Improving thermal diffusivity of supported Fe-based Fischer–Tropsch catalysts to enhance long-chain hydrocarbon production

Abstract

Hydrocarbon fuels and other high-valued chemicals traditionally obtained from petroleum can be produced via the green and sustainable Fischer–Tropsch synthesis (FTS). However, the FTS reaction is highly exothermic which is suggested to have adverse effects on the overall performance of the catalysts. In this work, the effects of improved thermal diffusivity of the catalysts on FTS performance were investigated using pulverized aluminum (Al) mixed with SiO₂ supported Fe catalysts. The Al content was varied and subsequent influence on the catalyst and product distribution was highlighted. By design, it was observed that the addition of Al barely influenced the intrinsic physicochemical properties of the basic Fe catalyst. However, it increases the thermal diffusivity of the catalyst which corresponded to an increased selectivity for long-chain hydrocarbons. These results directly clarify the influence of thermal diffusivity on catalytic activity and reveal a plausible path to efficiently reduce its impact on the FTS reaction.