A DRIFTS and TPD study on the methanation of CO2 on Ni/Al2O3 catalyst

This study deals with the hydrogenation of CO2 into CH4 and H2O on an Al2O3-supported Ni catalyst with Ni content of 20 wt%. CO2 adsorbates were identified by DRIFTS and CO2-TPD mainly showing the formation of carbonate and carboxylate species. Exposure to H2 indicates that hydrogen carbonate present on the support as well as carbonate presumably adsorbed at the Ni-Al2O3 interface are reactive intermediates in the methanation. Contrary, carboxylate also adsorbed on Ni as well as formate species are acting as spectators.