Synthesis of stable and low-CO(2) selective ε-iron carbide Fischer-Tropsch catalysts

The Fe-catalyzed Fischer-Tropsch (FT) reaction constitutes the core of the coal-to-liquids (CTL) process, which converts coal into liquid fuels. Conventional Fe-based catalysts typically convert 30% of the CO feed to CO(2) in the FT unit. Decreasing the CO(2) release in the FT step will reduce costs and enhance productivity of the overall process. In this context, we synthesize phase-pure ε(′)-Fe(2)C catalysts exhibiting low CO(2) selectivity by carefully controlling the pretreatment and carburization conditions. Kinetic data reveal that liquid fuels can be obtained free from primary CO(2). These catalysts displayed stable FT performance at 23 bar and 235°C for at least 150 hours. Notably, in situ characterization emphasizes the high durability of pure ε(′)-Fe(2)C in an industrial pilot test. These findings contribute to the development of new Fe-based FT catalysts for next-generation CTL processes.