Hydrogenolysis of n-eicosane over Ru-based catalysts in a continuous flow reactor

Abstract

The hydrogenolysis of n-eicosane (C20H42) was studied under differential conditions over Ru-based catalysts including Ru/SiO2, Ru/TiO2, and Ru/SBA-15, using a continuous flow reactor that was specially designed for large hydrocarbon reactants that are solids at room temperature. Similar rates and product distributions were obtained for Ru/SiO2 and Ru/SBA-15 at 433 K, with the most abundant products being C1 and C19 hydrocarbons and smaller amounts of C8 to C18 also being produced. The higher yield of C1 and C19 indicates that cleavage of the terminal CC bond is somewhat more facile than an internal CC bond. At 473 K the product distribution shifted to mostly C1 suggesting that, at this temperature, the adsorbed alkyl fragments undergo complete CC bond scission prior to desorbing. The conversion was also found to be inversely proportional to the H2 pressure. Similar results were obtained for Ru/TiO2 except this catalyst was found to be less active than both Ru/SiO2 and Ru/SBA-15.