Synergism of surface Co-rich activated carbon-supported bimetallic Co:Fe catalysts for Fischer-Tropsch synthesis

The present study explores the remarkable potential of activated carbon-supported cobalt-rich bimetallic catalysts (Co:Fe) in Fischer-Tropsch (FT) synthesis. The H2/CO ratio of the syngas was maintained at 1 to simulate biomass gasification. The temperature, pressure, and GHSV were maintained at 240°C, 20 bar, and 20 mL g.cat−1 min−1, respectively. Totally five combinations of mono- and bimetallic catalysts were synthesized by sequential impregnation of Fe followed by Co, offering a novel and facile approach. The characterization studies revealed the Co-rich surface of the bimetallic catalysts with Co3O4 as an active metal species. The FT activity tests revealed the superior performance of the bimetallic catalysts than their monometallic counterparts. The selectivity to C5+ compounds increased with increase in Co content while the CO conversion increased up to 5% Fe content and then decreased further. The maximum CO conversion (67.4%) and C5+ yield (47.6%) were observed for 15Co5Fe/AC. The study provides a unique perspective on the advancement of C5+ fuel production in Fischer-Tropsch synthesis, achieved through the synergy of FTS-active cobalt and WGS-active iron.