Preparation of maleic anhydride derivatives by catalytic oxidation of halogenobutadienes

Abstract

1. 1. A study was made using a laboratory continuous device of oxidation of chloroprene to chloromaleic anhydride (chloromaleic acid) in a fluidized layer of a vanadium-phosphorus catalyst. At the optimum temperature of 470°C, a contact time of 0·80 sec maximum chloromaleic acid yield (32·0 wt.%) is ensured; catalyst output is 203 g of chloromaleic acid/l.·cat·hr. 2. 2. A study was made of oxidation of hexachlorobutadiene to dichloromaleic anhydride on a VP catalyst. The optimum temperature was found to be 480°C, contact time 0·70 sec. Under the conditions observed process selectivity was 80 mole % with 90% conversion of hexachlorobutadiene.