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The Isosynthesis

Description: From Preface: "The paper contains data on the development of the catalyst for the isosynthesis, on the effect of temperature and pressure of operation, and on the composition of the products of the reaction. In the last section, experimental evidence and speculations concerning the mechanisms of the isosynthesis are discussed."
Date: 1950
Creator: Pichler, Helmut & Ziesecke, Karl-Heinz
Partner: UNT Libraries Government Documents Department

Interstitial Compounds as Fuel Cell Catalysts: Their Preparative Techniques and Electrochemical Testing

Description: From Introduction: "This report is a consolidated account of the total program with the exception of work done at Tyco Laboratories. Only a summary of Tyco's findings regarding the activity of the materials has been included in this report since a comprehensive report on their work will appear separately."
Date: unknown
Creator: Akhtar, S.; Grein, C. T. & Bienstock, D.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: September 23, 2013
Creator: Gerber, Mark A.; Gray, Michel J. & Thompson, Becky L.
Partner: UNT Libraries Government Documents Department

Synthetic Liquid Fuels from Hydrogenation of Carbon Monoxide: Cobalt and Iron Catalysts for the Fischer-Tropsch Synthesis: Preparation and Characterization of Catalysts, Synthesis Tests, and Reaction Mechanism (Part 2 of Two Parts)

Description: From Summary: "This bulletin contains extensive data on catalytic and other properties of iron carbides, nitrides, and carbonitrides. The appendix describes some equipment and techniques developed in the course of this work and gives a detailed account of the application of magnetic measurements to studies of ferromagnetic catalysts."
Date: 1959
Creator: Shultz, J. F.; Hofer, L. J. E.; Cohn, E. M.; Stein, K. C. & Anderson, R. B.
Partner: UNT Libraries Government Documents Department

Heinz Heinemann. The Berkeley Years (1978-1993)

Description: Heinz Heineman came to Berkeley in 1978 and stayed there for 15 years. This was the time of the energy crisis and we did not have anybody like him who had such a tremendous industrial experience with oil and coal conversion technology and science. He was interested in the conversion of coal to gaseous molecules and our studies with model catalysts appealed to him and attracted him. In a way, Heinz Heineman was bigger than life, since he played such a seminal role in the history of American catalysis science.
Date: August 27, 2009
Creator: Coble, Inger M.
Partner: UNT Libraries Government Documents Department

Nanostructured carbide catalysts for the hydrogen economy

Description: The above quote, taken from the executive summary of the Report from the US DOE Basic Energy Sciences Workshop held August 6–8, 2007,[1] places in context the research carried out at the University of California, Santa Barbara, which is reported in this document. The enormous impact of heterogeneous catalysis is exemplified by the Haber process for the synthesis of ammonia, which consumes a few % of the world’s energy supply and natural gas, and feeds as many as a third of the world’s population. While there have been numerous advances in understanding the process,[2] culminating in the awarding of the Nobel Prize to Gerhard Ertl in 2007, it is interesting to note that the catalysts themselves have changed very little since they were discovered heuristically in the the early part of the 20th century. The thesis of this report is that modern materials chemistry, with all the empirical knowledge of solid state chemistry, combined with cutting edge structural tools, can help develop and better heterogeneous catalysis. The first part of this report describes research in the area of early transition metal carbides (notably of Mo and W), potentially useful catalysts for water gas shift (WGS) and related reactions of use to the hydrogen economy. Although these carbides have been known to be catalytically useful since the 1970s,[3] further use of these relatively inexpensive materials have been plagued by issues of low surface areas and ill-defined, and often unreactive surfaces, in conjunction with deactivation. We have employed for the first time, a combination of constant-wavelength and time-of-flight neutron scattering, including a total scattering analysis of the latter data, to better understand what happens in these materials, in a manner that for the first time, reveals surface graphitic carbon in these materials in a quantitative manner. Problems of preparation, surface stability, and ...
Date: July 21, 2008
Creator: Ram Seshadri, Susannah Scott, Juergen Eckert
Partner: UNT Libraries Government Documents Department

Catalyst technology roadmap report

Description: This report outlines the future technology needs of the Chemical Industry in the area of catalysis and is a continuation of the process that produced the report Technology Vision 2020: The U.S. Chemical Industry and the Council for Chemical Research`s (CCR) Chemical Synthesis Team follow-up work in chemical synthesis. Vision 2020 developed a 25-year vision for the chemical industry and outlined the challenges to be addressed in order to achieve this vision. This report, which outlines the catalysis technology roadmap, is based on the output of the CCR`s Chemical Synthesis Team, plus a workshop held March -20-21, 1997, which included about 50 participants, with catalysis experts from industry, academia, and government. It is clear that all participants view catalysis as a fundamental driver to the 0274 economic and environmental viability of the chemical industry. Advances in catalytic science and technology are among the most crucial challenges to achieving the goals of the chemical industry advanced in Vision 2020.
Date: June 1, 1997
Creator: Jackson, N.B.
Partner: UNT Libraries Government Documents Department

Catalytic Membrane Sensors

Description: The proposed "catalytic membrane sensor" (CMS) was developed to generate a device which would selectively identify a specific reagent in a complex mixture of gases. This was to be accomplished by modifying an existing Hz sensor with a series of thin films. Through selectively sieving the desired component from a complex mixture and identifying it by decomposing it into Hz (and other by-products), a Hz sensor could then be used to detect the presence of the select component. The proposed "sandwich-type" modifications involved the deposition of a catalyst layered between two size selective sol-gel layers on a Pd/Ni resistive Hz sensor. The role of the catalyst was to convert organic materials to Hz and organic by-products. The role of the membraneo was to impart both chemical specificity by molecukir sieving of the analyte and converted product streams, as well as controlling access to the underlying Pd/Ni sensor. Ultimately, an array of these CMS elements encompassing different catalysts and membranes were to be developed which would enable improved selectivity and specificity from a compiex mixture of organic gases via pattern recognition methodologies. We have successfully generated a CMS device by a series of spin-coat deposited methods; however, it was determined that the high temperature required to activate the catalyst, destroys the sensor.
Date: December 1, 1998
Creator: Boyle, T.J.; Brinker, C.J.; Gardner, T.J.; Hughes, R.C. & Sault, A.G.
Partner: UNT Libraries Government Documents Department

Enantioselective Catalysis of the Aza-Cope Rearrangement by a Chiral Supramolecular Assembly

Description: The chiral supramolecular catalyst Ga{sub 4}L{sub 6} [L = 1,5-bis(2,3-dihydroxybenzoylamino)naphthalene] is a molecular tetrahedron that catalyzes the 3-aza-Cope rearrangement of allyl enammonium cations. This catalysis is accomplished by preorganizing the substrate in a reactive conformation within the host. This work demonstrates that through the use of enantiopure assembly, its chiral cavity is capable of catalyzing the 3-aza-Cope rearrangement enantioselectively, with yields of 21-74% and enantiomeric excesses from 6 to 64% at 50 C. At lower temperatures, the enantioselectivity improved, reaching 78% ee at 5 C. This is the highest enantioselectivity to date induced by the chiral cavity of a supramolecular assembly.
Date: July 29, 2009
Creator: Brown, Casey J.; Bergman, Robert G. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department

Computational Studies of Selected Ruthenium Catalysis Reactions.

Description: Computational techniques were employed to investigate pathways that would improve the properties and characteristics of transition metal (i.e., ruthenium) catalysts, and to explore their mechanisms. The studied catalytic pathways are particularly relevant to catalytic hydroarylation of olefins. These processes involved the +2 to +3 oxidation of ruthenium and its effect on ruthenium-carbon bond strengths, carbon-hydrogen bond activation by 1,2-addition/reductive elimination pathways appropriate to catalytic hydrogen/deuterium exchange, and the possible intermediacy of highly coordinatively unsaturated (e.g., 14-electron) ruthenium complexes in catalysis. The calculations indicate a significant decrease in the Ru-CH3 homolytic bond dissociation enthalpy for the oxidation of TpRu(CO)(NCMe)(Me) to its RuIII cation through both reactant destabilization and product stabilization. This oxidation can thus lead to the olefin polymerization observed by Gunnoe and coworkers, since weak RuIII-C bonds would afford quick access to alkyl radical species. Calculations support the experimental proposal of a mechanism for catalytic hydrogen/deuterium exchange by a RuII-OH catalyst. Furthermore, calculational investigations reveal a probable pathway for the activation of C-H bonds that involves phosphine loss, 1,2-addition to the Ru-OH bond and then reversal of these steps with deuterium to incorporate it into the substrate. The presented results offer the indication for the net addition of aromatic C-H bonds across a RuII-OH bond in a process that although thermodynamically unfavorable is kinetically accessible. Calculations support experimental proposals as to the possibility of binding of weakly coordinating ligands such as dinitrogen, methylene chloride and fluorobenzene to the "14-electron" complex [(PCP)Ru(CO)]+ in preference to the formation of agostic Ru-H-C interactions. Reactions of [(PCP)Ru(CO)(1-ClCH2Cl)][BAr'4] with N2CHPh or phenylacetylene yielded conversions that are exothermic to both terminal carbenes and vinylidenes, respectively, and then bridging isomers of these by C-C bond formation resulting from insertion into the Ru-Cipso bond of the phenyl ring of PCP. The QM/MM and DFT calculations on full complexes ...
Date: December 2007
Creator: Barakat, Khaldoon A.
Partner: UNT Libraries

Simulating Nonuniform Properties in Polymer-Electrolyte FuelCells

Description: In this transaction, results from mathematical, pseudo 2-D simulations are shown for four different thickness distributions of both the membrane and cathode catalyst layer. The results and subsequent analysis clearly demonstrate that the position along the gas channel is more important than the local thickness variations, especially for the membrane.
Date: July 1, 2006
Creator: Weber, A.Z. & Newman, J.
Partner: UNT Libraries Government Documents Department

ISHHC XIII International Symposium on the Relations betweenHomogeneous and Heterogeneous Catalysis

Description: The International Symposium on Relations between Homogeneous and Heterogeneous Catalysis (ISHHC) has a long and distinguished history. Since 1974, in Brussels, this event has been held in Lyon, France (1977), Groeningen, The Netherlands (1981); Asilomar, California (1983); Novosibirsk, Russia (1986); Pisa, Italy (1989); Tokyo, Japan (1992); Balatonfuered, Hungary (1995); Southampton, United Kingdom (1999); Lyon, France (2001); Evanston, Illinois (2001) and Florence, Italy (2005). The aim of this international conference in Berkeley is to bring together practitioners in the three fields of catalysis, heterogeneous, homogeneous and enzyme, which utilize mostly nanosize particles. Recent advances in instrumentation, synthesis and reaction studies permit the nanoscale characterization of the catalyst systems, often for the same reaction, under similar experimental conditions. It is hoped that this circumstance will permit the development of correlations of these three different fields of catalysis on the molecular level. To further this goal we aim to uncover and focus on common concepts that emerge from nanoscale studies of structures and dynamics of the three types of catalysts. Another area of focus that will be addressed is the impact on and correlation of nanosciences with catalysis. There is information on the electronic and atomic structures of nanoparticles and their dynamics that should have importance in catalyst design and catalytic activity and selectivity.
Date: June 11, 2007
Creator: Somorjai (Ed.), G.A.
Partner: UNT Libraries Government Documents Department

Effects of Curvature on Asymmetric Steady States in Catalyst Particles

Description: The effects of curvature on steady states of chemical catalytic reactions are investigated by studying the cases of the catalytic particle being a spherical or cylindrical shell. Existence and stability of solutions are studied. It is shown that the solutions converge to the solutions for the catalytic slab when the curvature goes to 0 in each case.
Date: February 1981
Creator: Lucier, Bradley J.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: October 1, 2010
Creator: Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O.; White, J. F.; Rummel, Becky L. & Stevens, Don J.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: October 1, 2011
Creator: Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O. & Rummel, Becky L.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: November 1, 2012
Creator: Gerber, Mark A.; Gray, Michel J.; Albrecht, Karl O. & Thompson, Becky L.
Partner: UNT Libraries Government Documents Department

Chemical Mechanism of the Catalytic Subunit of Camp-Dependent Protein Kinase: Methods for Determining the Primary ¹⁸O Isotope Effects Using the Remote Label Technique

Description: A description of the nature of the transition state structure for phosphoryl transfer in the cAPK reaction requires a measurement of the primary 180 isotope effect at the serine hydroxyl acceptor. Since it is difficult to obtain primary 180 isotope effect directly, the 15N/1 4N ratio of the a-amine of the C-terminal glycine in the peptide Leu Arg-Lys-Ala-Ser-Leu-Gly (when serine is phosphorylated) was used to represent on the phosphorylation at serine. 15N Glycine, ' 4N-Glycine and 180 serine were synthesized and used to synthesize two peptides, one containing 1 80-serine/' 5 N glycine and second 1 60-serine/1 4N-glycine. Methods were developed for hydrolyzing the peptides and quantitatively isolating glycine. Partitioning results suggest that catalytic rate was slow compare to substrate dissociation. The 180 primary isotope effect will be determined in the near future using the method developed herein.
Date: December 1991
Creator: Chen, Gang
Partner: UNT Libraries