| 摘要 |
1,266,624. Oxidative esterification catalysts. KNAPSACK A.G. 22 Sept., 1969 [24 Sept., 1968; 22 Oct., 1968], No. 46567/69. Heading B1E. [Also in Division C2] Catalyst compositions for the preparation of unsaturated esters of carboxylic acids (see Division C2), comprise one or more palladium compounds on a carrier in which at least 80% of the carrier particles have a diameter between 0.1 and 1.5 mm. Optional activators are alkali metal or alkaline earth metal carboxylates, alkali metal hydroxides and carbonates. Other alkali metal or alkaline earth metal compounds yielding carboxylates, and compounds of copper, gold, zinc, cadmium, tin, lead, manganese, chromium, molybdenum, tungsten, uranium, iron, cobalt, nickel, niobium, vanadium, and tantalum. The carriers include silicic acid, kieselguhr, silica gel, diatomaceous earth, aluminium oxide, silicate and phosphate, pumice, silicon carbide, spinels, asbestos or active carbon. Silicic acid catalyst is preferred. Examples describe the preparation of vinyl acetate, propionate and butyrate and alkyl acetate. |
