Studying the Aluminum–Palladium Catalysts for Selective Acetylene Hydrogenation into Ethylene Prepared by Surface Self–Propagating Thermal Synthesis
O. O. MIRONENKO1, N. B. SHITOVA1, N. S. SMIRNOVA1, D. I. KOCHUBEY2, L. S. KIBIS2, R. V. GULYAEV2, A. I. BORONIN2 and P. G. TSYRUL'NIKOV1
1Institute of Hydrocarbons Processing, Siberian Branch of the Russian Academy of Sciences, Ul. Neftezаvodskаya 54, Omsk 644040 (Russia)
E-mail: olesyashsh@rambler.ru
2Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences, Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia)
Keywords: self-propagating surface thermal synthesis, liquid-phase hydrogenation of acetylene, EXAFS, XPES, Pd/Al2O3
Pages: 71–81
Abstract
Studies concerning supported aluminum-palladium catalysts obtained via surface self-propagating thermal synthesis (SSTS) for the selective liquid-phase hydrogenation of acetylene into ethylene in the presence of CO were performed. According to the results of catalytic testing, in the case of running the reaction at 60 °C the SSTS catalysts are inferior to the samples prepared in a conventional manner. At a temperature of 90 °C, the catalyst prepared via SSTS with using citric acid as a fuel additive is almost similar to the sample prepared via traditional method, in the catalytic properties thereof. According to the results obtained by EXAFS and XPS, the original SSTS catalysts contain palladium in oxidized and reduced forms, whose ratio depends on the nature and content of the fuel additive. It has been found that palladium oxide in SSTS catalysts can be quickly reduced under the reaction conditions to produce zero-valent Pd, which is indicated by the results of studying the SSTS catalysts before and after the reaction by means of EXAFS.
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