Foam-structured Fe catalysts for enhanced heat and mass transfer in synthesis of olefins from syngas

Abstract

The Fischer-Tropsch (FT) synthesis, characterized by its highly exothermic and high-throughput nature, traditionally yields a mix of C hydrocarbons and C1 by-products, which adversely affect carbon utilization efficiency. Herein, we design a Fe-foam structured catalyst to selectively produce high-value olefins in FT process. The Na-Zn-Fe/Fe-foam catalysts are prepared through a hydrothermal synthesis method, where the FeCO precursor is formed from Fe-foam, followed by addition of sodium and zinc modifiers. These catalysts achieve a remarkable olefin selectivity of ∼80 % and a space-time yield of ∼0.70 g g h at a CO conversion of 98 %, and further demonstrate outstanding stability. The structured catalysts, with expansive void volume and fully open network architecture, provide superior mass and heat transfer capabilities, and effectively mitigate the generation of CO and CH, offering a significant advantage in FT synthesis. This work presents a new strategy for the development of efficient catalysts in high exothermic catalytic reactions.