Effect of In2O3 on the structural properties and catalytic performance of the CuO/ZnO/Al2O3 catalyst in CO2 and CO hydrogenation to methanol

Abstract

Ternary CuO/ZnO/Al2O3 catalyst was synthesized through coprecipitation method and the effect of indium addition on the textural and catalytic performance was evaluated. The catalysts were tested at 50 atm and 250 °C in H2/CO/CO2, H2/CO and H2/CO2 feed. The presence of In2O3 resulted in structural promotions including enhanced BET and copper surface area, smaller copper crystals and increased oxygen vacancies. On the contrary, unexpected results were observed in catalytic activities in H2/CO/CO2 and H2/CO2 feeds. Pure In2O3 revealed the ability of direct hydrogenation of CO2 to methanol. In addition, it was observed that the addition of palladium into the catalyst remarkably enhanced the CO2 hydrogenation to methanol.