A Comparative Study of Palladium and Copper Catalysts in Methanol Synthesis

Catalytic activity of copper supported on cerium oxide (Cu/CeO2) in methanol synthesis from carbon monoxide and hydrogen at 473 K is similar to that of ceria-supported palladium (Pd/CeO2). Both catalysts contain 0.3 mmol g-1 of the active metals and the activities on a mole basis of the active metals are significantly higher than that of a commercial copper catalyst. Analyses bt EXAFS suggest that the particle size of copper in Cu/CeO2 is similar to that of palladium in Pd/CeO2. The activity of copper supported on silica is very low even at 523 K although the particle size of copper is close to that in Cu/CeO2. Hence, cerium oxide promotes the activity of copper as can be seen in Pd/CeO2.