Catalyst for the purification of exhaust gases of internal combustion engines

摘要

A three-way catalyst is described for the purification of automobile exhaust gases formed of an active substance of platinum and rhodium and possibly base metal(s) at a certain weight ratio between the two noble metals and at a certain atomic ratio between the noble and the base metal, which are precipitated onto active aluminum oxide containing certain quantities of CeO2, ZrO2 and Fe2O3, and whereby the catalyst is obtained by impregnating active aluminum oxide, possibly stabilized with alkaline earth metal, with a solution of cerium, zirconium and iron salt which is thereupon calcined in air at 500 DEG -700 DEG C. and then treated after application of an impregnation of salts of the active substance components in a gas current containing hydrogen at temperatures below 650 DEG C.