Type of hydrocarbon activation and nature of active sites of base catalysts in methane oxidative dehydrodimerization

Autor:	O.V. Buyevskaya, A.A. Davydov, S.M. Aliev, V.D. Sokolovskii
Rok vydání:	1989
Předmět:	chemistry.chemical_classification Reaction step Inorganic chemistry Methyl radical General Chemistry Activation energy Heterolysis Catalysis Dissociation (chemistry) Methane chemistry.chemical_compound Hydrocarbon chemistry
Zdroj:	Catalysis Today. 4:293-300
ISSN:	0920-5861
DOI:	10.1016/0920-5861(89)85025-4
Popis:	Methane activation on magnesium-oxide-cased catalysts for methane dehydrodimerization has been studied. As found, the rate of dehydrodimerization changes proportionally with the concentration of base sites on the catalytic surface. The activation of methane results in the formation of the methyl anion, as ascertained by IR-Fourier spectroscopy. The dehydrodimerization rates have been compared with the concentration of one-electron sites and the rate of the CH 4 CD 4 isotope exchange. Based on the data obtained a new mechanism of methane dehydrodimerization has been proposed; at the first reaction step a fast heterolytic dissociation of methane on base sites takes place. The rate-determining step is that of the metal-methyl dissociation leading to the formation of the methyl radical which determines a high activation energy of methane dehydrodimerization on oxide catalysts.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::7256dc18b440cbfb40ee6af875b0c1be https://doi.org/10.1016/0920-5861(89)85025-4 Zobrazit plný text záznamu