SHELL IMPREGNATED CATALYST FOR USE IN THE PRODUCTION OF VINYL ACETATE AND METHOD FOR THE VINYL ACETATE PREPARATION

摘要

A shell impregnated catalyst for use in the production of vinyl acetate from ethylene, acetic acid and an oxygen containing gas is provided. The catalyst consists essentially of: a) a catalyst support having a particle diameter from about 3 to about 7mm and a pore volume of 0.2 to 1.5 ml per gram; b) palladium and gold distributed in the outermost 1.0 mm thick layer of the catalyst support particles; and c) from about 3.5 to 9.5 percent by weight of potassium acetate, with the proviso that a gold-to-palladium weight ratio ranges from 0.60 to 1.25; and d) palladium content higher than 3 grams per liter of the catalyst. Said catalysts are highly selective, during vinyl acetate production, in suppression of side products, e.g. carbon dioxide.