| abstract |
An improved process for preparing a silver catalyst which comprises impregnating a porous alumina support with a silver salt, preferably silver nitrate, by contacting a quantity of the support with an aqueous solution of the salt in sufficient amount to be completely absorbed by said support while under a vacuum. A dispersing agent is also employed in the aqueous silver salt solution. The support is dried by heating, e.g. 100° C., under vacuum and then, while still under vacuum, impregnated with a reducing agent employing an amount sufficient to be completely absorbed by the support. Subsequent heating at a higher temperature, e.g. 250° C., reduces the silver salt to silver metal. A catalyst is produced which, when employed for the oxidation of ethylene, permits the process to run 5°-10° C. cooler at the normal conversion and also gives an improved yield. |