Hydrogenation of CO2 to CH3OH over Cu/ZnO catalysts with different ZnO morphology

Filament-like ZnO and rod-like ZnO were synthesized by hydrothermal method, and used as a component in CuO/ZnO catalysts. These catalysts were tested in hydrogenation of CO2 to CH3OH and compared with the CuO/ZnO catalyst prepared via conventional coprecipitation process. It was found that the activities of these catalysts depended strongly on the morphology of ZnO. CuO/ZnO catalyst prepared with filament-like ZnO exhibited the best activity, the space time yield of methanol reached 0.55 g(-MeOH)/(g(-cat) h) with a 78.2% selectivity of methanol at H-2/CO2 = 3, 240 degrees C, 3.0 MPa and 0.54 mol/(g(-cat) h). Characterizations found that CuO/ZnO catalyst with filament-like ZnO exhibited stronger interaction between ZnO and Cu, and more oxygen vacancies. The performances of these catalysts for CO2 hydrogenation were compared and discussed with their structure. (C) 2015 Published by Elsevier Ltd.