METHANOL SYNTHESIS AND WATER-GAS SHIFT REACTIONS ON RANEY COPPER-CATALYSTS

The use of Raney copper to catalyse the synthesis of methanol and the water-gas shift reaction is reviewed. The preparation of Raney copper and Raney copper-zinc alloys together with their leaching to form active catalysts is first considered. The production of methanol is promoted by copper and the major - but not the only - role of zinc oxide involves the production of higher and more stable copper surface areas. There is some evidence that the catalytic activity of both methanol synthesis and water-gas shift may be improved by events occurring at the Cu-ZnO interface. It is now clear that carbon dioxide is the major reactant forming methanol under industrial conditions. Both in the water-gas shift and the synthesis reactions, formates appear to be the main intermediates. Raney catalysts have the advantages of high mechanical strength, of regenerability and of producing less side products during methanol synthesis - an important practical consideration. Their applicability to industrial operations would seem advantageous.