Patent ID: 6048987
Filing Date: 2000-04-11
Classification: B01J,C07C

Abstract:
Process for producing coated catalysts for the gas-phase oxidation of C.sub.4 -hydrocarbons to maleic anhydride consisting essentially ofpreparing a vanadyl phosphate precursor having a V/P ratio of from 1:0.5 to 1:2 and a mean vanadium oxidation state of from 3.9 to 4.5 in a liquid selected from the group consisting of an aqueous liquid and an organic liquid;drying said vanadyl phosphate precursor;calcining the vanadyl phosphate precursor by heating for several hours at a temperature of from 200.degree. C. to 500.degree. C., to produce a calcined precursor; andapplying the calcined precursor in an aqueous suspension to support bodies to produce the coated catalysts.