Insight into the Influence of Carbon on Core-Shell Structured Co-Z@TiO₂ Catalysts for Fischer-Tropsch Synthesis

ZIF-67 derived cobalt-based catalysts have potential for Fischer-Tropsch synthesis (FTS). In this work, core-shell structured Co-Z@TiO₂ catalysts with different graphitization degrees and carbon contents were handily prepared by adjusting the calcination process, using the ZIF-67 encapsulated by amorphous TiO₂ as the precursor. By the protection effect of the residual carbon, the aggregation of cobalt species was suppressed. The dispersion and reducibility of the catalyst can be regulated by manipulating the type and amount of residual carbon. The Co-Z@TiO₂ catalyst with proper carbon content exhibited high CO conversion (36.9%), C₅₊ selectivity (80.4%), and especially gasoline range hydrocarbons (49.3%). The catalyst also showed good stability during a 110 h reaction.