PRODUCTION OF MALEIC ANHYDRIDE

摘要

PROBLEM TO BE SOLVED: To provide a method for producing maleic anhydride in a high yield when a >=4C aliphatic hydrocarbon is oxidized in a vapor phase in the presence of a vanadium-phosphorus-based catalyst to produce maleic anhydride. SOLUTION: In this method for producing maleic anhydride by bringing a raw material gas containing a >=4C aliphatic hydrocarbon and molecular oxygen into contact with a vanadium-phosphorus-based catalyst, nitrogen and an inert gas such as helium or neon having >=800 (10<-4> Wm<-1> K<-1> ) coefficient of thermal conductivity at 700 K are made to exist in the raw material gas. In this case, the total concentration of the nitrogen gas and the inert gas is 60-94.5 vol.% and the ratio of the nitrogen gas to the inert gas (the molar ratio of the nitrogen gas/the inert gas) is 0.05/1 to 1/1.