CO2 hydrogenation to methanol on Cu-ZnO/AlLaO with high activity and hydrothermal stability

Abstract

CO₂ hydrogenation to methanol can reduce CO₂ emissions, meanwhile, the prepared methanol can be used as chemical raw material and fuel, and the catalyst Cu-ZnO/Al₂O₃ exhibits good activity. Nevertheless, the activity and selectivity over the Cu-ZnO/Al₂O₃ still need improvement for industrialization. In addition, plenty of water will be generated during CO₂ hydrogenation, which causes deactivation of the catalyst due to the hydrothermal environment in the reaction. To increase the activity and hydrothermal stability, the Cu-ZnO/AlLaO catalyst was prepared by coprecipitation method in this work, which improved the adsorption of CO₂ and inhibited the adsorption of methanol due to the strong surface basicity and the interface structure of Cu and supporter, and then increased the catalytic activity and methanol selectivity. More importantly, various characterization technologies for the structures and surface properties over fresh and hydrothermal treatment catalysts showed that the La₂O₃ added into the catalyst greatly improved the hydrothermal stability.