Heterogeneous catalyst for oxidation of propylene into propylene oxide

Abstract

A heterogeneous catalyst for oxidation of propylene into propylene oxide in the liquid phase which is a carrier with active components supported thereon, the latter being oxides of scandium, yttrium, indium, gallium, thallium, or rare-earth elements of the lanthanum group, or mixtures of oxides of the above metals. In addition to with said active components, the catalyst can also contain silver, oxides of vanadium, molybdenum, tungsten, bismuth, manganese, or tantalum, or mixtures of the above active components. The method for preparing the catalyst consists in that the carrier is treated with an aqueous solution of a mineral acid or a mixture of mineral acids at 80.degree. to 100.degree.C, washed with water and dried at 300.degree. to 400.degree.C. The thus treated carrier is impregnated with aqueous solutions of salts of the corresponding metals. The impregnated carrier is treated at a temperature of 700.degree. to 800.degree.C. The heterogeneous catalyst ensures high selectivity (to 90 per cent) of the process of oxidation of propylene into propylene oxide in the liquid phase, the conversion of propylene being as high as 30 per cent, and also accelerates markedly the process, ensuring a reaction rate 1.5-2 times higher than the reaction rates obtainable with the known catalyst. Furthermore, said catalyst possesses high mechanical strength.