Effect of metal oxide additives on the activity and stability of Cu/ZnO/ZrO2 catalysts in the synthesis of methanol from CO2 and H2

The Cu/ZnO/ZrO2 catalyst has been modified by adding small amounts of B, Ga, In, Gd, Y, Mn and Mg oxides. Two series of catalysts were obtained: series A: by the co-precipitation of basic carbonates and series B: by complexing with citric acid. The oxide additives were found to influence the catalytic activity in the reaction of methanol synthesis from CO2, dispersion of Cu, surface composition of the catalyst, and the stability of catalysts during their operation. In both series of catalysts, the Ga2O3 additive was especially useful. The mechanism of copper sintering and the performance of the oxide additives are discussed.