On the mechanism of hydrogenolysis of linear hydrocarbons and its relationship to the Fischer-Tropsch reaction

The products from the reactions of n-octane and 1-octene with H/sub 2/ at low conversion over silica-supported Ni, Ru, and Co catalysts have been examined. In contrast to all previous studies, the ..cap alpha..-olefin was included with the assumption that it would selectively afford an n-alkyl species. The hydrogenolysis of 1-octene or n-octane over Ni at 230/sup 0/ C produced n-alkanes exclusively. Two models of linear alkane hydrogenolysis have been proposed. The key feature of these models is the methylene deinsertion reaction, which represents a new mechanism for the catalytic cleavage of C-C bonds. The two mechanisms readily account for and are consistent with the experimentally observed distributions and suggest that the two schemes are plausible alternatives to currently accepted mechanisms.