Operando DRIFT and In situ Raman Spectroscopic Studies on Aspects of CO ₂ Fischer‐Tropsch Synthesis Catalyzed by Bulk Iron Oxide‐Based Catalysts

Hematite is a suitable precursor to obtain catalytically active iron (oxide) phases for CO2 Fischer-Tropsch synthesis after reductive pretreatment. As concluded from in situ Raman spectroscopy, hydrogen atmosphere the transformation α-Fe2O3 Fe3O4 faster than further reduction Fe (metallic iron). The rate of these steps highly depends on temperature. Starting pure hematite, surface formate species are formed at CO2/H2 gas mixture elevated temperatures, observable by DRIFT-spectroscopy. exposure and CO led carbonate-carboxylate species. Reduced samples with varying contents did not show any adsorbates reaction conditions. same behavior was found during dosage single gases reduced catalysts. formation carbonaceous species, detected could indirectly hint occurrence carbidation especially observed good performing catalyst medium degree.