Effect of pressure on the mechanisms of the CO2/H2 reaction on a CO-precipitated CuO/ZnO/Al2O3 catalyst

The influence of working pressure on the mechanisms of the CO2/H-2 reaction on a co-precipitated CuO/ZnO/Al2O3 catalyst have been studied at 230 A degrees C and in the pressure range of 1-75 bar. In the CO2 hydrogenation using CuO/ZnO/Al2O3, the products were found to be CO, methanol and water almost exclusively. Only a trace of methane formation was observed. Methanol and carbon monoxide are competitively formed. The former is produced directly from CO2 whatever the pressure whereas carbon monoxide stems either from CO2 directly at high pressure or both methanol decomposition and CO2 directly at low pressure.