Effect of hierarchical crystal structures on the properties of cobalt catalysts for Fischer–Tropsch synthesis

• Mesoporous zeolites as FT supports were synthesized using double-template method.
• The catalyst with bimodal crystal structure showed higher C5–18 selectivity.
• Higher C5–12 selectivity over Co/ZSM-5 catalyst and higher C12–18 selectivity over Co/SBA-15 catalyst were observed.
• Co loaded on hierarchical crystalline zeolite showed the lowest deactivated rate.

Mesoporous ZSM-5 was synthesized using double-template method and its application in Fischer–Tropsch synthesis (FTS) was studied. By comparison, ZSM-5 and SBA-15 were also prepared. The results demonstrated that the catalysts with bimodal structure and moderate acidity showed higher C5–18 selectivity with relatively lower CH4 selectivity, while higher C5–12 selectivity over Co/ZSM-5 catalyst and higher C12–18 selectivity over Co/SBA-15 catalyst were observed, respectively. Cobalt loaded on crystalline mesoporous ZSM-5 showed the lowest deactivated rate, which suggested that such bimodal structure was favor to the stabilization of cobalt particles. As a result of lower hydrothermal stability of mesopority, Co/SBA-15 catalyst had the fastest deactivation.