Patent ID: 6586361
Filing Date: 2003-07-01
Classification: B01J,C07C,C07D

Abstract:
A coated catalyst for the catalytic gas-phase oxidation of aromatic hydrocarbons, comprising, on an inert nonporous support, a catalytically active composition comprising, in each case based on the total amount of catalytically active composition, from 1 to 40% by weight of vanadium oxide, calculated as V2O5, from 60 to 99% by weight of titanium dioxide, calculated as TiO2, up to 1% by weight of a cesium compound, calculated as Cs, up to 1% by weight of a phosphorus compound, calculated as P, and a total of from more than 0 up to 10% by weight of antimony oxide, calculated as Sb2O3, wherein the catalytically active composition is applied in two or more layers, where the inner layer or inner layers have an antimony oxide content of from 1 to 15% by weight and the outer layer has, in contrast, an antimony oxide content which is from 50 to 100% lower, the amount of catalytically active composition of the inner layer or the inner layers is from 10 to 90% by weight of the total amount of catalytically active composition and the amounts of the constituents of the catalytically active composition are to be selected from the stated ranges such that they sum to 100% by weight.