METHOD OF OBTAINING VINYL ESTERS

1,246,015. Supported palladium-gold catalysts. FARBENFABRIKEN BAYER A.G. 17 Jan., 1969 [1 Feb., 1968; 28 Sept., 1968], No. 2754/69. Heading B1E. [Also in Division C2] A supported catalyst containing palladium and gold is prepared by impregnating the catalyst support, simultaneously or successively with or without intermediate drying, with a solution A and a solution B in optional order or with the combined solutions A and B, the solution A containing dissolved salts of palladium and gold and the solution B containing compounds which are able to react on the catalyst support with the noble metal salts of the solution A to form water-insoluble noble metal compounds which are practically free from halogen, sulphur and nitrogen; in quantities which correspond to from 10 to 110% of the absorptive capacity of the catalyst support for these solutions; subjecting the catalyst support impregnated with solutions A and B to a temperature of 0 to 100‹C for 1 to 100 hours which is such that at 95% at least of the impregnated palladium and 95% at least of the impregnated gold is transformed into water-insoluble noble metal compounds, treating the water-insoluble noble metal compounds with reducing agents so as to convert those compounds substantially into the corresponding noble metals and removing the water-soluble compounds which are containing in the catalyst by washing, before or after the reduction step. The catalyst is used in the production of vinyl esters by reacting ethylene, a carboxylic acid with 2 to 4 carbon atoms and oxygen in the gas phase of elevated temperature and normal or elevated pressure.