Mechanism of CO formation in reverse water-gas shift reaction over Cu/Al2O3 catalyst

The mechanism of the reverse water-gas shift reaction over a Cu catalyst was studied by CO2 hydrogenation, temperature-programmed reduction of the Cu catalyst and pulse reaction with QMS monitoring. In comparison with the reaction of CO2 alone, hydrogen can significantly promote the CO formation in the RWGS reaction. The formate derived from association of H-2 and CO2 is proposed to be the key intermediate for CO production. Formate dissociation mechanism is the major reaction route for CO production. Cu(I) species were formed from the oxidation of Cu-0 associated with CO2 dissociation.