Ring halogenated aromatic carboxylic anhydrides prodn - using vanadium pentoxide carrier catalyst in gas phase oxidn of aromatic halohydrocarbons

摘要

Catalyst consisting of an inert carrier and V2O5 is used in the prodn. of ring-halogenated aromatic carboxylic anhydrides from aromatic hydrocarbons, with =2 adjacent 1-4C aliphatic gps. and =1 halogen atom in the aromatic ring, by gas phase oxidn. at 250-550 degrees C in the presence of air and catalysts contg. V in oxidised form, as in parent patent. Suitable carriers include Al2O3, SiO2, silicates, SiC, ZrO2 and ThO2, pref. in spherical form and pref. with a rough surface.