert G. (Kensington, CA); Janowicz, Andrew H. (Wilmington, DE); Periana, Roy A. (Berkeley, CA)

1988-01-01T23:59:59.000Z

131

Process for removal of mineral particulates from coal-derived liquids  

SciTech Connect

Suspended mineral solids are separated from a coal-derived liquid containing the solids by a process comprising the steps of: (a) contacting said coal-derived liquid containing solids with a molten additive having a melting point of 100.degree.-500.degree. C. in an amount of up to 50 wt. % with respect to said coal-derived liquid containing solids, said solids present in an amount effective to increase the particle size of said mineral solids and comprising material or mixtures of material selected from the group of alkali metal hydroxides and inorganic salts having antimony, tin, lithium, sodium, potassium, magnesium, calcium, beryllium, aluminum, zinc, molybdenum, cobalt, nickel, ruthenium, rhodium or iron cations and chloride, iodide, bromide, sulfate, phosphate, borate, carbonate, sulfite, or silicate anions; and (b) maintaining said coal-derived liquid in contact with said molten additive for sufficient time to permit said mineral matter to agglomerate, thereby increasing the mean particle size of said mineral solids; and (c) recovering a coal-derived liquid product having reduced mineral solids content. The process can be carried out with less than 5 wt. % additive and in the absence of hydrogen pressure.

McDowell, William J. (Knoxville, TN)

1980-01-01T23:59:59.000Z

132

Process for functionalizing alkanes  

DOE Patents (OSTI)

Process for functionalizing saturated hydrocarbons comprising: (a) reacting said saturated hydrocarbons of the formula: R.sub.1 H wherein H represents a hydrogen atom; and R.sub.1 represents a saturated hydrocarbon radical, with a metal complex of the formula: CpRh[P(R.sub.2).sub.3 ]H.sub.2 wherein Cp represents a cyclopentadienyl or alkylcyclopentadienyl radical; Rh represents a rhodium atom; P represents a phosphorus atom; R.sub.2 represents a hydrocarbon radical; H represents a hydrogen atom, in the presence of ultraviolet radiation to form a hydridoalkyl complex of the formula: CpRh[P(R.sub.2).sub.3 ](R.sub.1)H (b) reacting said hydridoalkyl complex with an organic halogenating agent such as a tetrahalomethane or a haloform of the formulas: CX'X''X'''X'''' or CHX'X''X''' wherein X', X'', X'", X"" represent halogens selected from bromine, iodine or chlorine atom, at a temperature in the range of about -60.degree. to -17.degree. C. to form the corresponding haloalkyl complex of step (a) having the formula: CpRhPMe.sub.3 RX; and, (c) reacting said haloalkyl complex formed in (b) with halogen (X.sub.2) at a temperature in the range of about -60.degree. to 25.degree. C. (i.e., ambient) to form a functional haloalkyl compound.

Bergman, Robert G. (Kensington, CA); Janowicz, Andrew H. (Wilmington, DE); Periana, Roy A. (Berkeley, CA)

1988-01-01T23:59:59.000Z

133

On the Use of Thermal NF3 as the Fluorination and Oxidation Agent in Treatment of Used Nuclear Fuels  

SciTech Connect

This paper presents results of our investigation on the use of nitrogen trifluoride as the fluorination or fluorination/oxidation agent for use in a process for separating valuable constituents from used nuclear fuels by employing the volatility of many transition metal and actinide fluorides. Nitrogen trifluoride is less chemically and reactively hazardous than the hazardous and aggressive fluorinating agents used to prepare uranium hexafluoride and considered for fluoride volatility based nuclear fuels reprocessing. In addition, nitrogen trifluoride’s less aggressive character may be used to separate the volatile fluorides from used fuel and from themselves based on the fluorination reaction’s temperature sensitivity (thermal tunability) rather than relying on differences in sublimation/boiling temperature and sorbents. Our thermodynamic calculations found that nitrogen trifluoride has the potential to produce volatile fission product and actinide fluorides from candidate oxides and metals. Our simultaneous thermogravimetric and differential thermal analyses found that the oxides of lanthanum, cerium, rhodium, and plutonium fluorinated but did not form volatile fluorides and that depending on temperature volatile fluorides formed from the oxides of niobium, molybdenum, ruthenium, tellurium, uranium, and neptunium. We also demonstrated near-quantitative removal of uranium from plutonium in a mixed oxide.

Scheele, Randall D.; McNamara, Bruce K.; Casella, Andrew M.; Kozelisky, Anne E.

2012-05-01T23:59:59.000Z

134

Neutron spectroscopy. Progress report, July 1, 1972--June 30, 1973  

SciTech Connect

The main emphasis during the past year has been on analyzing and publishing results and the preparation for the impending startup of the newly modified Nevis cyclotron. Papers on the separated isotopes of Yb and W have been submitted to the Physical Review. The published results on Er confirm Dyson's theory of level spacing systematics. The total cross section, resonance parameters, and spin-parity values of Na below 300 keV have been submitted for publication. A report on the evaluation of the GAMMA /sub gamma /'s of /sup 238/U has been distributed. Extensive results on the Er isotopes, /sup 232/U / sup 152,154/Sm, /sup 151,153/Eu, Fe, La, In, Ta, F, Mg, Al, S, Cl, K and Ca have been obtained. A paper on the precision measurement of the 2200 m/s neutron- proton capture cross section has been submitted for publication. The background for fission measurements has been extensively analyzed, and modifications to the neutron source of the Nevis cyclotron will be made for the next run. New methods of analyzing-low-count-rate data have been developed to eliminate observation of spurious levels. The captive cross sections of thulium and rhodium have been analyzed; and the results, reported. (9 figures, 7 tables) (auth)

Havens, W.W. Jr.; Melkonian, E.; Felvinci, J.; Rahn, F.

1973-01-01T23:59:59.000Z

135

Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly progress report, January 1, 1980-March 31, 1980. [Pt/Rh, Pd, Pt, Rh, Ni/Rh, Rh/Re, Ni  

DOE Green Energy (OSTI)

Catalysts are being screened to steam reform hydrocarbons in an autothermal reformer (STR). Twenty-one samples have been screened in a 1-in.-diam (ATR) reactor using No. 2 oil as the hydrocarbon feed. A series of platinum-rhodium catalysts were evaluated to study the effect of varying compositions. A sample containing 1.7% Pt/0.3% Rh was most active but the difference among the samples was within the range of test variability. Development of a more realistic test has been started. The effect of O/sub 2//C level on the gas composition leaving the catalytic partial oxidation section has been determined. The amount of unreacted oil increases as O/sub 2//C level decreases. The unreacted oil is more aromatic than the feedstock. The gas composition contains considerably more olefins as the O/sub 2//C level decreases. Post-run catalyst characterization indicates that the catalyst carrier does not deteriorate in the ATR test. A drastic decrease in CO chemisorption is noted on the Pt/Rh samples. This decline in CO chemisorption could either be due to metal sintering or to carbon deposition on the metal. Other analysis are required to determine which is causing the decline in CO chemisorption. Very low coke levels were found on Pt, Rh, and Pt/Rh samples. Addition of Rh to nickel reduces the coke level over that observed for nickel catalysts.

Yarrington, R M; Feins, I R; Hwang, H S

1980-04-01T23:59:59.000Z

136

Catalyst for the production of hydrocarbons from the synthesis gas  

SciTech Connect

This patent describes a catalyst for the production of hydrocarbons from the synthesis gas, which comprises the combination of an iron-containing Fisher-Tropsch catalyst, a zeolite and at least one metal selected from the group consisting of ruthenium, rhodium, platinum, palladium, irridium, cobalt and molybdenum. The metal supported upon the iron-containing Fischer-Tropsch catalyst or supported upon a mixture of the iron-containing Fischer-Tropsch catalyst and the zeolite. The iron in terms of iron oxide in the iron-containing Fischer-Tropsch catalyst is present in an amount of 5 to 80% by weight, based on the combined weight of the iron oxide and zeolite. The metal is present in amounts of 0.3 to 5% by weight, based upon the combined weight of the iron oxide and the zeolite. The zeolite is selected from the group consisting of zeolites having a pore size of 5 o 9 A and a silica to alumina mole ratio of at least 12 is described.

Koikeda, M.; Suzuki, T.; Munemura, K.; Nishimoto, Y.; Imai, T.

1986-11-11T23:59:59.000Z

137

Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish  

DOE Green Energy (OSTI)

The concept of solar driven chemical reactions in a commercial-scale volumetric receiver/reactor on a parabolic concentrator was successfully demonstrated in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) test. Solar reforming of methane (CH{sub 4}) with carbon dioxide (CO{sub 2}) was achieved in a 64-cm diameter direct absorption reactor on a parabolic dish capable of 150 kW solar power. The reactor was a catalytic volumetric absorber consisting of a multi-layered, porous alumina foam disk coated with rhodium (Rh) catalyst. The system was operated during both steady-state and solar transient (cloud passage) conditions. The total solar power absorbed reached values up to 97 kW and the maximum methane conversion was 70%. Receiver thermal efficiencies ranged up to 85% and chemical efficiencies peaked at 54%. The absorber performed satisfactorily in promoting the reforming reaction during the tests without carbon formation. However, problems of cracking and degradation of the porous matrix, nonuniform dispersion of the Rh through the absorber, and catalyst deactivation due to sintering and possible encapsulation, must be resolved to achieve long-term operation and eventual commercialization. 17 refs., 11 figs., 1 tab.

Muir, J.F.; Hogan, R.E. Jr.; Skocypec, R.D. (Sandia National Labs., Albuquerque, NM (USA)); Buck, R. (Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Stuttgart (Germany, F.R.). Inst. fuer Technische Thermodynamik)

1990-01-01T23:59:59.000Z

138

Chemical Forms and Distribution of Platinum Group Metals and Technetium During Spent Fuel Reprocessing  

SciTech Connect

Amongst the fission products present in spent nuclear fuel of Nuclear Power Plants there are considerable quantities of platinum group metals (PGMs): ruthenium, rhodium and palladium. At the same time there are considerable amounts of technetium in the spent fuel, the problem of its removal at radiochemical plants being in operation encountering serious difficulties. Increased interest in this radionuclides is due not only to its rather large yield, but to higher mobility in the environment as well. However, the peculiarities of technetium chemistry in nitric acid solutions create certain problems when trying to separate it as a single product in the course of NPP's spent fuel reprocessing. The object of this work was to conduct a comprehensive analysis of platinum group metals and technetium behavior at various stages of spent fuel reprocessing and to seek the decisions which could make it possible to separate its as a single product. The paper will report data on platinum metals (PGM) and technetium distribution in spent fuel reprocessing products. The description of various techniques for palladium recovery from differing in composition radioactive solutions arising from reprocessing is given. (authors)

Pokhitonov, Y. [V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation)

2007-07-01T23:59:59.000Z

139

Quantitative Analysis  

Science Conference Proceedings (OSTI)

Table 1   Empirical atomic sensitivity factors relative to fluorine 1 s = 1 for some instruments (a)...� 0.72 Molybdenum 1.66 2.75 1.74 1.17 � 0.73 Technetium 1.89 3.15 1.92 1.24 � 0.73 Ruthenium 2.15 3.6 2.15 1.30 � 0.73 Rhodium 2.4 4.1 2.4 1.38 � 0.74 Palladium 2.7 4.6 2.7 1.43 � 0.74 Silver 3.1 5.2 3.1 1.52 � 0.75 Cadmium 3.5 � 3.5 1.60 � 0.75 Indium 3.9 � 3.9 1.68 � 0.75 Tin 4.3 � 4.3 1.77 � 0.75...

140

Dendrimer Templated Synthesis of One Nanometer Rh and Pt Particles Supported on Mesoporous Silica: Catalytic Activity for Ethylene and Pyrrole Hydrogenation.  

DOE Green Energy (OSTI)

Monodisperse rhodium (Rh) and platinum (Pt) nanoparticles as small as {approx}1 nm were synthesized within a fourth generation polyaminoamide (PAMAM) dendrimer, a hyperbranched polymer, in aqueous solution and immobilized by depositing onto a high-surface-area SBA-15 mesoporous support. X-ray photoelectron spectroscopy indicated that the as-synthesized Rh and Pt nanoparticles were mostly oxidized. Catalytic activity of the SBA-15 supported Rh and Pt nanoparticles was studied with ethylene hydrogenation at 273 and 293 K in 10 torr of ethylene and 100 torr of H{sub 2} after reduction (76 torr of H{sub 2} mixed with 690 torr of He) at different temperatures. Catalysts were active without removing the dendrimer capping but reached their highest activity after hydrogen reduction at a moderate temperature (423 K). When treated at a higher temperature (473, 573, and 673 K) in hydrogen, catalytic activity decreased. By using the same treatment that led to maximum ethylene hydrogenation activity, catalytic activity was also evaluated for pyrrole hydrogenation.

Huang, Wenyu; Kuhn, John N.; Tsung, Chia-Kuang; Zhang, Yawen; Habas, Susan E.; Yang, Peidong; Somorjai, Gabor A.

2008-05-09T23:59:59.000Z

Note: This page contains sample records for the topic "trevor houser rhodium" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish: I-test and analysis  

DOE Green Energy (OSTI)

The concept of solar driven chemical reaction in a commercial-scale volumetric receiver/reactor on a parabolic concentrator was successfully demonstrated in the CAtalytically Enhanced Solar Absorption Receiver (CAESAR) test. Solar reforming of methane (CH[sub 4]) with carbon dioxide (CO[sub 2]) was achieved in a 64 cm diameter direct absorption reactor on a parabolic dish capable of 150 kW solar power. The reactor was a catalytic volumetric absorber consisting of a multilayered, porous alumina foam disk coated with rhodium (Rh) catalyst. The system was operated during both steady-state and solar transient (cloud passage) conditions. The total solar power absorbed reached values up to 97 kW and the maximum methane conversion was 70%. Receiver thermal efficiencies ranged up to 85% and chemical efficiencies peaked at 54%. The absorber performed satisfactorily in promoting the reforming reaction during the tests without carbon formation. However, problems of cracking and degradation of the porous matrix, nonuniform dispersion of the Rh through the absorber, the catalyst deactivation due to sintering and possible encapsulation, must be resolved to achieve long-term operation and eventual commercialization.

Muir, J.F.; Hogan, R.E. Jr.; Skocypec, R.D. (Sandia National Lab., Albuquerque, NM (United States)); Buck, R. (DLR-ITT, Stuttgart (Germany))

1994-06-01T23:59:59.000Z

142

Hanford waste vitrification plant hydrogen generation study: Preliminary evaluation of alternatives to formic acid  

DOE Green Energy (OSTI)

Oxalic, glyoxylic, glycolic, malonic, pyruvic, lactic, levulinic, and citric acids as well as glycine have been evaluated as possible substitutes for formic acid in the preparation of feed for the Hanford waste vitrification plant using a non-radioactive feed stimulant UGA-12M1 containing substantial amounts of aluminum and iron oxides as well as nitrate and nitrite at 90C in the presence of hydrated rhodium trichloride. Unlike formic acid none of these carboxylic acids liberate hydrogen under these conditions and only malonic and citric acids form ammonia. Glyoxylic, glycolic, malonic, pyruvic, lactic, levulinic, and citric acids all appear to have significant reducing properties under the reaction conditions of interest as indicated by the observation of appreciable amounts of N{sub 2}O as a reduction product of,nitrite or, less likely, nitrate at 90C. Glyoxylic, pyruvic, and malonic acids all appear to be unstable towards decarboxylation at 90C in the presence of Al(OH){sub 3}. Among the carboxylic acids investigated in this study the {alpha}-hydroxycarboxylic acids glycolic and lactic acids appear to be the most interesting potential substitutes for formic acid in the feed preparation for the vitrification plant because of their failure to produce hydrogen or ammonia or to undergo decarboxylation under the reaction conditions although they exhibit some reducing properties in feed stimulant experiments.

King, R.B.; Bhattacharyya, N.K.; Kumar, V.

1996-02-01T23:59:59.000Z

143

Cryogenic explosion environment modeling and testing of space shuttle and light-weight radioisotope heater unit interactions  

SciTech Connect

In order to assess the risk to the world's populace in the event of a Space Shuttle accident when radioisotope-containing heat sources are on board, testing of that system must be performed to determine release point, environments required, and the size distribution of the released fuel. To evaluate the performance of the Light-Weight Radioisotope Heater Unit (LWRHU) (101 of these 1-W items are placed on the Galileo spacecraft which will be launched from the Space Shuttle), some high-velocity impact and flyer plate testing was carried out. The results showed that a bare urania-fueled LWRHU clad (approximately 1-mm thick platinum-30 wt % rhodium alloy) will withstand 1100 m/s flyer plate (3.5-mm thick aluminum) impacts and 330 m/s impacts upon the Space Shuttle floor (approximately 12-mm thick aluminum) without rupture or fuel release. Velocities in the order of 600 m/s on a steel surface will cause clad failure with fuel release. The fuel breakup patterns were characterized as to quantity in a specific size range. These data were employed in the formal Safety Analysis Report for the LWRHU to support the planned 1986 Galileo launch. 19 figs.

Johnson, E.W.

1985-10-01T23:59:59.000Z

144

US Department of Energy radioisotope customers with summary of radioisotope shipments, FY 1988  

Science Conference Proceedings (OSTI)

Pacific Northwest Laboratory (PNL) prepared this edition of the radioisotope customer list at the request of the Office of Health and Environmental Research (ER-73), Office of Energy Research, US Department of Energy (DOE). This is the 25th report in a series dating from 1964. This report covers DOE radioisotope sales and distribution activities by its facilities to domestic, foreign and other DOE facilities for FY 1988. The report is divided into five sections: radioisotope suppliers, facility contacts, and radioisotopes or services supplied; a list of customers, suppliers, and radioisotopes purchased; a list of radioisotopes purchased cross-referenced to customer numbers; geographic locations of radioisotope customers; and radioisotope sales and transfers -- FY 1988. Radioisotopes not previously reported in this series of reports were argon-37, arsenic-72, arsenic-73, bismuth-207, gadolinium-151, rhenium-188, rhodium-101, selenium-72, xenon-123 and zirconium-88. The total value of DOE radioisotope sales for FY 1988 was $11.1 million, an increase of 3% from FY 1987.

Van Houten, N.C.

1989-06-01T23:59:59.000Z

145

Method of generating hydrogen by catalytic decomposition of water  

DOE Green Energy (OSTI)

A method for producing hydrogen includes providing a feed stream comprising water; contacting at least one proton conducting membrane adapted to interact with the feed stream; splitting the water into hydrogen and oxygen at a predetermined temperature; and separating the hydrogen from the oxygen. Preferably the proton conducting membrane comprises a proton conductor and a second phase material. Preferable proton conductors suitable for use in a proton conducting membrane include a lanthanide element, a Group VIA element and a Group IA or Group IIA element such as barium, strontium, or combinations of these elements. More preferred proton conductors include yttrium. Preferable second phase materials include platinum, palladium, nickel, cobalt, chromium, manganese, vanadium, silver, gold, copper, rhodium, ruthenium, niobium, zirconium, tantalum, and combinations of these. More preferably second phase materials suitable for use in a proton conducting membrane include nickel, palladium, and combinations of these. The method for generating hydrogen is preferably preformed in the range between about 600.degree. C. and 1,700.degree. C.

Balachandran, Uthamalingam (Hinsdale, IL); Dorris, Stephen E. (LaGrange Park, IL); Bose, Arun C. (Pittsburgh, PA); Stiegel, Gary J. (Library, PA); Lee, Tae-Hyun (Naperville, IL)

2002-01-01T23:59:59.000Z

146

Process for preparing schottky diode contacts with predetermined barrier heights  

DOE Patents (OSTI)

A process is provided for producing a Schottky diode having a preselected barrier height .phi..sub.Bn. The substrate is preferably n-GaAs, the metallic contact is derived from a starting alloy of the Formula [.SIGMA.M.sub..delta. ](Al.sub.x Ga.sub.1-x) wherein: .SIGMA.M is a moiety which consists of at least one M, and when more than one M is present, each M is different, M is a Group VIII metal selected from the group consisting of nickel, cobalt, ruthenium, rhodium, indium and platinum, .delta. is a stoichiometric coefficient whose total value in any given .SIGMA.M moiety is 1, and x is a positive number between 0 and 1 (that is, x ranges from greater than 0 to less than 1). Also, the starting alloy is capable of forming with the substrate a two phase equilibrium reciprocal system of the binary alloy mixture [.SIGMA.M.sub..delta. ]Ga-[.SIGMA.M.sub..delta. ]Al-AlAs-GaAs. When members of an alloy subclass within this Formula are each preliminarily correlated with the barrier height .phi..sub.Bn of a contact producable therewith, then Schottky diodes of predetermined barrier heights are producable by sputtering and annealing. Further provided are the product Schottky diodes that are produced according to this process.

Chang, Y. Austin (Middleton, WI); Jan, Chia-Hong (Portland, OR); Chen, Chia-Ping (Madison, WI)

1996-01-01T23:59:59.000Z

147

Separation of gas mixtures by supported complexes. Final report, 1 October 1982-30 September 1984  

DOE Green Energy (OSTI)

This final report covers research performed to identify and demonstrate advantageous procedures for the chemical separation of gases, such as CO, CO/sub 2/, and H/sub 2/, from medium-Btu gas mixtures by use of supported complexes. Three complexes were chosen for rapid gas uptake and selectivity at 25/sup 0/C from among a group of 22 coordination complexes synthesized during this program. The three complexes showed considerable selectivity toward individual gases. For instance, Pd/sub 2/(dpm)/sub 2/Cl/sub 2/ or bis-..mu..-(bisdiphenylphosphinomethane)-dichlorodipalladium (Pd-Pd), rapidly bound carbon monoxide from solution. This complex could be regenerated, with the carbon monoxide reversibly removed, by warming to 40/sup 0/C. The presence of other gases, such as carbon dioxide, oxygen, nitrogen, hydrogen, ethylene, or acetylene, had no effect upon the rapid uptake of carbon monoxide or its removal. Such selectivity was also noted with Ru(CO)/sub 2/(PPh/sub 3/)/sub 3/, biscarbonyltris(triphenylphosphine)ruthenium. Although this complex bound hydrogen, carbon monoxide, and oxygen in solution, the hydrogen was taken up twice as fast as carbon monoxide and seven times faster than oxygen. These gases could be removed from the complex with mild heat or decreased pressure. Crystalline Rh(OH)(CO)(PPh/sub 3/)/sub 2/, hydroxocarbonylbis(triphenylphosphine)rhodium, rapidly bound carbon dioxide; the complex was regenerated at 50/sup 0/C under reduced pressure. The rapid uptake of carbon dioxide by this complex was not changed in the presence of oxygen. In general the three selected crystalline or solvent dissolved complexes performed well in the absence of polymeric support. The stability and favorable kinetics of the three complexes suggest that they could be utilized in a solution system for gas separation (Conceptual Analyses and Preliminary Economics). Further, these complexes appear to be superb candidates as transport agents for facilitated-transport, membrane systems. 69 references, 21 figures.

Nelson, D.A.; Hallen, R.T.; Lilga, M.A.

1985-01-01T23:59:59.000Z

148

Evaluation of alternative chemical additives for high-level waste vitrification feed preparation processing  

SciTech Connect

During the development of the feed processing flowsheet for the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS), research had shown that use of formic acid (HCOOH) could accomplish several processing objectives with one chemical addition. These objectives included the decomposition of tetraphenylborate, chemical reduction of mercury, production of acceptable rheological properties in the feed slurry, and controlling the oxidation state of the glass melt pool. However, the DEPF research had not shown that some vitrification slurry feeds had a tendency to evolve hydrogen (H{sub 2}) and ammonia (NH{sub 3}) as the result of catalytic decomposition of CHOOH with noble metals (rhodium, ruthenium, palladium) in the feed. Testing conducted at Pacific Northwest Laboratory and later at the Savannah River Technical Center showed that the H{sub 2} and NH{sub 3} could evolve at appreciable rates and quantities. The explosive nature of H{sub 2} and NH{sub 3} (as ammonium nitrate) warranted significant mitigation control and redesign of both facilities. At the time the explosive gas evolution was discovered, the DWPF was already under construction and an immediate hardware fix in tandem with flowsheet changes was necessary. However, the Hanford Waste Vitrification Plant (HWVP) was in the design phase and could afford to take time to investigate flowsheet manipulations that could solve the problem, rather than a hardware fix. Thus, the HWVP began to investigate alternatives to using HCOOH in the vitrification process. This document describes the selection, evaluation criteria, and strategy used to evaluate the performance of the alternative chemical additives to CHOOH. The status of the evaluation is also discussed.

Seymour, R.G.

1995-06-07T23:59:59.000Z

149

Task 4.9 -- Value-added products from syngas. Semi-annual report, July 1--December 31, 1996  

DOE Green Energy (OSTI)

The work on advanced fuel forms in 1996 focused on the synthesis of higher alcohols from mixtures of hydrogen and carbon dioxide (syngas) from coal gasification. Initial work in this project utilized a novel molybdenum sulfide catalyst previously shown to be active for hydrodesulfurization reactions of coal liquids. A pressurized fixed-bed flow-through reactor was constructed, and the MoS{sub 2} catalysts were tested with syngas under a variety of conditions. Unfortunately, the catalysts, even with higher molybdenum loading and addition of promoters, failed to give alcohol products. A batch reactor test of the catalyst was also conducted, but did not produce alcohol products. Group VIII metals have been used previously in catalysts for syngas reactions. Ruthenium and rhodium catalysts were prepared by impregnation of a hydrotalcite support. Tests with these catalysts in flow-through reactors also did not produce the desired alcohol products. The formation of higher alcohols from smaller ones, such as methanol and ethanol, could be commercially important if high selectivity could be achieved. The methanol and ethanol would be derived from syngas and fermentation, respectively. Based on previous work in other laboratories, it was hypothesized that the hydrotalcite-supported MoS{sub 2} or Ru or Rh catalysts could catalyze the formation of butyl alcohols. Although the desired 1-butanol was obtained in batch reactions with the promoted ruthenium catalyst, the reaction was not as selective as desired. Product suitable for a lower-vapor-pressure gasoline oxygenate additive was obtained, but it may not be economical to market such products in competition with methyl tertiary-butyl ether (MTBE). Flow-through catalytic bed reactions were not successful.

Olson, E.S.; Sharma, R.K.

1997-08-01T23:59:59.000Z

150

Transmission of broad W/Rh and W/Al (target/filter) x-ray beams operated at 25-49 kVp through common shielding materials  

SciTech Connect

Purpose: To provide transmission data for broad 25-39 kVp (kilovolt peak) W/Rh and 25-49 kVp W/Al (target/filter, W-tungsten, Rh-rhodium, and Al-aluminum) x-ray beams through common shielding materials, such as lead, concrete, gypsum wallboard, wood, steel, and plate glass. Methods: The unfiltered W-target x-ray spectra measured on a Selenia Dimensions system (Hologic Inc., Bedford, MA) set at 20-49 kVp were, respectively, filtered using 50-{mu}m Rh and 700-{mu}m Al, and were subsequently used for Monte Carlo calculations. The transmission of broad x-ray beams through shielding materials was simulated using Geant4 low energy electromagnetic physics package with photon- and electron-processes above 250 eV, including photoelectric effect, Compton scattering, and Rayleigh scattering. The calculated transmission data were fitted using Archer equation with a robust fitting algorithm. Results: The transmission of broad x-ray beams through the above-mentioned shielding materials was calculated down to about 10{sup -5} for 25-39 kVp W/Rh and 25-49 kVp W/Al. The fitted results of {alpha}, {beta}, and {gamma} in Archer equation were provided. The {alpha} values of kVp Greater-Than-Or-Slanted-Equal-To 40 were approximately consistent with those of NCRP Report No. 147. Conclusions: These data provide inputs for the shielding designs of x-ray imaging facilities with W-anode x-ray beams, such as from Selenia Dimensions.

Li Xinhua; Zhang Da; Liu, Bob [Division of Diagnostic Imaging Physics, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States)

2012-07-15T23:59:59.000Z

151

Final Report: Investigation of Catalytic Pathways for Lignin Breakdown into Monomers and Fuels  

DOE Green Energy (OSTI)

Lignin is a biopolymer that comprises up to 35% of woody biomass by dry weight. It is currently underutilized compared to cellulose and hemicellulose, the other two primary components of woody biomass. Lignin has an irregular structure of methoxylated aromatic groups linked by a suite of ether and alkyl bonds which makes it difficult to degrade selectively. However, the aromatic components of lignin also make it promising as a base material for the production of aromatic fuel additives and cyclic chemical feed stocks such as styrene, benzene, and cyclohexanol. Our laboratory research focused on three methods to selectively cleave and deoxygenate purified lignin under mild conditions: acidolysis, hydrogenation and electrocatalysis. (1) Acidolysis was undertaken in CH2Cl2 at room temperature. (2) Hydrogenation was carried out by dissolving lignin and a rhodium catalyst in 1:1 water:methoxyethanol under a 1 atm H2 environment. (3) Electrocatalysis of lignin involved reacting electrically generated hydrogen atoms at a catalytic palladium cathode with lignin dissolved in a solution of aqueous methanol. In all of the experiments, the lignin degradation products were identified and quantified by gas chromatography mass spectroscopy and flame ionization detection. Yields were low, but this may have reflected the difficulty in recovering the various fractions after conversion. The homogeneous hydrogenation of lignin showed fragmentation into monomers, while the electrocatalytic hydrogenation showed production of polyaromatic hydrocarbons and substituted benzenes. In addition to the experiments, promising pathways for the conversion of lignin were assessed. Three conversion methods were compared based on their material and energy inputs and proposed improvements using better catalyst and process technology. A variety of areas were noted as needing further experimental and theoretical effort to increase the feasibility of lignin conversion to fuels.

Gluckstein, Jeffrey A [ORNL; Hu, Michael Z. [ORNL; Kidder, Michelle [ORNL; McFarlane, Joanna [ORNL; Narula, Chaitanya Kumar [ORNL; Sturgeon, Matthew R [ORNL

2010-12-01T23:59:59.000Z

152

Analytical Results of DWPF Glass Sample Taken During Pouring of Canister S01913  

SciTech Connect

The Defense Waste Processing Facility (DWPF) began processing Sludge Batch 2 (SB2) (Macrobatch 3) in December 2001 as part of Sludge Receipt and Adjustment Tank (SRAT) Batch 208. Macrobatch 3 consists of the contents of Tank 40 and Tank 8 in approximately equal proportions. A glass sample was obtained while pouring Canister S01913 and was sent to the Savannah River National Laboratory (SRNL) Shielded Cells for characterization. This report contains observations of the glass sample, results for the density, the chemical composition, the Product Consistency Test (PCT) and the radionuclide results needed for the Production Record for Canister S01913. The following conclusions are drawn from this work: (1) The glass sample taken during the filling of canister S01913 received at SRNL weighed 33.04 grams and was dark and reflective with no obvious inclusions indicating the glass was homogeneous. (2) The results of the composition for glass sample S01913 are in good agreement ({+-} 15%) with the DWPF SME results for Batch Number 254, the SME Batch that was being fed to the melter when the sample was collected. (3) The calculated WDF was 2.58. (4) Acid dissolution of the glass samples may not have completely dissolved the noble metals rhodium and ruthenium. (5) The PCT results for the glass (normalized boron release of 1.18 g/L) indicate that it is greater than seven standard deviations more durable than the EA glass; thus, the glass meets the waste acceptance criterion for durability. (6) The measured density of the glass was 2.56 {+-} 0.03 g/cm{sup 3}.

Bannochie, C

2005-10-01T23:59:59.000Z

153

Fate of Noble Metals during the Pyroprocessing of Spent Nuclear Fuel  

SciTech Connect

During the pyroprocessing of spent nuclear fuel by electrochemical techniques, fission products are separated as the fuel is oxidized at the anode and refined uranium is deposited at the cathode. Those fission products that are oxidized into the molten salt electrolyte are considered active metals while those that do not react are considered noble metals. The primary noble metals encountered during pyroprocessing are molybdenum, zirconium, ruthenium, rhodium, palladium, and technetium. Pyroprocessing of spent fuel to date has involved two distinctly different electrorefiner designs, in particular the anode to cathode configuration. For one electrorefiner, the anode and cathode collector are horizontally displaced such that uranium is transported across the electrolyte medium. As expected, the noble metal removal from the uranium during refining is very high, typically in excess of 99%. For the other electrorefiner, the anode and cathode collector are vertically collocated to maximize uranium throughput. This arrangement results in significantly less noble metals removal from the uranium during refining, typically no better than 20%. In addition to electrorefiner design, operating parameters can also influence the retention of noble metals, albeit at the cost of uranium recovery. Experiments performed to date have shown that as much as 100% of the noble metals can be retained by the cladding hulls while affecting the uranium recovery by only 6%. However, it is likely that commercial pyroprocessing of spent fuel will require the uranium recovery to be much closer to 100%. The above mentioned design and operational issues will likely be driven by the effects of noble metal contamination on fuel fabrication and performance. These effects will be presented in terms of thermal properties (expansion, conductivity, and fusion) and radioactivity considerations. Ultimately, the incorporation of minor amounts of noble metals from pyroprocessing into fast reactor metallic fuel will be shown to be of no consequence to reactor performance.

B.R. Westphal; D. Vaden; S.X. Li; G.L. Fredrickson; R.D. Mariani

2009-09-01T23:59:59.000Z

154

Evaluation of Alternate Materials for Coated Particle Fuels for the Gas-Cooled Fast Reactor. Laboratory Directed Research and Development Program FY 2006 Final Report  

Science Conference Proceedings (OSTI)

Candidate ceramic materials were studied to determine their suitability as Gas-Cooled Fast Reactor particle fuel coatings. The ceramics examined in this work were: TiC, TiN, ZrC, ZrN, AlN, and SiC. The studies focused on (i) chemical reactivity of the ceramics with fission products palladium and rhodium, (ii) the thermomechanical stresses that develop in the fuel coatings from a variety of causes during burnup, and (iii) the radiation resiliency of the materials. The chemical reactivity of TiC, TiN, ZrC, and ZrN with Pd and Rh were all found to be much lower than that of SiC. A number of important chemical behaviors were observed at the ceramic-metal interfaces, including the formation of specific intermetallic phases and a variation in reaction rates for the different ceramics investigated. Based on the data collected in this work, the nitride ceramics (TiN and ZrN) exhibit chemical behavior that is characterized by lower reaction rates with Pd and Rh than the carbides TiC and ZrC. The thermomechanical stresses in spherical fuel particle ceramic coatings were modeled using finite element analysis, and included contributions from differential thermal expansion, fission gas pressure, fuel kernel swelling, and thermal creep. In general the tangential stresses in the coatings during full reactor operation are tensile, with ZrC showing the lowest values among TiC, ZrC, and SiC (TiN and ZrN were excluded from the comprehensive calculations due to a lack of available materials data). The work has highlighted the fact that thermal creep plays a critical role in the development of the stress state of the coatings by relaxing many of the stresses at high temperatures. To perform ion irradiations of sample materials, an irradiation beamline and high-temperature sample irradiation stage was constructed at the University of Wisconsin’s 1.7MV Tandem Accelerator Facility. This facility is now capable of irradiating of materials to high dose while controlling sample temperature up to 800ºC.

Paul A. Demkowicz; Karen Wright; Jian Gan; David Petti; Todd Allen; Jake Blanchard

2006-09-01T23:59:59.000Z

155

IMPACT OF NOBLE METALS AND MERCURY ON HYDROGEN GENERATION DURING HIGH LEVEL WASTE PRETREATMENT AT THE SAVANNAH RIVER SITE  

DOE Green Energy (OSTI)

The Defense Waste Processing Facility (DWPF) at the Savannah River Site vitrifies radioactive High Level Waste (HLW) for repository internment. The process consists of three major steps: waste pretreatment, vitrification, and canister decontamination/sealing. HLW consists of insoluble metal hydroxides (primarily iron, aluminum, calcium, magnesium, manganese, and uranium) and soluble sodium salts (carbonate, hydroxide, nitrite, nitrate, and sulfate). The pretreatment process in the Chemical Processing Cell (CPC) consists of two process tanks, the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) as well as a melter feed tank. During SRAT processing, nitric and formic acids are added to the sludge to lower pH, destroy nitrite and carbonate ions, and reduce mercury and manganese. During the SME cycle, glass formers are added, and the batch is concentrated to the final solids target prior to vitrification. During these processes, hydrogen can be produced by catalytic decomposition of excess formic acid. The waste contains silver, palladium, rhodium, ruthenium, and mercury, but silver and palladium have been shown to be insignificant factors in catalytic hydrogen generation during the DWPF process. A full factorial experimental design was developed to ensure that the existence of statistically significant two-way interactions could be determined without confounding of the main effects with the two-way interaction effects. Rh ranged from 0.0026-0.013% and Ru ranged from 0.010-0.050% in the dried sludge solids, while initial Hg ranged from 0.5-2.5 wt%, as shown in Table 1. The nominal matrix design consisted of twelve SRAT cycles. Testing included: a three factor (Rh, Ru, and Hg) study at two levels per factor (eight runs), three duplicate midpoint runs, and one additional replicate run to assess reproducibility away from the midpoint. Midpoint testing was used to identify potential quadratic effects from the three factors. A single sludge simulant was used for all tests and was spiked with the required amount of noble metals immediately prior to performing the test. Acid addition was kept effectively constant except to compensate for variations in the starting mercury concentration. SME cycles were also performed during six of the tests.

Stone, M; Tommy Edwards, T; David Koopman, D

2009-03-03T23:59:59.000Z

156

Model catalytic studies of single crystal, polycrystalline metal, and supported catalysts  

E-Print Network (OSTI)

This dissertation is focused on understanding the structure-activity relationship in heterogeneous catalysis by studying model catalytic systems. The catalytic oxidation of CO was chosen as a model reaction for studies on a variety of catalysts. A series of Au/TiO2 catalysts were prepared from various metalorganic gold complexes. The catalytic activity and the particle size of the gold catalysts were strongly dependent on the gold complexes. The Au/TiO2 catalyst prepared from a tetranuclear gold complex showed the best performance for CO oxidation, and the average gold particle size of this catalyst was 3.1 nm. CO oxidation was also studied over Au/MgO catalysts, where the MgO supports were annealed to various temperatures between 900 and 1300 K prior to deposition of Au. A correlation was found between the activity of Au clusters for the catalytic oxidation of CO and the F-center concentration in the MgO support. In addition, the catalytic oxidation of CO was studied in a batch reactor over supported Pd/Al2O3 catalysts, a Pd(100) single crystal, as well as polycrystalline metals of rhodium, palladium, and platinum. A hyperactive state, corresponding to an oxygen covered surface, was observed at high O2/CO ratios at elevated pressures. The reaction rate at this state was significantly higher than that on CO-covered surfaces at stoichiometric conditions. The oxygen chemical potential required to achieve the hyperactive state depends on the intrinsic properties of the metal, the particle size, and the reaction temperature. A well-ordered ultra-thin titanium oxide film was synthesized on the Mo(112) surface as a model catalyst support. Two methods were used to prepare this Mo(112)- (8x2)-TiOx film, including direct growth on Mo(112) and indirect growth by deposition of Ti onto monolayer SiO2/Mo(112). The latter method was more reproducible with respect to film quality as determined by low-energy electron diffraction and scanning tunneling microscopy. The thickness of this TiOx film was one monolayer and the oxidation state of Ti was +3 as determined by Auger spectroscopy, high-resolution electron energy loss spectroscopy, and X-ray photoelectron spectroscopy.

Yan, Zhen

2007-12-01T23:59:59.000Z

157

TEMPERATURE MONITORING OPTIONS AVAILABLE AT THE IDAHO NATIONAL LABORATORY ADVANCED TEST REACTOR  

SciTech Connect

As part of the Advanced Test Reactor National Scientific User Facility (ATR NSUF) program, the Idaho National Laboratory (INL) has developed in-house capabilities to fabricate, test, and qualify new and enhanced sensors for irradiation testing. To meet recent customer requests, an array of temperature monitoring options is now available to ATR users. The method selected is determined by test requirements and budget. Melt wires are the simplest and least expensive option for monitoring temperature. INL has recently verified the melting temperature of a collection of materials with melt temperatures ranging from 100 to 1000 C with a differential scanning calorimeter installed at INL’s High Temperature Test Laboratory (HTTL). INL encapsulates these melt wires in quartz or metal tubes. In the case of quartz tubes, multiple wires can be encapsulated in a single 1.6 mm diameter tube. The second option available to ATR users is a silicon carbide temperature monitor. The benefit of this option is that a single small monitor (typically 1 mm x 1 mm x 10 mm or 1 mm diameter x 10 mm length) can be used to detect peak irradiation temperatures ranging from 200 to 800 C. Equipment has been installed at INL’s HTTL to complete post-irradiation resistivity measurements on SiC monitors, a technique that has been found to yield the most accurate temperatures from these monitors. For instrumented tests, thermocouples may be used. In addition to Type-K and Type-N thermocouples, a High Temperature Irradiation Resistant ThermoCouple (HTIR-TC) was developed at the HTTL that contains commercially-available doped molybdenum paired with a niobium alloy thermoelements. Long duration high temperature tests, in furnaces and in the ATR and other MTRs, demonstrate that the HTIR-TC is accurate up to 1800 C and insensitive to thermal neutron interactions. Thus, degradation observed at temperatures above 1100 C with Type K and N thermocouples and decalibration due to transmutation with tungsten-rhenium and platinum rhodium thermocouples can be avoided. INL is also developing an Ultrasonic Thermometry (UT) capability. In addition to small size, UT’s offer several potential advantages over other temperature sensors. Measurements may be made near the melting point of the sensor material, potentially allowing monitoring of temperatures up to 3000 C. In addition, because no electrical insulation is required, shunting effects are avoided. Most attractive, however, is the ability to introduce acoustic discontinuities to the sensor, as this enables temperature measurements at several points along the sensor length. As discussed in this paper, the suite of temperature monitors offered by INL is not only available to ATR users, but also to users at other MTRs.

J.E. Daw; J.L. Rempe; D.L. Knudson; T. Unruh; B.M. Chase; K.L Davis

2012-03-01T23:59:59.000Z

158

Process for alkane group dehydrogenation with organometallic catalyst  

DOE Patents (OSTI)

An improved process is described for the catalytic dehydrogenation of organic molecules having a ##STR1## group to produce a ##STR2## group. The organic molecules are: ##STR3## wherein: A.sup.1, A.sup.2, A.sup.3, and A.sup.4 are each independently P, As or N: E.sup.2 is independently C or N; E.sup.3 is independently C, Si or Ge; E.sup.4 is independently C, Si, or Ge; and E.sup.5 is independently C, Si or Ge; M.sup.1, M.sup.2, M.sup.3, and M.sup.4 each is a metal atom independently selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium and platinum; Q.sup.1, Q.sup.2, Q.sup.3, and Q.sup.4 are each independently a direct bond, --CH.sub.2 --, --CH.sub.2 CH.sub.2 --, or CH.dbd.CH--; in structure I, structure II or structure IV, R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently selected from alkyl, alkenyl, cycloalkyl, and aryl, or R.sup.1 and R.sup.2 together and R.sup.3 and R.sup.4 together form a ring structure having from 4 to 10 carbon atoms, or in structure III, R.sup.5, R.sup.6, R.sup.7, and R.sup.8 are each independently selected from alkyl, alkenyl, cycloalkyl, and aryl, or R.sup.5 and R.sup.6 together and R.sup.7 and R.sup.8 together form a ring structure having from 4 to 10 carbon atoms, at a temperature of between about 100.degree. and 250.degree. C. for between about 1 hr and 300 days in the absence of N.sub.2. The surprisingly stable catalyst is a complex of an organic ligand comprising H, C, Si, N, P atoms, and a platinum group metal. The dehydrogenation is performed between about 100 to 200.degree. C., and has increased turnover.

Kaska, William C. (Goleta, CA); Jensen, Craig M. (Kailua, HI)

1998-01-01T23:59:59.000Z

159

Task 4.9 -- Value-added products from syngas  

DOE Green Energy (OSTI)

The work on advanced fuel forms in 1996 focused on the synthesis of higher alcohols from mixtures of hydrogen and carbon dioxide (syngas) from coal gasification. The conversion of coal gasification products to commercially valuable alcohols will provide an important new market for current and future gasification plants. Initial work in this project utilized a novel molybdenum sulfide catalyst previously shown to be active for hydrodesulfurization reactions of coal liquids. The support for the active metal sulfide is a layered mixed oxide (hydrotalcite) capable of interaction with the metal sites for catalysis of carbon monoxide reductions. These catalysts have a high surface area, are highly porous, and have basic and acidic functionality. A pressurized fixed-bed flow-through reactor was constructed, and the MoS{sub 2} catalysts were tested with syngas under a variety of conditions. Unfortunately, the catalysts, even with higher molybdenum loading and addition of promoters, failed to give alcohol products. A batch reactor test of the catalyst was also conducted, but did not produce alcohol products. Group 8 metals have been used previously in catalysts for syngas reactions. Ruthenium and rhodium catalysts were prepared by impregnation of a hydrotalcite support. Tests with these catalysts in flow-through reactors also did not produce the desired alcohol products. The formation of higher alcohols from smaller ones, such as methanol and ethanol, could be commercially important if high selectivity could be achieved. The methanol and ethanol would be derived from syngas and fermentation, respectively. Based on previous work in other laboratories, it was hypothesized that the hydrotalcite supported MoS{sub 2} or Ru or Rh catalysts could catalyze the formation of butyl alcohols. Although the desired 1-butanol was obtained in batch reactions with the promoted Ru catalyst, the reaction was not as selective as desired. Product suitable for a lower-vapor-pressure gasoline oxygenate additive was obtained, but it may not be economical to market such products in competition with methyl tertiary-butyl-ether. Flow-through catalytic bed reactions were not successful.

Olson, E.S.; Sharma, R.K.

1997-02-01T23:59:59.000Z

160

ANALYSIS OF DWPF SLUDGE BATCH 7A (MACROBATCH 8) POUR STREAM SAMPLES  

SciTech Connect

The Defense Waste Processing Facility (DWPF) began processing Sludge Batch 7a (SB7a), also referred to as Macrobatch 8 (MB8), in June 2011. SB7a is a blend of the heel of Tank 40 from Sludge Batch 6 (SB6) and the SB7a material that was transferred to Tank 40 from Tank 51. SB7a was processed using Frit 418. During processing of each sludge batch, the DWPF is required to take at least one glass sample to meet the objectives of the Glass Product Control Program (GPCP), which is governed by the DWPF Waste Compliance Plan, and to complete the necessary Production Records so that the final glass product may be disposed of at a Federal Repository. Three pour stream glass samples and two Melter Feed Tank (MFT) slurry samples were collected while processing SB7a. These additional samples were taken during SB7a to understand the impact of antifoam and the melter bubblers on glass redox chemistry. The samples were transferred to the Savannah River National Laboratory (SRNL) where they were analyzed. The following conclusions were drawn from the analytical results provided in this report: (1) The sum of oxides for the official SB7a pour stream glass is within the Product Composition Control System (PCCS) limits (95-105 wt%). (2) The average calculated Waste Dilution Factor (WDF) for SB7a is 2.3. In general, the measured radionuclide content of the official SB7a pour stream glass is in good agreement with the calculated values from the Tank 40 dried sludge results from the SB7a Waste Acceptance Program Specification (WAPS) sample. (3) As in previous pour stream samples, ruthenium and rhodium inclusions were detected by Scanning Electron Microscopy-Electron Dispersive Spectroscopy (SEM-EDS) in the official SB7a pour stream sample. (4) The Product Consistency Test (PCT) results indicate that the official SB7a pour stream glass meets the waste acceptance criteria for durability with a normalized boron release of 0.64 g/L, which is an order of magnitude less than the Environmental Assessment (EA) glass. (5) The measured density of the SB7a pour stream glass was 2.7 g/cm{sup 3}. (6) The Fe{sup 2+}/{Sigma}Fe ratios of the SB7a pour stream samples were in the range of 0.04-0.13, while the MFT sample glasses prepared by SRNL were in the range of 0.02-0.04.

Johnson, F.

2012-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "trevor houser rhodium" from the National Library of EnergyBeta (NLEBeta).
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161

Elimination Of Catalytic Hydrogen Generation In Defense Waste Processing Facility Slurries  

SciTech Connect

Based on lab-scale simulations of Defense Waste Processing Facility (DWPF) slurry chemistry, the addition of sodium nitrite and sodium hydroxide to waste slurries at concentrations sufficient to take the aqueous phase into the alkaline region (pH > 7) with approximately 500 mg nitrite ion/kg slurry (assuming <25 wt% total solids, or equivalently 2,000 mg nitrite/kg total solids) is sufficient to effectively deactivate the noble metal catalysts at temperatures between room temperature and boiling. This is a potential strategy for eliminating catalytic hydrogen generation from the list of concerns for sludge carried over into the DWPF Slurry Mix Evaporator Condensate Tank (SMECT) or Recycle Collection Tank (RCT). These conclusions are drawn in large part from the various phases of the DWPF catalytic hydrogen generation program conducted between 2005 and 2009. The findings could apply to various situations, including a solids carry-over from either the Sludge Receipt and Adjustment Tank (SRAT) or Slurry Mix Evaporator (SME) into the SMECT with subsequent transfer to the RCT, as well as a spill of formic acid into the sump system and transfer into an RCT that already contains sludge solids. There are other potential mitigating factors for the SMECT and RCT, since these vessels are typically operated at temperatures close to the minimum temperatures that catalytic hydrogen has been observed to occur in either the SRAT or SME (pure slurry case), and these vessels are also likely to be considerably more dilute in both noble metals and formate ion (the two essential components to catalytic hydrogen generation) than the two primary process vessels. Rhodium certainly, and ruthenium likely, are present as metal-ligand complexes that are favored under certain concentrations of the surrounding species. Therefore, in the SMECT or RCT, where a small volume of SRAT or SME material would be significantly diluted, conditions would be less optimal for forming or sustaining the catalytic ligand species. Such conditions are likely to adversely impact the ability of the transferred mass to produce hydrogen at the same rate (per unit mass SRAT or SME slurry) as in the SRAT or SME vessels.

Koopman, D. C.

2013-01-22T23:59:59.000Z

162

Preparation and Heat-Treatment of DWPF Simulants With and Without Co-Precipitated Noble Metals  

DOE Green Energy (OSTI)

The Savannah River National Laboratory is in the process of investigating factors suspected of impacting catalytic hydrogen generation in the Chemical Process Cell of the Defense Waste Processing Facility, DWPF. Noble metal catalyzed hydrogen generation in simulation work constrains the allowable acid addition operating window in DWPF. This constraint potentially impacts washing strategies during sludge batch preparation. It can also influence decisions related to the addition of secondary waste streams to a sludge batch. Noble metals have historically been added as trim chemicals to process simulations. The present study investigated the potential conservatism that might be present from adding the catalytic species as trim chemicals to the final sludge simulant versus co-precipitating the noble metals into the insoluble sludge solids matrix. Parallel preparations of two sludge simulants targeting the composition of Sludge Batch 3 were performed in order to evaluate the impact of the form of noble metals. Identical steps were used except that one simulant had dissolved palladium, rhodium, and ruthenium present during the precipitation of the insoluble solids. Noble metals were trimmed into the other stimulant prior to process tests. Portions of both sludge simulants were held at 97 C for about eight hours to qualitatively simulate the effects of long term storage on particle morphology and speciation. The simulants were used as feeds for Sludge Receipt and Adjustment Tank, SRAT, process simulations. The following conclusions were drawn from the simulant preparation work: (1) The first preparation of a waste slurry simulant with co-precipitated noble metals was successful, based on the data obtained. It appears that 99+% of the noble metals were retained in the simulant. (2) Better control of carbonate, hydroxide, and post-wash trim chemical additions is needed before the new method of simulant preparation will be as reproducible as the old method. (3) The two new simulants were visually very viscous compared to the traditional SB3 simulant. (4) Heat-treatment reduced the viscosity of the two new simulants with and without coprecipitated noble metals, though they were still more viscous than the traditional SB3. (5) The approach of using a 97 C heat-treatment step to qualitatively simulate tank farm aging may not be optimal. A significant change in the base equivalent molarities of both simulants was observed during heat-treatment. (6) Heat-treatment appeared to make phosphates insoluble in water. The following recommendations came out of the work: (1) Washed slurry should be checked for TIC and base equivalents before calculating the final trim chemical additions of sodium carbonate and sodium hydroxide. (2) Final insoluble trim chemicals should be added to the slurry in the cross-flow filtration unit mixing tank, since significant slurry is lost in the CUF equipment. Adding the chemicals here would keep them in the correct proportion relative to the precipitated insoluble solids. (3) A composite wash and decant sample should be prepared containing proportionally weighted masses of each aqueous stream removed during preparation of a co-precipitated noble metal simulant. This sample should then be checked for noble metal losses. This would reduce the sample load, while still confirming that there was no significant noble metal loss. (4) A study of the impact of heat-treatment on existing simulants should be undertaken. If there is a shift in base equivalents, then SRNL acid stoichiometries may be biased relative to real waste. The study should be extended to several real wastes as well.

Koopman, David C.:Eibling, Russel E

2005-08-01T23:59:59.000Z

163

Reactivity studies of antitumor active dirhodium compounds with DNA oligonucleotides  

E-Print Network (OSTI)

The study of the mechanism of action of an antitumor active drug is essential for improving the efficacy and reducing the side effects of the drug as well as for developing better alternatives. In this vein, reactions of dirhodium compounds with DNA oligonucleotides were investigated by the techniques of mass spectrometry, HPLC, and NMR spectroscopic analytical methods. The relative reactivities of three dirhodium compounds, namely Rh2(O2CCH3)4, Rh2(O2CCF3)4, and [Rh2(O2CCH3)2(CH3CN)6](BF4)2, with DNA oligonucleotides were studied and compared to the clinically used anticancer drugs cisplatin and carboplatin using both MALDI and ESI mass spectrometric methods. The compound Rh2(O2CCF3)4 exhibits the highest reactivity among the dirhodium compounds, which is comparable to cisplatin, followed by [Rh2(O2CCH3)2(CH3CN)6](BF4)2, and finally Rh2(O2CCH3)4 which is the least reactive. Various dirhodium-oligonucleotide adducts were detected with both MALDI and ESI methods, which involve substitution of different numbers of the original ligands of the given dirhodium compound. ESI MS was found to be a sufficiently soft ionization method for detecting intact metal adducts, and CID MS-MS was useful for detecting weakly bound species such as axial adducts [M+Rh2(O2CCH3)4] and for comparing the relative bond strength between ligands in the metal adduct. A combination of anion exchange HPLC purification and enzymatic digestion studies of the adducts of Rh2(O2CCH3)4 with the 5'-CCTTCAACTCTC oligonucleotide revealed that Rh2(O2CCH3)4 binds to the center or to the ends of the oligonucleotide sequence by displacement of one or two acetate groups. Kinetic products of the type [M+Rh2(O2CCH3)3] obtained from the reaction of Rh2(O2CCH3)4 with 5'-CTCTCAACTTCC were separated by employing both reverse phase and anion exchange HPLC methods. The adduct that involves binding of the dirhodium unit to the exocyclic N4 atom of C5 and the N7 of A6 was found to be most stable whereas other adducts involving binding of C3 or C12 residues are clearly less stable. Reaction of cis-[Rh2(DAP)(O2CCH3)3(CH3OH)](O2CCH3) (DAP = 1,12- diazaperylene) with 5'-CTCTCAACTTCC produced a major adduct in which DAP group intercalates between 6A and 7A in the double stranded adduct with the rhodium atom that is not coordinated to the DAP group forming a covalent bond to the N7 atom of 6A which lends stability to the adduct.

Kang, Mijeong

2005-12-01T23:59:59.000Z

164

OFFGAS GENERATION FROM THE DISPOSITION OF SCRAP PLUTONIUM BY VITRIFICATION SIMULANT TESTS  

SciTech Connect

The Department of Energy Office of Environmental Management is supporting R&D for the conceptual design of the Plutonium Disposition Project at the Savannah River Site in Aiken, SC to reduce the attractiveness of plutonium scrap by fabricating a durable plutonium oxide glass form and immobilizing this form within the high-level waste glass prepared in the Defense Waste Processing Facility. A glass formulation was developed that is capable of incorporating large amounts of actinides as well as accommodating many impurities that may be associated with impure Pu feed streams. The basis for the glass formulation was derived from commercial glasses that had high lanthanide loadings. A development effort led to a Lanthanide BoroSilicate (LaBS) glass that accommodated significant quantities of actinides, tolerated impurities associated with the actinide feed streams and could be processed using established melter technologies. A Cylindrical Induction Melter (CIM) was used for vitrification of the Pu LaBS glass. Induction melting for the immobilization of americium and curium (Am/Cm) in a glass matrix was first demonstrated in 1997. The induction melting system was developed to vitrify a non-radioactive Am/Cm simulant combined with a glass frit. Most of the development of the melter itself was completed as part of that work. This same melter system used for Am/Cm was used for the current work. The CIM system used consisted of a 5 inch (12.7 cm) diameter inductively heated platinum-rhodium (Pt-Rh) containment vessel with a control system and offgas characterization. Scrap plutonium can contain numerous impurities including significant amounts of chlorides, fluorides, sodium, potassium, lead, gallium, chromium, and nickel. Smaller amounts of additional elements can also be present. The amount of chlorides present is unusually high for a melter feed. In commercial applications there is no reason to have chloride at such high concentrations. Because the melter operates at 1400-1475 C, many of the impurities present are extremely volatile. An alternative being considered is to pre-treat the impure PuO{sub 2} by water washing to remove the soluble salts, which would significantly reduce the melter emissions. The disadvantage of the washing alternative is the criticality concerns of using water with plutonium. In this paper, the testing that has been conducted at the Savannah River National Laboratory (SRNL) to demonstrate induction melting of impure plutonium simulants will be described. The work described concentrates on quantification of the gaseous and particulate emissions from the induction melter. The Pt-Rh melter vessel is a cylinder with a conical bottom and a tubular drain as shown in Figure 1. A 5-inch (12.7 cm) diameter CIM was used for all of the emissions tests. A 6-inch (15.24 cm) diameter CIM, which is the size of the full-scale melter, has since been constructed for further testing. The 5-inch CIM is heated by three induction coils: one for the 5 inch cylinder, one for the conical section, and one for the 1/4-inch (6.35 mm) drain tube. The 6-inch CIM is similar except the cylinder heater extends lower and also heats the cone. The induction heating system is manufactured by Ameritherm{trademark}. The heating system is controlled by a PC to maintain a specific heat up profile and then maintain a constant energy input that maintains a constant temperature. The CIM is operated in batch mode where the plutonium simulant and the glass-forming frit are first thoroughly mixed in an attrittor mill, then added to the melter. Hafnium oxide (HfO{sub 2}) is used as a simulant for the radioactive PuO{sub 2}. The melter is heated until the mixture begins to melt at about 1100 C, then completely melts at about 1400-1450 C. This temperature is maintained for about three hours. While the temperature is maintained at {approx} 1400 C, an air bubbler is normally used to promote mixing of the glass-forming frit and the waste simulant.

Zamecnik, J; Patricia Toole, P; David Best, D; Timothy Jones, T; Donald02 Miller, D; Whitney Thomas, W; Vickie Williams, V

2008-03-05T23:59:59.000Z

165

STATISTICAL EVALUATION OF PROCESSING DATA FROM THE RH RU HG MATRIX STUDY  

DOE Green Energy (OSTI)

An evaluation of the statistical significance of Rh, Ru, and Hg on DWPF Sludge Receipt and Adjustment Tank (SRAT) cycle catalytic hydrogen generation and process chemistry was conducted by the Savannah River National Laboratory (SRNL) using a full-factorial experimental design. This test design can identify significant interactions between these three species in addition to individual effects. Statistical modeling of data from the Rh-Ru-Hg matrix study has been completed. Preliminary data and conclusions were given in an earlier report. This final report concludes the work on the Rh-Ru-Hg matrix study. Modeling results are summarized below. Rhodium was found to: Promote increased total hydrogen mass; Promote an increase in the maximum hydrogen generation rate; Promote an increase in the hydrogen generation rate shortly after acid addition; Shorten the elapsed time between acid addition and the maximum hydrogen generation rate; Increase formate loss; Inhibit NO{sub 2} and total NO{sub x} off-gas species formation; and Reduce nitrite-to-nitrate conversion. Ruthenium was found to: Promote increased total hydrogen mass; Promote an increase in the maximum hydrogen generation rate; Promote an increase in the hydrogen generation rate in the second half of the SRAT cycle; Promote an increase in total CO{sub 2} generated; Increase formate loss; Promote NO{sub 2} and total NO{sub x} off-gas species formation; and Reduce nitrite-to-nitrate conversion. Mercury was found to: Inhibit total hydrogen mass produced; Promote an increase in total CO{sub 2} generated; Promote NO{sub 2} off-gas species formation; and Inhibit total NO{sub x} off-gas species formation. Results confirmed qualitative observations that Rh was activating before Ru for hydrogen generation. An interaction between Rh and Ru was present in the model for the total hydrogen generated during the SRAT, perhaps because the total combined contributions from two separate episodes of hydrogen generation. The first episode was dominated by Rh and the second by Ru. Consequently, the linear statistical model was asked to explain more than one phenomenon and included more terms. Mercury did not significantly impact hydrogen generated by either Rh or Ru in models in this study (all tests had Hg {ge} 0.5 wt% in total solids), whereas tests in Sludge Batches 3 and 4 (SB3 and SB4) with and without Hg showed a very significant negative impact from adding Hg. The conclusion is that once a small quantity of Hg is present, the primary inhibiting effect of Hg is in place, and hydrogen generation is relatively insensitive to further increases in total Hg. Any secondary Hg effects were difficult to quantify and model. Mercury was found to be statistically significant, however, as an inhibiting factor for hydrogen generation when modeling was based on the logarithm of the hydrogen generation rate. Only limited statistical evidence was found for non-linearity and quadratic dependence of other SRAT process measures, such as formate loss or total NO{sub x} generation, on the three matrix variables. The interaction term for Ru with Hg, however, appeared in models for total CO{sub 2}, total NO{sub 2}, and total moles of nitrogen-derived off-gas species. A single interaction between Ru and Hg during nitrite destruction could explain all three of these effects in the observed responses. Catalytic decomposition of nitrite ion by formic acid produces CO{sub 2} plus either NO or N{sub 2}O. The vast majority of the NO produced is converted to NO{sub 2}, and NO{sub 2} is the major fraction of the total moles of nitrogen in the off-gas species. Future experimental work related to catalytic hydrogen generation control is expected with regard to minimizing formic acid use through alternative reductants as well as in pursuing mesoporous media for sequestering the catalytically active noble metals to inhibit catalytic hydrogen generation. Two alternative stoichiometric acid equations are also under development. A summary document is in draft form that provides an overview of progress made in understanding ca

Koopman, D

2009-04-17T23:59:59.000Z

166

Transition metal complexes of oxazolinylboranes and cyclopentadienyl-bis(oxazolinyl)borates: Catalysts for asymmetric olefin hydroamination and acceptorless alcohol decarbonylation  

Science Conference Proceedings (OSTI)

The research presented and discussed in this dissertation involves the synthesis of transition metal complexes of oxazolinylboranes and cyclopentadienyl-bis(oxazolinyl)borates, and their application in catalytic enantioselective olefin hydroamination and acceptorless alcohol decarbonylation. Neutral oxazolinylboranes are excellent synthetic intermediates for preparing new borate ligands and also developing organometallic complexes. Achiral and optically active bis(oxazolinyl)phenylboranes are synthesized by reaction of 2-lithio-2-oxazolide and 0.50 equiv of dichlorophenylborane. These bis(oxazolinyl)phenylboranes are oligomeric species in solid state resulting from the coordination of an oxazoline to the boron center of another borane monomer. The treatment of chiral bis(oxazolinyl)phenylboranes with sodium cyclopentadienide provide optically active cyclopentadienyl-bis(oxazolinyl)borates H[PhB(C{sub 5}H{sub 5})(Ox{sup R}){sub 2}] [Ox{sup R} = Ox{sup 4S-iPr,Me2}, Ox{sup 4R-iPr,Me2}, Ox{sup 4S-tBu]}. These optically active proligands react with an equivalent of M(NMe{sub 2}){sub 4} (M = Ti, Zr, Hf) to afford corresponding cyclopentadienyl-bis(oxazolinyl)borato group 4 complexes {PhB(C{sub 5}H{sub 4})(Ox{sup R}){sub 2}}M(NMe{sub 2}){sub 2} in high yields. These group 4 compounds catalyze cyclization of aminoalkenes at room temperature or below, providing pyrrolidine, piperidine, and azepane with enantiomeric excesses up to 99%. Our mechanistic investigations suggest a non-insertive mechanism involving concerted C?N/C?H bond formation in the turnover limiting step of the catalytic cycle. Among cyclopentadienyl-bis(oxazolinyl)borato group 4 catalysts, the zirconium complex {PhB(C{sub 5}H{sub 4})(Ox{sup 4S-iPr,Me2}){sub 2}}Zr(NMe{sub 2}){sub 2} ({S-2}Zr(NMe{sub 2}){sub 2}) displays highest activity and enantioselectivity. Interestingly, {S-2}Zr(NMe{sub 2}){sub 2} also desymmetrizes olefin moieties of achiral non-conjugated aminodienes and aminodiynes during cyclization. The cyclization of aminodienes catalyzed by {S-2}Zr(NMe{sub 2}){sub 2} affords diastereomeric mixture of cis and trans cylic amines with high diasteromeric ratios and excellent enantiomeric excesses. Similarly, the desymmetrization of alkyne moieties in {S-2}Zr(NMe{sub 2}){sub 2}-catalyzed cyclization of aminodiynes provides corresponding cyclic imines bearing quaternary stereocenters with enantiomeric excesses up to 93%. These stereoselective desymmetrization reactions are significantly affected by concentration of the substrate, temperature, and the presence of a noncyclizable primary amine. In addition, both the diastereomeric ratios and enantiomeric excesses of the products are markedly enhanced by N-deuteration of the substrates. Notably, the cationic zirconium-monoamide complex [{S-2}Zr(NMe{sub 2})][B(C{sub 6}F{sub 5}){sub 4}] obtained from neutral {S-2}Zr(NMe{sub 2}){sub 2} cyclizes primary aminopentenes providing pyrrolidines with S-configuration; whereas {S-2}Zr(NMe{sub 2}){sub 2} provides R-configured pyrrolidines. The yttrium complex {S-2}YCH{sub 2}SiMe{sub 3} also affords S-configured pyrrolidines by cyclization of aminopentenes, however the enantiomeric excesses of products are low. An alternative optically active yttrium complex {PhB(C{sub 5}H{sub 4})(Ox{sup 4S-tBu}){sub 2}}YCH{sub 2}SiMe{sub 3} ({S-3}YCH{sub 2}SiMe{sub 3}) is synthesized, which displays highly enantioselective in the cyclization of aminoalkenes at room temperature affording S-configured cyclic amines with enantiomeric excesses up to 96%. A noninsertive mechanism involving a six-membered transition state by a concerted C?N bond formation and N?H bond cleavage is proposed for {S-3}YCH{sub 2}SiMe{sub 3} system based on the kinetic, spectroscopic, and stereochemical features. In the end, a series of bis- and tris(oxazolinyl)borato iridium and rhodium complexes are synthesized with bis(oxazolinyl)phenylborane [PhB(Ox{sup Me2}){sub 2}]{sub n}, tris(oxazolinyl)borane [B(Ox{sup Me2}){sub 3}]n, and tris(4,4-dimethyl-2-oxazolinyl)phenylborate [To{sup M}]{sup ?}. All these new an

Manna, Kuntal [Ames Laboratory

2012-12-17T23:59:59.000Z

167

DWPF CATALYTIC HYDROGEN GENERATION PROGRAM - REVIEW OF CURRENT STATUS  

DOE Green Energy (OSTI)

Significant progress has been made in the past two years in improving the understanding of acid consumption and catalytic hydrogen generation during the Defense Waste Processing Facility (DWPF) processing of waste sludges in the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME). This report reviews issues listed in prior internal reviews, describes progress with respect to the recommendations made by the December 2006 external review panel, and presents a summary of the current understanding of catalytic hydrogen generation in the DWPF Chemical Process Cell (CPC). Noble metals, such as Pd, Rh, and Ru, are historically known catalysts for the conversion of formic acid into hydrogen and carbon dioxide. Rh, Ru, and Pd are present in the DWPF SRAT feed as by-products of thermal neutron fission of {sup 235}U in the original waste. Rhodium appears to become most active for hydrogen as the nitrite ion concentration becomes low (within a factor of ten of the Rh concentration). Prior to hydrogen generation, Rh is definitely active for nitrite destruction to N{sub 2}O and potentially active for nitrite to NO formation. These reactions are all consistent with the presence of a nitro-Rh complex catalyst, although definite proof for the existence of this complex during Savannah River Site (SRS) waste processing does not exist. Ruthenium does not appear to become active for hydrogen generation until nitrite destruction is nearly complete (perhaps less nitrite than Ru in the system). Catalytic activity of Ru during nitrite destruction is significantly lower than that of either Rh or Pd. Ru appears to start activating as Rh is deactivating from its maximum catalytic activity for hydrogen generation. The slow activation of the Ru, as inferred from the slow rate of increase in hydrogen generation that occurs after initiation, may imply that some species (perhaps Ru itself) has some bound nitrite on it. Ru, rather than Rh, is primarily responsible for the hydrogen generation in the SME cycle when the hydrogen levels are high enough to be noteworthy. Mercury has a role in catalytic hydrogen generation. Two potentially distinct roles have been identified. The most dramatic effect of Hg on hydrogen generation occurs between runs with and without any Hg. When a small amount of Hg is present, it has a major inhibiting effect on Rh-catalyzed H{sub 2} generation. The Rh-Ru-Hg matrix study showed that increasing mercury from 0.5 to 2.5 wt% in the SRAT receipt total solids did not improve the inhibiting effect significantly. The next most readily identified role for Hg is the impact it has on accelerating NO production from nitrite ion. This reaction shifts the time that the ideal concentration of nitrite relative to Rh occurs, and consequently causes the most active nitro-Rh species to form sooner. The potential consequences of this shift in timing are expected to be a function of other factors such as amount of excess acid, Rh concentration, etc. Graphical data from the Rh-Ru-Hg study suggested that Hg might also be responsible for partially inhibiting Ru-catalysis initially, but that the inhibition was not sustained through the SRAT and SME cycles. Continued processing led to a subsequent increase in hydrogen generation that was often abrupt and that frequently more than doubled the hydrogen generation rate. This phenomenon may have been a function of the extent of Hg stripping versus the initial Ru concentration in these tests. Palladium is an active catalyst, and activates during (or prior to) nitrite destruction to promote N{sub 2}O formation followed by a very small amount of hydrogen. Pd then appears to deactivate. Data to date indicate that Pd should not be a species of primary concern relative to Rh and Ru for hydrogen generation. Pd was a very mild catalyst for hydrogen generation compared to Rh and Ru in the simulated waste system. Pd was comparable to Rh in enhancing N{sub 2}O production when present at equal concentration. Pd, however, is almost always present at less than a quarter of the Rh concentration in S

Koopman, D.

2009-07-10T23:59:59.000Z

168

97e Intermediate Temperature Catalytic Reforming of Bio-Oil for Distributed Hydrogen Production  

Science Conference Proceedings (OSTI)

With the world's energy demands rapidly increasing, it is necessary to look to sources other than fossil fuels, preferably those that minimize greenhouse emissions. One such renewable source of energy is biomass, which has the added advantage of being a near-term source of hydrogen. While there are several potential routes to produce hydrogen from biomass thermally, given the near-term technical barriers to hydrogen storage and delivery, distributed technologies such that hydrogen is produced at or near the point of use are attractive. One such route is to first produce bio-oil via fast pyrolysis of biomass close to its source to create a higher energy-density product, then ship this bio-oil to its point of use where it can be reformed to hydrogen and carbon dioxide. This route is especially well suited for smaller-scale reforming plants located at hydrogen distribution sites such as filling stations. There is also the potential for automated operation of the conversion system. A system has been developed for volatilizing bio-oil with manageable carbon deposits using ultrasonic atomization and by modifying bio-oil properties, such as viscosity, by blending or reacting bio-oil with methanol. Non-catalytic partial oxidation of bio-oil is then used to achieve significant conversion to CO with minimal aromatic hydrocarbon formation by keeping the temperature at 650 C or less and oxygen levels low. The non-catalytic reactions occur primarily in the gas phase. However, some nonvolatile components of bio-oil present as aerosols may react heterogeneously. The product gas is passed over a packed bed of precious metal catalyst where further reforming as well as water gas shift reactions are accomplished completing the conversion to hydrogen. The approach described above requires significantly lower catalyst loadings than conventional catalytic steam reforming due to the significant conversion in the non-catalytic step. The goal is to reform and selectively oxidize the bio-oil and catalyze the water gas shift reaction without catalyzing methanation or oxidation of CO and H{sub 2}, thus attaining equilibrium levels of H{sub 2}, CO, H{sub 2}O, and CO{sub 2} at the exit of the catalyst bed. Experimental Bio-oil (mixed with varied amounts of methanol to reduce the viscosity and homogenize the bio-oil) or selected bio-oil components are introduced at a measured flow rate through the top of a vertical quartz reactor which is heated using a five zone furnace. The ultrasonic nozzle used to feed the reactants allows the bio-oil to flow down the center of the reactor at a low, steady flow rate. Additionally, the fine mist created by the nozzle allows for intimate mixing with oxygen and efficient heat transfer, providing optimal conditions to achieve high conversion at relatively low temperatures in the non-catalytic step thus reducing the required catalyst loading. Generation of the fine mist is especially important for providing good contact between non-volatile bio-oil components and oxygen. Oxygen and helium are also delivered at the top of the reactor via mass flow meters with the amount of oxygen being varied to maximize the yields of H{sub 2} and CO and the amount of helium being adjusted such that the gas phase residence time in the hot zone is {approx}0.3 and {approx}0.45 s for bio-oil and methanol experiments, respectively. A catalyst bed can be located at the bottom of the reactor tube. To date, catalyst screening experiments have used Engelhard noble metal catalysts. The catalysts used for these experiments were 0.5 % rhodium, ruthenium, platinum, and palladium (all supported on alumina). Experiments were performed using pure alumina as well. Both the catalyst type and the effect of oxygen and steam on the residual hydrocarbons and accumulated carbon containing particulates were investigated. The residence time before the catalyst is varied to determine the importance of the non-catalytic step and its potential effect on the required catalyst loading. Non-catalytic experiments (primarily homogeneous cracking) use a bed of quartz p

Marda, J. R.; Dean, A. M.; Czernik, S.; Evans, R. J.; French, R.; Ratcliff, M.

2008-01-01T23:59:59.000Z