Slurry-phase CO2 hydrogenation to hydrocarbons over a precipitated Fe-Cu-Al/K catalyst: Investigation of reaction conditions

Abstract

The hydrogenation of CO2 to hydrocarbons over a precipitated Fe-Cu-Al/K catalyst was studied in a slurry reactor for the first time. Reducibility of the catalyst and effect of reaction variables (temperature, pressure and H2/CO2 ratio of the feed gas) on the catalytic reaction performance were investigated. The reaction results indicated that the Fe-Cu-Al/K catalyst showed a good CO2 hydrogenation performance at a relatively low temperature (533 K). With the increase of reaction temperature CO2 conversion and olefin to paraffin (O/P) ratio in C2-C4 hydrocarbons as well as the selectivity to C2-C4 fraction increased, while CO and CH4 selectivity showed a reverse trend. With the increase in reaction pressure, CO2 conversion and the selectivity to hydrocarbons increased, while the CO selectivity and O/P ratio of C2-C4 hydrocarbons decreased. The investigation of H2/CO2 ratio revealed that CO2 conversion and CH4 selectivity increased while CO selectivity and O/P ratio of C2-C4 decreased with increasing H2/CO2 ratio.