The Catalysis of Palladium and Cupric Ion-exchanged Zeolite for Oxidation of Ethylene

Oxidation reactions of ethylene over zeolite loaded with Pd(II) and/or Cu(II) by way of ion exchange were studied in the presence of steam. Neither Pd(II)-zeolite nor Cu(II)-zeolite had good catalytic activity for oxidation of ethylene to acetaldehyde. However, the dual ion catalysts, namely, Pd(II)-Cu(II)-zeolites which were prepared by various ion exchange methods, were found highly active and selective for oxidation of ethylene to acetaldehyde. The degree of conversion of olefins under the same experimental conditions was in the order: ethylene>propylene>1-butene>cis-2-butene≈trans-2-butene. The reaction mechanism was discussed in analogy with that of Wacker-reaction.