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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

Description: This report describes progress on research during the seventh quarter of this contract dealing with applications of coal pretreatment techniques in coal hydroliquefaction. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal conversion utilizing low rank coals and low severity conditions (reaction temperatures generally less than 350 {degrees}C) are the primary focus of the liquefaction experiments, as it is expected that the effect of pretreatment conditions and the attendant reactivity enhancement will be greatest for these coals at these conditions.
Date: January 1, 1990
Creator: Baldwin, R.M. & Miller, R.L.
Partner: UNT Libraries Government Documents Department

Catalytic steam gasification of carbon

Description: Unsupported carbide powders with high specific surface area, namely {alpha}-WC (35 m{sup 2}/g, hexagonal), {beta}-WC{sub 0.61} (100 m{sup 2}/g, cubic face centered) and {beta}-WC{sub 0.5} (15 m{sup 2}/g, hexagonal) have been prepared. The key element in this preparation is the successful removal of surface polymeric carbon by careful gasification to methane by means of dihydrogen. These tungsten carbide powders have been used in catalytic reactions of oxidation of H{sub 2} and hydrogenolysis of alkanes, such as butane, hexane, and neopentane.
Date: December 31, 1990
Creator: Boudart, M.
Partner: UNT Libraries Government Documents Department

(Photoexcited charge pair escape and recombination)

Description: Progress in four research areas on this project are summarized under the following topics: (1) Geminate charge pair recombination in hexane; (2) Fast current measurements resulting from excitation of charge transfer (CT) states; (3) Measurement of the dipole moment of excited states by DC conductivity; and (4) Charge separation at macroscopic interfaces between electron donor and acceptor solids. In a final section, personnel who have contributed to the project during the past budget period are described.
Date: January 1, 1990
Creator: Braun, C.L.
Partner: UNT Libraries Government Documents Department

Transuranic organometallics: The next generation

Description: Neptunium and plutonium metal react cleanly with 3/2 equiv. I{sub 2} in aprotic ligating solvents, L, such as tetrahydrofuran (THF), pyridine (Py), and dimethylsulfoxide (DMSO) to give the triiodide complexes as tetrasolvates, AnI{sub 3}(L){sub 4} (An = Np, L = THF (1)); An = Pu, L = THF (2a), Py (2b), and DMSO (2c). These triiodide complexes are convenient precursors to new transuranic compounds. Reaction of the triiodide complexes 1 and 2a hexane with 3 equiv. of sodium bis(trimethylsilyl)amide give the volatile, solvate-free tris(silylamide) complexes, An(N(SiMe{sub 3}){sub 2}){sub 3} (An = Np, 3; An = Pu, 4). The silylamide complexes 3 and 4 undergo rapid reaction in hexane upon stoichiometric addition of HO-2,6-(t-C{sub 4}H{sub 9}){sub 2}C{sub 6}H{sub 3} to give the aryl oxide complexes An(O-2,6-(t-C{sub 4}H{sub 9}){sub 2}C{sub 6}H{sub 3}){sub 3} (An = Np, 5; An = Pu, 6). Preliminary investigations suggest that the aryl oxide complexes 5 and 6 react with lithium bis(trimethylsilyl)methanide, Li{sup +} CH(SiMe{sub 3}){sub 2}, in hexane to give the homoleptic alkyl complexes An(CH(SiMe{sub 3}){sub 2}){sub 3} (An = Np, 7; An = Pu, 8). The homoleptic silylamide, aryl oxide, and alkyl complexes are the first to be reported for transuranic elements. 17 refs.
Date: January 1, 1990
Creator: Zwick, B.D.; Sattelberger, A.P. & Avens, L.R.
Partner: UNT Libraries Government Documents Department