The Catalytic Conversion of C1-Cn Hydrocarbons to Olefins and Hydrogen: Microwave-Assisted C-C and C-H Bond Activation

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• 作者：Dennis D. Tanner ; Pramod Kandanarachchi ; Qizhu Ding ; Huawu Shao ; Despina Vizitiu ; and James A. Franz
• 刊名：Energy & Fuels
• 出版年：2001
• 出版时间：January 2001
• 年：2001
• 卷：15
• 期：1
• 页码：197 - 204
• 全文大小：90K
• 年卷期：v.15,no.1(January 2001)
• ISSN：1520-5029

文摘

The gas-phase, carbon-catalyzed, microwave-promoted conversion of methane to ethylene,ethane, acetylene, and hydrogen is reported. A selection of C₁-C₄ hydrocarbons, hexadecane,and a cyclic hydrocarbon, cyclodecane, were also subjected to microwave conversion, resultingprimarily in -olefins, ethylene, and hydrogen. For methane conversion, the products arereminiscent of those found in methane pyrolysis. Microwave-induced cleavage of the liquidhydrocarbons provides conditions for the stabilization, by rapid thermal quenching in ambient-temperature liquid reagent, of products such as terminal olefins that would be labile underconventional (thermal bath) pyrolysis reaction conditions. The reactions of long chain acyclicand cyclic hydrocarbons involve high temperatures in the region of the spark leading to a cascadeof unimolecular scission reactions from initially formed biradicals from cycloalkanes or radicalpairs from linear alkanes, largely to the exclusion of intermolecular radical-radical and radical-molecule reactions. The observed products are discussed in terms of the thermochemistry anddynamics of high-temperature unimolecular biradical and radical decomposition reactions, andmechanisms involving reactive surface metal sites. The reaction rates of alkanes were found toincrease with the molecular weight of the reactants. Mechanistic pathways consistent with theseresults are discussed.