Fe-based bimetallic catalysts supported on TiO2 for selective CO2 hydrogenation to hydrocarbons

A comparative study was carried out on the CO2 hydrogenation activities and product selectivities of the titania-supported monometallic and bimetallic Fe-based catalysts prepared by one-step wet impregnation. Among the monometallic catalysts (Fe, Co and Cu/TiO2), only Fe/TiO2 catalyst exhibited some selectivity to higher hydrocarbons, while Co/TiO2 and Cu/TiO2 were highly selective only to CH4 and CO, respectively. The addition of a small amount of second metal (Co and Cu) on Fe showed the synergetic promotion on the CO2 conversion and the space-time yields (STY) of hydrocarbon products. The incorporation of K and La as promoters can further improve the activity and product selectivity to higher hydrocarbons, indicating that the promoted Fe-based bimetallic catalysts are promising for CO2 hydrogenation to higher hydrocarbons.