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Catalyst and Feedstock Effects in the Thermochemical Conversion of Biomass to Liquid Transportation Fuels

Description: The thermochemical conversion of biomass feedstocks to liquid transportation fuels can be accomplished by three processes, namely gasification, high-pressure liquefaction, and pyrolysis. In this study, the pyrolysis option is selected which is followed by the catalytic upgrading of pyrolysis vapors to aromatic and olefinic hydrocarbons (PYROCAT process). The aromatics constitute a high-octane gasoline blend, while the olefins can be utilized as feedstocks for various chemicals. The PYROCAT proc… more
Date: May 1992
Creator: Rejai, B.; Agblevor, F. A.; Evans, R. J. & Wang, D.
Partner: UNT Libraries Government Documents Department
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Gaseous phase coal surface modification

Description: In this report, we present an improved, feasible and potentially cost effective method of cleaning and beneficiating ultrafine coal. Increased mechanization of mining methods and the need towards depyritization, and demineralization have led to an increase in the quantity of coal fines generated in recent times. For example, the amount of {minus}100 mesh coal occurring in coal preparation plant feeds now typically varies from 5 to 25% of the total feed. Environmental constraints coupled with th… more
Date: May 7, 1992
Creator: Okoh, J.M.; Pinion, J. & Thiensatit, S.
Partner: UNT Libraries Government Documents Department
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Sulfur-isotope separation by distillation

Description: Sulfur-isotope separation by low-temperature distillation of hydrogen sulfide was studied in an 8-m, 25-mm diameter distillation column. Column temperature was controlled by a propane-propylene heat pipe. Column packing HETP was measured using nitric oxide in the column. The column was operated at pressures from 45 to 125 kPa. The relative volatility of S-32 vs. S-34 varied from 1.0008 to 1.0014.
Date: January 1, 1982
Creator: Mills, T.R.
Partner: UNT Libraries Government Documents Department
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Stereospecificity and physiology of co-oxidative production of chemicals by methanotrophic bacteria. [Methane monooxygenase:a2]

Description: Methanotrophic bacteria can use methane as a sole source of carbon and energy. The enzyme responsible for the oxidation of methane in these organisms, methane monooxygenase, is also able to biotransform a number of substrates into industrially important chemicals. One such example is the oxidation of propylene to propylene oxide. Several strains of mesophilic and thermophilic methanotrophs have been tested for their ability to produce propylene oxide with formate, methanol, and methane as the c… more
Date: January 1, 1991
Creator: Kelley, R. L.; Hoefer, D. E.; Conrad, J. R.; Srivastava, V. J. & Akin, C.
Partner: UNT Libraries Government Documents Department
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Polyketones and polysulfones for conservation in the ethylene polymer industry. Progress report No. 6, July-September 1979

Description: The characterization study on ethylene-CO (Et-CO) copolymers was concluded. The copolymers were prepared at various levels of CO composition, and with several methods loss of catalysis, including free-radical, metallic, and /sup 60/Co irradiation. Et-CO copolymers exhibit crystallinity related to the alternating polyketone structure which increasees logarithmically with CO content over the range 28% to 49% CO. The melting point increases in essentially the same manner as crystallinity. The stru… more
Date: January 1, 1980
Creator: Steinberg, M.; Johnson, R.; Elling, D.; Cordes, W. & Goodman, D.
Partner: UNT Libraries Government Documents Department
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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 s… more
Date: January 31, 2007
Creator: Waslylenko, Walter & Frei, Heinz
Partner: UNT Libraries Government Documents Department
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DOE Award No. DE-FC36-03GO13108 Novel Non-Precious Metal Catalysts for PEMFC: Catalyst Selection Through Molecular Modeling and Durability Studies Final Report (September 2003 – October 2008)

Description: The objective of this project is to develop novel non-precious metal electrocatalysts for oxygen reduction reaction (ORR), and demonstrate the potential of the catalysts to perform at least as good as conventional Pt catalysts currently in use in polymer electrolyte membrane fuel cell (PEMFC) with a cost at least 50 % less than a target of 0.2 g (Pt loading)/peak kW and with durability > 2,000 h operation with less than 10 % power degradation. A novel nitrogen-modified carbon-based catalyst was… more
Date: March 3, 2009
Creator: Popov, Branko N.
Partner: UNT Libraries Government Documents Department
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TRITIUM EFFECTS ON DYNAMIC MECHANICAL PROPERTIES OF POLYMERIC MATERIALS

Description: Dynamic mechanical analysis has been used to characterize the effects of tritium gas (initially 1 atm. pressure, ambient temperature) exposure over times up to 2.3 years on several thermoplastics-ultrahigh molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE), and Vespel{reg_sign} polyimide, and on several formulations of elastomers based on ethylene propylene diene monomer (EPDM). Tritium exposure stiffened the elastic modulus of UHMW-PE up to about 1 year and then softened i… more
Date: November 12, 2008
Creator: Clark, E
Partner: UNT Libraries Government Documents Department
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DOE Award No. DE-FC36-03GO13108 Novel Non-Precious Metal Catalysts for PEMFC: Catalyst Selection Through Molecular Modeling and Durability Studies Final Report (September 2003 – October 2008)

Description: The objective of this project is to develop novel non-precious metal electrocatalysts for oxygen reduction reaction (ORR), and demonstrate the potential of the catalysts to perform at least as good as conventional Pt catalysts currently in use in polymer electrolyte membrane fuel cell (PEMFC) with a cost at least 50 % less than a target of 0.2 g (Pt loading)/peak kW and with durability > 2,000 h operation with less than 10 % power degradation. A novel nitrogen-modified carbon-based catalyst was… more
Date: February 20, 2009
Creator: Popov, Branko N.
Partner: UNT Libraries Government Documents Department
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Removal of Iodide From Groundwater Using Silver Chloride-White Paper

Description: Releases from the F and H Area Seepage Basins on the Savannah River Site (SRS) have caused groundwater plumes that contain a variety of contaminants. These plumes are releasing contaminants into Fourmile Branch, which is a small tributary of the Savannah River. The metallic contaminant releases to the branch are being controlled by base injection. The base injection targets cationic contaminants and was not intended to reduce the concentration of I-129 in groundwater. SRS and the regulatory age… more
Date: November 26, 2008
Creator: Denham, M.; Bach, M. & Millings, M.
Partner: UNT Libraries Government Documents Department
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Bench-Scale Co-Oxidative Production of Propylene Oxide by Methanotrophs

Description: The feasibility of the co-oxidative production of value-added chemicals using methanotrophs has been investigated by the authors. Several of these co-oxidative products have been evaluated for stereo- or regiospecific properties. Propylene oxide (1,2-epoxypropane) is one of the products that has been selected for further evaluation. This paper describes the first steps toward bench-scale production of propylene oxide. Propylene oxide has been produced stereospecifically (60% R-form, 40% S-form)… more
Date: January 1, 1990
Creator: Hill, A. H.; Kelley, R. L.; Srivastava, V. J.; Akin, C .A; Hayes, T. D. & Frank, J. R.
Partner: UNT Libraries Government Documents Department
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Energy minimization of separation processes using conventional/membrane hybrid systems

Description: The purpose of this study was to identify the general principles governing the choice of hybrid separation systems over straight membrane or straight nonmembrane systems and to do so by examining practical applications (process design and economics). Our focus was to examine the energy consumption characteristics and overall cost factors of the membrane and nonmembrane technologies that cause hybrid systems to be preferred over nonhybrid systems. We evaluated four cases studies, chosen on the b… more
Date: September 28, 1990
Creator: Gottschlich, D.E. & Roberts, D.L. (SRI International, Menlo Park, CA (USA))
Partner: UNT Libraries Government Documents Department
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Utilization of shale oil as a feedstock for steam pyrolysis and petrochemical intermediate production. Quarterly technical progress report, June-August 1978

Description: During the past quarter, 5 runs were made on a number of hydrotreated samples including a mildly hydrotreated simulated in-situ (1.35% N) and two moderately hydrotreated Tosco II (0.82% N and 1.55% N) distillates. The results are, in general, consistent with previous results which indicated an increase in olefins yield as the severity of hydrogenation increased. The olefins yields for the simulated in-situ oil were greater than those for the Tosco II oil for oil hydrogenated to comparable sever… more
Date: September 5, 1978
Creator: Dickson, P. F. & Yesavage, V. F.
Partner: UNT Libraries Government Documents Department
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(Studies of supported hydrodesulfurization catalysis)

Description: Research progress to be reviewed here will be in three areas. First, correlation of the distribution of molybdenum oxidation states in reduced Mo/Al{sub 2}O{sub 3} catalysts with benzene hydrogenation activity. Second, the use of factor analysis curve-fitting to determine the distribution of molybdenum oxidation states in reduced Mo/TiO{sub 2} catalysts. Third, quantitative Raman and ESCA characterization of W/TiO{sub 2} catalysts.
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department
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Study of practical cycles for geothermal power plants. Interim report, June 15, 1975-March 31, 1976

Description: The preliminary analysis is described in a study of practical cycles for geothermal power plants. The analysis is based on three different brines whose temperatures and composition span the range that is of practical interest for power generation. Only two kinds of cycles were considered in the analysis - the steam turbine cycle and the binary cycle, in which energy from the geothermal fluid is transferred to a secondary working fluid in a closed Rankine cycle. The performance of several condid… more
Date: April 1, 1976
Creator: Eskesen, J.H.
Partner: UNT Libraries Government Documents Department
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Polyketones and polysulfones for conservation in the ethylene polymer industry. Progress report No. 5, April-June 1979

Description: Reaction kinetic studies were continued on the /sup 60/Co gamma-induced polymerization of ethylene-SO/sub 2/ (Et-SO/sub 2/) mixtures. A peak in reactivity, as measured by an overall G-value of 8.4 x 10/sup 4/ molecules/100 eV, was found at 1.9 mole % SO/sub 2/ for gas-phase mixtures containing up to 6.7 mole % SO/sub 2/ and over a pressure range of 22.3 to 56.1 atm. Overall rates and G-values were obtained for liquid-phase SO/sub 2/ saturated with ethylene at up to 58.2 atm total pressure. A ma… more
Date: August 1, 1979
Partner: UNT Libraries Government Documents Department
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First results from electron-photon damage equivalence studies on a generic ethylene-propylene rubber

Description: As part of a simulator adequacy assessment program, the relative effectiveness of electrons and photons to produce damage in a generic ethylene propylene rubber (EPR) has been investigated. The investigation was limited in extent in that a single EPR material, in three thickness, was exposed to Cobalt-60 photons and three electron beam energies. Basing material damage on changes in the EPR mechanical properties elongation and tensile strength, we observed that EPR damage was a smoothly varying … more
Date: April 1, 1986
Creator: Buckalew, W.H.
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 31, 1979. [Methanol from synthesis gas from coal gasification]

Description: An attractive route for producing ethylene and propylene from coal is to gasify the coal to produce synthesis gas, convert the synthesis gas to methanol, and then convert methanol to the olefins. During this report period the reactions of methanol over chabazite ion exchanged with rare earth chlorides have been studied at reciprocal liquid hourly space velocities of 1.5 to 15, at temperatures of 259, 271, 304, 352, and 427/sup 0/C, and at pressure 2.7 atm. At 259 and 271/sup 0/C the principle p… more
Date: July 31, 1979
Creator: Anthony, R. G.
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.
Partner: UNT Libraries Government Documents Department
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Cask systems development program seal technology

Description: General design or test performance requirements for radioactive materials (RAM) packages are specified in Title 10 of the US Code of Federal Regulations Part 71 (10 CFR 71). Seals that provide the containment system interface between the packaging body and the closure must function in both high- and low-temperature environments under dynamic and static conditions. Experiments were performed to characterize the performance of several seal materials at low temperatures. Helium leak tests on face … more
Date: January 1, 1991
Creator: Madsen, M.M.; Edwards, K.R. & Humphreys, D.L.
Partner: UNT Libraries Government Documents Department
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Catalytic conversion of oxygenated compounds to low molecular weight olefins. Annual report for January 1--December 31, 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, propylene, and propane with carbon yields of 70 to 90% at reaction temperatures of 360 to 450/sup 0/C and pressures from 1 to 18 atmospheres. Carbon disulfide in the feed at concentrations less than 2000 ppm increases the operating time between regenerations from four hour… more
Date: January 1979
Creator: Anthony, Rayford G.
Partner: UNT Libraries Government Documents Department
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Carbon isotope separation by absorptive distillation. [77. 4 to 114. 3/sup 0/K]

Description: The feasibility of separating carbon isotopes by absorptive distillation has been studied for CO absorption by cryogenic solvents. Phase equilibrium, isotopic separation, and mass transfer data were taken between 77.4 and 114.3 K for the following solvents: propane, propylene, 1:1 propane-propylene, 1-butene, isobutane and nitrogen. Carbon monoxide solubility followed Henry's Law, with a maximum experimental solubility of 6.5 mole percent. Isotopic separation between CO in the gas and liquid ph… more
Date: January 1, 1979
Creator: Mills, T.R.
Partner: UNT Libraries Government Documents Department
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Oxo chemistry in supercritical carbon dioxide

Description: We report an investigation of the cobalt carbonyl-catalyzed oxo process in supercritical CO{sub 2} using in situ high pressure NMR spectroscopy. The use of supercritical CO{sub 2} as the solvent medium eliminates gas-liquid mixing problems. The effect of supercritical CO{sub 2} on the oxo reaction was determined by comparing the linear to branched aldehyde yield and rate and other equilibrium processes involved in the catalytic cycle with measured values in conventional liquid solvents.
Date: January 1, 1991
Creator: Krause, T.R.; Rathke, J.W. & Klingler, R.J.
Partner: UNT Libraries Government Documents Department
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Evaluation of seals for a geothermal logging tool

Description: The seal efficiency and environmental resistance of various elastomeric o-rings and a metallic joint that were immersed in geothermal brine or water at elevated temperatures and pressures were determined. A leakproof seal was maintained with a stainless steel Conoseal-joint for 100 hours in water and 24 hours in geothermal brine at 275/sup 0/C and 34.5 MPa (5000 psi). Only very small quantities of moisture penetrated o-ring seals made from Kalrez, a perfluoroelastomer, ethylene/propylene rubber… more
Date: January 1, 1978
Creator: Arnold Jr., C.; Coquat, J. A. & Baker, L. E.
Partner: UNT Libraries Government Documents Department
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