Liquid-phase oxidation of 1-methoxy-2-propanol with air

The oxidation of 1-methoxy-2-propanol to 1-methoxy-2-propanone with air was studied on lead- and bismuth-promoted palladium catalysts in aqueous alkaline solutions. Several commercial palladium catalysts, supported on carbon or alumina, were tested with regard to their catalytic performance. The highest selectivity (ca. 85% ) was measured for a lead-promoted 5 wt.-% palladium on carbon catalyst. Deactivation was observed with both promoted and unpromoted catalysts likely due to blocking of the active sites by side-products of high molecular weight. The mechanism of deactivation and the role of various parameters, including the nature of the support, the base and metal ion promoters are discussed. “Oxygen-poisoning” of palladium was found to be negligible under the conditions where the oxidation was carried out.