Effect of composition of Cu-ZnO-CeO 2 catalyst on its performance for methanol synthesis from CO 2 hydrogenation

Three catalysts, CuO-CeO2 (5:1 molar ratio), CuO-ZnO (5:4 molar ratio) and CuO-ZnO-CeO2 (5:4:1 molar ratio), were prepared by coprecipitation method.The physicochemical properties of the catalysts were characterized by X-ray diffraction (XRD), hydrogen temperature reduction (H2-TPR), CO2 temperature programmed desorption (CO2-TPD), nitrogen adsorption desorption, X-ray photoelectron spectroscopy (XPS), N2O titration.The activity of the catalyst was evaluated in a catalytic microreactor.The results show that, the physicochemical properties and catalytic activity of the ternary CuO-ZnO-CeO2 catalyst are different from that of the binary catalyst, specifically, the strength of surface alkaline sites are increased, the thermal stability is enhanced, the particle size of CuO particles is reduced, the dispersion of copper and the concentration of oxygen vacancies are increased, and the catalytic activity is finally improved. In the CuO-ZnO-CeO2 catalyst, the CuO particle size is 8.2nm, the specific surface area of copper is 68.4m2/g, the copper dispersion is 7.19%, the selectivity and the yield of methanol are 48.6% and 0.057mmol/(g·min), respectively.