The reactivity of furan compounds in vapor-phase catalytic oxidation

The reactivity of furan compounds in vapor-phase oxidation with air over a vanadium-molybdenum-phosphorus catalyst on low-porosity corondum has been studied under nongradient conditions. It has been established that the rate of the over-all conversion of the furan compounds studied and the rate of accumulation of maleic anhydride in the cycle decreases in the sequence: furan > furfural > tetrahydrofuran > furfuryl alcohol > 2-methylfuran > 5-methylfurfural, and the selectivity relative to the formation of maleic anhydride decreases in the following sequence: furan > tetrahydrofuran > furfural > furfuryl alcohol > 2-methylfuran > 5-methylfurfural. Some considerations relating to the mechanism of the reaction studied has been put forward.