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Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly report, April 1-June 30, 1980. [Pt/Pd]

Description: Phase II of the contract, which involved catalyst preparation and evaluation, was nearly completed this quarter. Phase III, which calls for the design and construction of a fuel processor, was started. During the quarter, four types of tests were run on the small scale catalyst screening unit. The operating line for coke-free operations was found to be approximately between 0.41 to 0.44 O/sub 2//C level. Screening at lower O/sub 2//C levels led to problems with plugging. In other tests, increas… more
Date: July 1, 1980
Creator: Yarrington, R M; Feins, I R & Hwang, H S
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel nanodispersed coal liquefaction catalysts: Molecular design via microemulsion-based synthesis

Description: The objective of this project is to pursue the development of highly dispersed and inexpensive catalysts for improved coal solubilization and upgrading of coal liquids. A novel study of the synthesis of liquefaction catalysts of nanometer size will be carried out. It is based on the molecular design of reverse micelles (microemulsions). These surfactant-stabilized, metal-bearing microdrops offer unique opportunities for synthesizing very small particles by providing a cage-like effect that limi… more
Date: July 1, 1991
Creator: Osseo-Asare, K. & Radovic, L.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Combined shift and methanation in a fluidized-bed reactor. Quarterly progress report, 1 April-30 June 1980

Description: Only one bench-scale reactor test was completed. The Harshaw Ni/Cu/Mo and UCI (composition undisclosed) catalysts were evaluated over a 12-day period at 800 F and a feed gas H/sub 2//CO ratio of 2/1. Initial conversions with both catalysts were about 33 percent; and the activities of both samples declined steadily during the test, with final conversion values in the 15 to 20 percent range. During this test, problems were experienced with water carryover into the Drierite traps, necessitating so… more
Date: July 1, 1980
Creator: Streeter, R C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of improved iron Fischer-Tropsch catalysts

Description: The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.
Date: July 19, 1991
Creator: Bukur, D.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of fluoride, chloride, bromide, and thiocynate on potentiometric titrations of iron(II)-tin(II) mixtures with cerium(IV)

Description: A two-step curve is expected in the potentiometric titration of Fe(II)-Sn(II) mixtures with Ce(IV) in H/sub 2/SO/sub 4/. Each end point should indicate the respective oxidation of Sn(II) and Fe(II). However, experimentally only one end point was found; it corresponded to the total oxidation of Sn(II) and Fe(II). When this oxidation-reduction reaction was carried out in the presence of Cl/sup -/, the theoretical behavior was observed. The present study was done to ascertain if monovalent anions … more
Date: July 31, 1980
Creator: Kwok, Y.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Exploratory research on solvent refined coal liquefaction. Quarterly technical progress report, July 1, 1979-September 30, 1979

Description: This report summarizes the progress of the Exploratory Research on Solvent Refined Coal Liquefaction project by The Pittsburgh and Midway Coal Mining Co.'s Merriam Laboratory for the period July 1, 1979 through September 30, 1979. In a series of experiments with varying feed gas composition, high levels (20 to 40 mol %) of carbon monoxide resulted in a general degradation of operability and reduced oil yields from Powhatan coal (Pittsburgh Seam). Addition of finely divided pyrite to the reactiv… more
Date: July 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Probe molecule studies: Active species in alcohol synthesis

Description: The goal of this research is to develop a better understanding of the mechanisms of formation of alcohols and other oxygenates from syngas over supported catalysts. Different probe molecules are planned to add in situ during the reaction to help delineate reaction path ways and identify reaction intermediate species. The key of our study is to investigate how the species generated by these probe molecules interact with surface species present during oxygenate formation. CO hydrogenation reactio… more
Date: July 1, 1991
Creator: Blackmond, D.G. & Wender, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Adsorption of energy in photocatalytic reactors

Description: The dissociation of water to hydrogen and oxygen requires energy ..delta..G/sub 298/ = 228 kJ/mole. By irradiating a semiconductor with light of energy greater than this amount, one may produce electrons in the excited state and electron vacancies at the surface that can perform the photochemical reduction (2H/sup +/ + 2e/sup -/ ..-->.. 2H ..-->.. H/sub 2/) and oxidation (20H/sup -/ + 2/sup +/ ..-->.. H/sub 2/O/sub 2/ ..-->.. H/sub 2/O + (1/2)O/sub 2/). There are several semiconductors, SrTiO/s… more
Date: July 1, 1985
Creator: Somorjai, G.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An innovative catalyst system for slurry-phase Fischer-Tropsch synthesis: Cobalt plus a water-gas-shift catalyst

Description: The feasibility of using a mechanical mixture of a Co/MgO/SiO{sub 2} Fischer-Tropsch catalyst and a Cu-ZnO/Al{sub 2}O{sub 3} water-gas-shift (WGS) catalyst for hydrocarbon synthesis in a slurry reactor has been established. Such a mixture can combine the superior product distribution from cobalt with the high activity for the WGS reaction characteristic of iron. Weight ratios of Co/MgO/SiO{sub 2} to Cu-ZnO/Al{sub 2}O{sub 3} of 0.27 and 0.51 for the two catalysts were studied at 240{degrees}C, 0… more
Date: July 1, 1991
Creator: Satterfield, C. N.; Yates, I. C. & Chanenchuk, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Kinetics and dynamics of oxidation reactions involving an adsorbed CO species on bulk and supported platinum and copper-oxide

Description: The proposed research is an integrated experimental and modeling study of oxidation reactions involving CO as a key player -- be it a reactant, adsorbed intermediate, and/or partial oxidation product -- in the catalytic sequence and chemistry. The reaction systems of interest in the project include CO, formaldehyde, and methanol oxidation by O{sub 2} and CO oxidation by NO, on both Pt and copper oxide catalysts. These reactions are of importance in automobile exhaust catalysis. There is a pauci… more
Date: July 1, 1991
Creator: Harold, M.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Catalytic gasification studies in a pressurized fluid-bed unit

Description: The purpose of the project is to evaluate the technical and economic feasibility of producing specific gas products via the catalytic gasification of biomass. This report presents the results of research conducted from October 1980 to November 1982. In the laboratory scale studis, active catalysts were developed for generation of synthesis gases from wood by steam gasification. A trimetallic catalyst, Ni-Co-Mo on silica-alumina doped with 2 wt % Na, was found to retain activity indefinitely for… more
Date: July 1, 1983
Creator: Mudge, L.K.; Baker, E.G.; Mitchell, D.H.; Robertus, R.J. & Brown, M.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalytic conversion of oxygenated compounds to low molecular weight olefins. Progress report, January 1--July 15, 1978

Description: The conversion of methanol or synthesis gas is an attractive route for producing ethylene and propylene from coal. Utilizing a chabazite ion exchanged with ammonium and rare earth chlorides, methanol is converted to ethylene and propylene with carbon yields of 70 to 90% at reaction temperatures of 375 to 425/sup 0/C and pressures to 100 psi. Carbon disulfide in the feed at concentrations less than 200 ppM increases the operating time between regenerations from four hours to twenty hours. At car… more
Date: July 1978
Creator: Anthony, Rayford G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Methanation reaction on ruthenium thin films: a mechanistic investigation.

Description: The kinetics of the methanation reaction were measured on thin ruthenium films in the temperature range 548 to 623K. The pressures of the reactant gases were varied over the ranges 1.5 to 1500 ..mu..m for CO and 300 to 75000 ..mu..m for H/sub 2/ to yield kinetic orders for each gas. The CO kinetic order varied from +1 at low pressures to -2 at high pressures. As the H/sub 2/ pressure was increased its kinetic order varied from +2 to -1. Both of these order plots had unusually sharp maxima. The … more
Date: July 1, 1979
Creator: Slaughter, M. D.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Bimetallic promotion of cooperative hydrogen transfer and heteroatom removal in coal liquefaction

Description: The ultimate objective of this research is to uncover new catalytic processes for the liquefaction of coal and for upgrading coal-derived fuels by removing undesirable organosulfur, organonitrogen and organooxygen constituents. Basic to both the liquefaction of coal and the purification of coal liquids is the transfer of hydrogen from such sources as dihydrogen, metal hydrides or partially reduced aromatic hydrocarbons to the extensive aromatic rings in coal itself or to aromatic sulfides, amin… more
Date: July 1, 1991
Creator: Eisch, J.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalytic oxidation of tritium in air at ambient temperature

Description: Tritium/air oxidation kinetic data are derived from ambient-temperature measurements carried out with three precious-metal catalysts. Each catalyst consists of a high-surface-area substrate in pelletized form, onto which precious metal has been dispersed. The metal/substrate combinations investigated are platinum/alumina, palladium/kaolin, and palladium/zeolite. Electron-microprobe scans reveal that the dispersed metal is deposited in each case near the outer surface of the pellet, with metal c… more
Date: July 1, 1979
Creator: Sherwood, A.E.; Monahan, B.G.; McWilliams, R.A.; Uribe, F.S. & Griffith, C.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Zeolite catalysis: technology

Description: Zeolites have been used as catalysts in industry since the early nineteen sixties. The great majority of commercial applications employ one of three zeolite types: zeolite Y; Mordenite; ZSM-5. By far the largest use of zeolites is in catalytic cracking, and to a lesser extent in hydrocracking. This paper reviews the rapid development of zeolite catalysis and its application in industries such as: the production of gasoline by catalytic cracking of petroleum; isomerization of C/sub 5/ and C/sub … more
Date: July 1, 1980
Creator: Heinemann, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CO + H/sub 2/ reaction over nitrogen-modified iron catalysts. Quarterly technical progress report, January 1-March 31, 1984

Description: We have found that the nitride catalysts lose substantial amounts of nitrogen during the initial minutes of Fischer-Tropsch synthesis. In order to further study the stability of these catalysts, we have concentrated on the decomposition of the nitride in hydrogen. In addition, we have prepared a range of epsilon-Fe/sub x/N (2 < x < 3) phases. The Moessbauer parameters from these phases will aid in the identification and fitting of the transient epsilon phases formed during the carburization of … more
Date: July 1, 1984
Creator: Delgass, W.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalytic coal liquefaction. Final technical report, June 1, 1981-May 31, 1984

Description: Molybdenum catalysts (both supported and unsupported) have been examined in various stages of preparation and use with respect to BET surface area and low temperature oxygen chemisorption. The results are detailed. X-ray diffraction has been used to characterize ammonium molybdate - after calcination, heated in tetralin under nitrogen and after use in an autoclave. Metal salts have been tested for catalytic effects by heating a tetralin-coal mixture (without hydrogen) at a loading of 1% of the … more
Date: July 1, 1984
Creator: Weller, S. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sequential low-temperature depolymerization and liquefaction of US coals

Description: The Elkhorn (Kentucky) coal sample, referred below as EH(KY) coal, had the following ultimate analysis (MAF basis), in wt %: C, 85--36; H, 5.69; N, 1.75; Cl, 0.18; S, 0.72; 0 (diff) 6.30. H/C atomic ratio - 0.80; ash content (dry basis), 6.60 %. The sample showed a calorific value of 14,324 BTU/ib (dry basis). As indicated by its ultimate analysis and calorific value, the EH(Ky) coal was of somewhat higher rank as compared with the previously studied HVB coal sample from Burning Star (Illinois … more
Date: July 1, 1987
Creator: Shabtai, J. S. & Wiser, W. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalysis by platinum single crystal surfaces: low pressure hydrocarbon reactions and the effects of introducing strongly bound oxygen at the surface

Description: The dehydrogenation of cyclohexene and cyclohexane, and the hydrogenation of cyclohexene were studied on the clean and preoxidized surfaces of three platinum single crystals: a Pt(111), a stepped Pt(S) - (6(111) x (100)) and a kinked Pt(S) - (7(111) x (310)). The choice of reaction conditions is discussed with respect to detection limits and the variation of the catalyst reactivity with reagent pressures and catalyst temperature; the reactions were carried out using flow conditions at low press… more
Date: July 1, 1978
Creator: Smith, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Bench-scale co-processing

Description: The objective of this contract is to extend and optimize UOP's single-stage slurry-catalyzed co-processing scheme. Particular emphasis is given to defining and improving Mo catalyst utilization and cost, evaluating alternative and disposable slurry-catalyst systems, and improving catalyst recycle and recovery techniques. During the previous quarter, a catalyst concentration study was completed. The study showed that the highest nondistillable conversions and liquid yields were achieved using li… more
Date: July 9, 1990
Creator: Nafis, D.A.; Gatsis, J.G.; Lea, C. & Miller, M.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, April 1, 1992--June 30, 1992

Description: A rate equation for carbon monoxide consumption showing first order in CO and 0.5 order in hydrogen indicates the rate controlling step involves dissociated hydrogen. The inhibition of the rate with carbon dioxide is also shown. Examination of the hydrocarbon distributions indicates a see-saw effect with the C{sub 4}s representing the fulcrum and methane and C{sub 5}{sup +} the end points. The shift in the distributions tends to be towards the C{sub 5}{sup +} for high pressures and long residen… more
Date: July 27, 1992
Creator: Anthony, R. G. & Akgerman, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Kinetics and dynamics of oxidation reactions involving an adsorbed CO species on bulk and supported platinum and copper-oxide. First year annual report, January 1, 1991--December 31, 1991

Description: The proposed research is an integrated experimental and modeling study of oxidation reactions involving CO as a key player -- be it a reactant, adsorbed intermediate, and/or partial oxidation product -- in the catalytic sequence and chemistry. The reaction systems of interest in the project include CO, formaldehyde, and methanol oxidation by O{sub 2} and CO oxidation by NO, on both Pt and copper oxide catalysts. These reactions are of importance in automobile exhaust catalysis. There is a pauci… more
Date: July 1, 1991
Creator: Harold, M. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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