Effect of hydrotalcite-containing precursors on the performance of Cu/Zn/Al/Zr catalysts for CO2 hydrogenation: Introduction of Cu2+ at different formation stages of precursors

A series of Cu/Zn/Al/Zr catalyst derived from hydrotalcite-containing precursors were prepared by introducing the Cu2+ at different stages of Zn/Al/Zr hydrotalcite-like compounds formation and reconstruction and the catalytic performance for the synthesis of methanol from CO2 hydrogenation was examined. The results showed that the physicochemical properties of the catalysts, such as the Cu2+ content located in the layer structure of precursor, the exposed Cu surface area, the Cu+ and Cu0 content on the reduced surface and the ratio of Cu+/Cu0 were greatly influenced by the Cu2+ introduction procedure. The Cu/Zn/Al/Zr catalyst prepared by adding the Cu2+ into the precursor at the reconstructed stage exhibited the best catalytic performance due to the highest exposed Cu surface area and the ratio of Cu+/Cu0.