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A. S. Berenblyum R. S. Shamsiev T. A. Podoplelova V. Ya. Danyushevsky 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(8):1199-1203
The activity and selectivity of palladium, copper, platinum, and nickel catalysts in the decarbonylation of stearic acid into hydrocarbons were studied at a 14 atm hydrogen pressure and temperatures of 300-350°C. If ??-alumina was used as a carrier, the catalysts formed the series Pd > Cu > Pt > Ni according to desired product yields. Quantum-chemical simulation was performed to show that the free energy of activation increased in the same series. The same metals deposited on mixed tungsten and zirconium oxides catalyzed decarbonylation with a low yield of C17 hydrocarbons, likely because such a superacidic carrier could catalyse cracking of olefins or their oligomers formed. 相似文献
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A.S. Berenblyum A.G. Knizhnik S.L. Mund I.I. Moiseev 《Journal of organometallic chemistry》1982,234(2):219-235
The interaction of Ph3PPD(OAc)22 with molecular H2 yields a binuclear complex of zero-valent palladium, (Ph3P)2Pd2. This complex interacts reversibly with H2 in CH2Cl2, yielding (Ph3P)2Pd2H2. In argon atmosphere (Ph3P)2Pd2 reacts with [Ph3PPd(OAc)22 to form a binuclear complex of PdI with a metal—metal bond. These data, as well as the results of kinetic studies of the reactions between [Ph3PPd(OAc)22 and H2, are in agreement with an autocatalytic mechanism for the process, including catalysis of the reduction of PdII complexes by the Pd0 compounds. It has been established that the synthesized compound of PdII, PdI and Pd0 with the ratio P/Pd?1, are inactive in the hydrogenation of unsaturated compounds. The catalytically active complex (PPh)2Pd5 is formed when palladium acetate reacts with (Ph3P)2Pd2 in the presence of H2. The same compound is formed when a solution of (Ph3P)2Pd2 is treated with a mixture of H2 and O2 (or H2O2 in an atmosphere of H2). (PPh)2Pd5 is an effective catalyst for the hydrogenation of olefins, dienes, acetylenes, aldehydes, organic peroxides, quinones, O2, Schiff bases, and nitro, nitroso, and azo compounds. 相似文献
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A. S. Berenblyum Hussein Ali Al-Wadhaf E. A. Katsman V. R. Flid 《Kinetics and Catalysis》2011,52(2):296-304
The kinetics of the reduction of Pd(II) compounds by dihydrogen on the surface of a carbon support has been investigated for
palladium acetate as an example. A kinetic model has been constructed for this reaction. An autocatalytic mechanism is suggested,
in which the key role is played by Pd(0) compounds and their hydrides. The reaction occurring on the support surface is compared
with the same reaction in solutions of palladium phosphine acetate complexes, where a similar mechanism is observed. One of
the most important features of the surface reaction is the relatively slow reduction of the Pd(I) compounds to Pd(0). This
makes it possible to obtain materials with a high Pd(I) content of 5% and above. 相似文献