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Bibliography of Pressure Hydrogenation (In Three Parts): [Part] 1. Review and Compilation of the Literature on Pressure Hydrogenation of Liquid and Solid Carbonaceous Materials

Description: From Introduction: This review contains abstracts of the technical literature and patents dealing material application of the Bergius and related processes for the hydrogenation, under greater than atmospheric pressures, of liquid and solid carbonaceous materials such as coal, lignite, their distillation and extraction products, pitches and tars, and petroleum and its distillation residues."
Date: 1950
Creator: Wiley, J. L. & Anderson, H. C.
Partner: UNT Libraries Government Documents Department

Hydrogenation of Coal in the Batch Autoclave

Description: From Introduction: "This bulletin presents results of laboratory experiments performed between 1944 and 1956, which have particularly sought to improve the conversion of coal to liquids in small batch-type high-pressure reactors (autoclaves)."
Date: unknown
Creator: Hawk, C. O. & Hiteshue, R. W.
Partner: UNT Libraries Government Documents Department

Hydrogenation of Coal and Tar

Description: From Abstract: "This bulletin traces the development of high-pressure, coal and tar hydrogenation technology, based on intensive review of the pertinent literature. The bulletin was written as a part of the Bureau of Mines research program on synthetic liquid fuels. It covers the history and economics of the process; the chemical aspect of hydrogenation of coal, tar, and middle oil; the engineer aspect of converting coal and tar to liquid fuels, principally gasoline; and the equipment of the process."
Date: unknown
Creator: Wu, W. R. K. & Storch, H. H.
Partner: UNT Libraries Government Documents Department

Physical Chemistry of the Fischer-Tropsch Synthesis

Description: From Summary: "This paper summarizes the results of physicochemical studies of the Fischer-Tropsch synthesis (the catalytic hydrogenation of carbon monoxide) undertaken by the Federal Bureau of Mines as part of its program on improving processes for producing liquid fuels from coal."
Date: 1959
Creator: Anderson, R. B.; Shultz, J. F.; Hofer, L. J. E. & Storch, H. H.
Partner: UNT Libraries Government Documents Department

Thermal Solution and Hydrogenation of Green River Oil Shale: Experimental Investigations and Bibliography

Description: From Introduction: "This so-called thermal-solution process and a modification of it, wherein the conversion is carried out under a high partial pressure of hydrogen, have been studied at the Petroleum and Oil-Shale Experiment Station, Laramie, Wyo., to determine their applicability to Green River oil shale. The results of this work are presented in this report."
Date: 1953
Creator: Jensen, H. B.; Barnet, W. I. & Murphy, W. I. R.
Partner: UNT Libraries Government Documents Department

Hydrogenation of Petroleum and Lignite Tar Distillates

Description: Report issued by the U.S. Bureau of Mines regarding the operation of the Coal Hydrogenation Demonstration Plant in Missouri. This report summarizes the operating experience gained and the characteristics of the products created during operation of the plant. The report includes graphs, tables, and illustrations.
Date: April 1950
Creator: Clarke, E. A.; Chaffee, C. C. & Hirst, L. L.
Partner: UNT Libraries Government Documents Department

Characterization of Tar Acids from Coal-Hydrogenation Oils

Description: From Introduction: "The purpose of this investigation was to separate and identify as many of the principal phenolic compounds produced by the mild hydrogenation of Pittsburgh-bed (Bruceton) coal as possible and to determine with the greatest possible accuracy the proportions in which they are present."
Date: 1950
Creator: Woolfolk, E. O.; Golumbic, C.; Friedel, R. A.; Orchin, Milton & Storch, H. H.
Partner: UNT Libraries Government Documents Department

Modification of Graphene Properties: Electron Induced Reversible Hydrogenation, Oxidative Etching and Layer-by-layer Thinning

Description: In this dissertation, I present the mechanism of graphene hydrogenation via three different electron sources: scanning electron microscopy, e-beam irradiation and H2 and He plasma irradiation. in each case, hydrogenation occurs due to electron impact fragmentation of adsorbed water vapor from the sample preparation process. in the proposed model, secondary and backscattered electrons generated from incident electron interactions with the underlying silicon substrate are responsible for the dissociation of water vapor. Chemisorbed H species from the dissociation are responsible for converting graphene into hydrogenated graphene, graphane. These results may lead to higher quality graphane films having a larger band gap than currently reported. in addition, the dissertation presents a novel and scalable method of controllably removing single atomic planes from multi-layer graphene using electron irradiation from an intense He plasma under a positive sample bias. As the electronic properties or multi-layer graphene are highly dependent on the number of layers, n, reducing n in certain regions has many benefits. for example, a mask in conjunction with this thinning method could be used for device applications.
Date: May 2012
Creator: Jones, Jason David
Partner: UNT Libraries

Special Equipment in the Coal-Hydrogenation Demonstration Plant

Description: Report issued by the Bureau of Mines over the equipment used in coal hydrogenation demonstration plants. Detailed descriptions of the equipment and machinery are presented. This report includes tables, illustrations, and photographs.
Date: January 1950
Creator: Markovits, J. A.; Braun, K. C.; Donovan, J. T. & Sandaker, J. H.
Partner: UNT Libraries Government Documents Department

Mechanistic Studies at the Interface Between Organometallic Chemistry and Homogeneous Catalysis

Description: Mechanistic Studies at the Interface Between Organometallic Chemistry and Homogeneous Catalysis Charles P. Casey, Principal Investigator Department of Chemistry, University of Wisconsin - Madison, Madison, Wisconsin 53706 Phone 608-262-0584 FAX: 608-262-7144 Email: casey@chem.wisc.edu http://www.chem.wisc.edu/main/people/faculty/casey.html Executive Summary. Our goal was to learn the intimate mechanistic details of reactions involved in homogeneous catalysis and to use the insight we gain to develop new and improved catalysts. Our work centered on the hydrogenation of polar functional groups such as aldehydes and ketones and on hydroformylation. Specifically, we concentrated on catalysts capable of simultaneously transferring hydride from a metal center and a proton from an acidic oxygen or nitrogen center to an aldehyde or ketone. An economical iron based catalyst was developed and patented. Better understanding of fundamental organometallic reactions and catalytic processes enabled design of energy and material efficient chemical processes. Our work contributed to the development of catalysts for the selective and mild hydrogenation of ketones and aldehydes; this will provide a modern green alternative to reductions by LiAlH4 and NaBH4, which require extensive work-up procedures and produce waste streams. (C5R4OH)Ru(CO)2H Hydrogenation Catalysts. Youval Shvo described a remarkable catalytic system in which the key intermediate (C5R4OH)Ru(CO)2H (1) has an electronically coupled acidic OH unit and a hydridic RuH unit. Our efforts centered on understanding and improving upon this important catalyst for reduction of aldehydes and ketones. Our mechanistic studies established that the reduction of aldehydes by 1 to produce alcohols and a diruthenium bridging hydride species occurs much more rapidly than regeneration of the ruthenium hydride from the diruthenium bridging hydride species. Our mechanistic studies require simultaneous transfer of hydride from ruthenium to the aldehyde carbon and of a proton from the CpOH unit to the aldehyde oxygen and support reduction of the aldehyde without its prior coordination to ruthenium. Another important ...
Date: November 14, 2012
Creator: Casey, Charles P.
Partner: UNT Libraries Government Documents Department

Structure and Reactions of Carbon and Hydrogen on Ru(0001): A Scanning Tunneling Microscopy Study

Description: The interaction between carbon and hydrogen atoms on a Ru(0001) surface was studied using scanning tunneling microscopy (STM), Density Functional Theory (DFT) and STM image calculations. Formation of CH species by reaction between adsorbed H and C was observed to occur readily at 100 K. When the coverage of H increased new complexes of the form CH+nH (n = 1, 2 and 3) were observed. These complexes, never observed before, might be precursors for further hydrogenation reactions. DFT analysis reveals that a considerable energy barrier exists for the CH+H {yields} CH{sub 2} reaction.
Date: September 9, 2008
Creator: Shimizu, Tomoko K.; Mugarza, Aitor; Cerda, Jorge & Salmeron, Miquel
Partner: UNT Libraries Government Documents Department

Induced biochemical interactions in immature and biodegraded heavy crude oils

Description: Studies in which selective chemical markers have been used to explore the mechanisms by which biocatalysts interact with heavy crude oils have shown that the biochemical reactions follow distinct trends. The term biocatalyst refers to a group of extremophilic microorganisms which, under the experimental conditions used, interact with heavy crude oils to (1) cause a redistribution of hydrocarbons, (2) cause chemical changes in oil fractions containing sulfur compounds and lower the sulfur content, (3) decrease organic nitrogen content, and (4) decrease the concentration of trace metals. Current data indicate that the overall effect is due to simultaneous reactions yielding products with relatively higher concentration of saturates and lower concentrations of aromatics and resins. The compositional changes depend on the microbial species and the chemistry of the crudes. Economic analysis of a potential technology based on the available data indicate that such a technology, used in a pre-refinery mode, may be cost efficient and promising. In the present paper, the background of oil biocatalysis and some recent results will be discussed.
Date: November 1, 1998
Creator: Premuzic, E.T.; Lin, M.S.; Bohenek, M.; Joshi-Tope, G.; Shelenkova, L. & Zhou, W.M.
Partner: UNT Libraries Government Documents Department

Bibliography of the Fischer-Tropsch Synthesis and Related Processes: (In Two Parts) I. Review and Compilation of the Literature on the Production of Synthetic Liquid Fuels and Chemicals by the Hydrogenation of Carbon Monoxide

Description: Report containing abstracts of the technical literature and patents dealing with the history, development, and commercial application of the Fischer-Tropsch synthesis and related processes for the hydrogenation of carbon monoxide and the production of synthetic fuels and chemicals.
Date: 1954
Creator: Anderson, H. C.; Wiley, J. L. & Newell, A.
Partner: UNT Libraries Government Documents Department

Semiempirical study of hydrogen addition to single-walled carbon nanotubes

Description: Single-walled carbon nanotube models have been constructed by insertion of 10-carbon bracelets into C{sub 70} to form C{sub 90} and C{sub 120}. Semiempirical heats of vicinal hydrogenation along the sides of the tubes are {approximately}40 kcal/mol more endothermic (less stable) than addition to the endcaps. Based on the similarity of the endcaps to C{sub 60}, hydrogenation of nanotubes is estimated to be approximately thermoneutral; therefore, only relatively high energy dienes or other species are likely to yield stable addended products.
Date: July 1, 1995
Creator: Cahill, P.A.
Partner: UNT Libraries Government Documents Department

Dynamics of Propane in Silica Mesopores Formed upon PropyleneHydrogenation over Pt Nanoparticles by Time-Resolved FT-IRSpectroscopy

Description: Propylene hydrogenation over Pt nanoparticles supported onmesoporous silica type SBA-15 was monitored by time-resolved FT-IRspectroscopy at 23 ms resolution using short propylene gas pulses thatjoined a continuous flow of hydrogen in N2 (1 atm total pressure).Experiments were conducted in the temperature range 323-413 K. Propanewas formed within 100 milliseconds or faster. The CH stretching regionrevealed distinct bands for propane molecules emerging inside thenanoscale channels of the silica support. Spectral analysis gave thedistribution of the propane product between support and surrounding gasphase as function of time. Kinetic analysis showed that the escape ofpropane molecules from the channels occurred within hundreds ofmilliseconds (3.1 + 0.4 s-1 at 383 K). A steady state distribution ofpropane between gas phase and mesoporous support is established as theproduct is swept from the catalyst zone by the continuous flow ofhydrogen co-reactant. This is the first direct spectroscopic observationof emerging products of heterogeneous catalysis on nanoporous supportsunder reaction conditions.
Date: January 31, 2007
Creator: Waslylenko, Walter & Frei, Heinz
Partner: UNT Libraries Government Documents Department

Novel approaches concerning catalyst deactivation. Final report, July 1, 1982-December 31, 1983

Description: A complete analysis is presented of a model originally suggested by Wei and Wei (J. Wei and R.G. Wei, Metal Deposition Profiles in Hydro-Demetallation, Chem. Eng. Comm., 13, 251, 1982) to model the behavior of catalysts during hydro-demetallation of coal derived liquids. This model does not take into account the fact that as hydro-demetallation reaction precedes the deposited metals deactivate the catalyst and destroy its pore structure. It was felt however that a complete analysis of this model was needed since it is amenable to analytical solutions, describes the initial state of more complete deactivation models and qualitatively predicts all the different metal profiles one expects to find on spent (deactivated) catalysts. The investigators have also presented here the set of equations describing a more complete and realistic hydro-demetallation model. The analysis of this model, however has yet to be completed and will be presented later as an addendum to this report. 7 references, 7 figures, 2 tables.
Date: March 1, 1984
Creator: Tsotsis, T.T.
Partner: UNT Libraries Government Documents Department

Wall pressure exerted by hydrogenation of sodium aluminum hydride.

Description: Wall pressure exerted by the bulk expansion of a sodium aluminum hydride bed was measured as a function of hydrogen content. A custom apparatus was designed and loaded with sodium alanates at densities of 1.0, 1.1, and 1.16 g/cc. Four complete cycles were performed to identify variations in measured pressure. Results indicated poor correlation between exerted pressure and hydrogen capacity of the sodium alanate beds. Mechanical pressure due to the hydrogenation of sodium alanates does not influence full-scale system designs as it falls within common design factors of safety. Gas pressure gradients within the porous solid were identified and may limit reaction rates, especially for high aspect ratio beds.
Date: June 1, 2009
Creator: Perras, Yon E.; Dedrick, Daniel E. & Zimmerman, Mark D.
Partner: UNT Libraries Government Documents Department

Direct Observation of the Kinetically Relevant Site of CO Hydrogenation on Supported Ru Catalyst at 700 K by Time-Resolved FT-IR Spectroscopy

Description: Time-resolved FT-IR spectra of carbon monoxide hydrogenation over alumina-supported ruthenium particles were recorded on themillisecond time scale at 700 K using pulsed release of CO and a continuous flow of H2/N2 (ratio 0.067 or 0.15, 1 atm total pressure). Adsorbed carbon monoxide was detected along with gas phase products methane (3016 and 1306 cm-1), water (1900 +- 1300 cm-1), and carbon dioxide (2348 cm-1). Aside from adsorbed CO, no other surface species were observed. The rate of formation of methane is 2.5 +- 0.4 s-1 and coincides with the rate of carbon dioxide growth (3.4 +- 0.6 s-1), thus indicating that CH4 and CO2 originate from a common intermediate. The broad band of adsorbed carbon monoxide has a maximum at 2010 cm-1 at early times (36 ms) that shifts gradually to 1960 cm-1 over a period of 3 s as a result of the decreasing surface concentration of CO. Kinetic analysis of the adsorbed carbon monoxide reveals that surface sites absorbing at the high frequency end of the infrared band are temporally linked to gas phase product growth. Specifically, a (linear) CO site at 2026 cm-1 decays with a rate constant of 2.9 +- 0.1 s-1, which coincides with the rise constant of CH4. This demonstrates that the linear CO site at 2026 cm-1 is the kinetically most relevant one for the rate-determining CO dissociation step under reaction conditions at 700 K.
Date: June 4, 2008
Creator: Frei, Heinz; Wasylenko, Walter & Frei, Heinz
Partner: UNT Libraries Government Documents Department

ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE

Description: One of the challenges of implementing the hydrogen economy is finding a suitable solid H{sub 2} storage material. Aluminium (alane, AlH{sub 3}) hydride has been examined as a potential hydrogen storage material because of its high weight capacity, low discharge temperature, and volumetric density. Recycling the dehydride material has however precluded AlH{sub 3} from being implemented due to the large pressures required (>10{sup 5} bar H{sub 2} at 25 C) and the thermodynamic expense of chemical synthesis. A reversible cycle to form alane electrochemically using NaAlH{sub 4} in THF been successfully demonstrated. Alane is isolated as the triethylamine (TEA) adduct and converted to unsolvated alane by heating under vacuum. To complete the cycle, the starting alanate can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride (NaH) This novel reversible cycle opens the door for alane to fuel the hydrogen economy.
Date: January 9, 2009
Creator: Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B & Joshua Gray, J
Partner: UNT Libraries Government Documents Department