Investigation of Ternary CuZnM (M = Cr, Ce, Zr, Al) Catalysts in CO2 Hydrogenation for Methanol Synthesis

The hydrogenation of CO2 to methanol over Cu-based catalysts is one of the attractive routes to reduce greenhouse gas emissions and generate high-value-added chemicals. Industrial CuZnAl catalysts possess some shortcomings, but various promoters can enhance the activity and durability of Cu-based catalysts for CO2 hydrogenation. Herein, we systematically investigated the variations in the physicochemical properties of ternary CuZnM (M: Cr, Ce, Zr, Al) catalysts induced by different promoters, as well as their impact on CO2 hydrogenation to methanol. The results demonstrate that the catalytic activity followed the order of CZCr > CZCe > CZZr > CZAl, with CZCr exhibiting the highest stability among them. Combined with XRD, SEM, TEM, H2-TPR, TPD, XPS, Raman findings and the experimental results, the smaller Cu particle size was conducive to increasing the CH3OH yield, and the lower Cu+/Cu0 ratio exhibited better stability in CO2 hydrogenation to methanol reaction. This approach offers theoretical insights and practical solutions for the industrial application of ternary Cu-based catalysts.