Effect of CO2/CO addition in dehydroaromatization of methane on zeolite-supported Mo and Re catalysts towards hydrogen, benzene and naphthalene

High activity and high formation selectivity for aromatics in the dehydrocondensation reaction of methane were realized only on selected catalysts. The requisites of a metal and a zeolite support as the selected catalyst were described. However, the catalytic activity steadily declined even on the selected catalysts with time on stream because of coke accumulation. A stable catalytic activity was obtained when CO2 or CO was added into methane feed due to effective removal of coke from the catalyst surface by CO or CO2. The route from methane to aromatics and the formation process of active phase of catalyst were discussed.