METHOD OF PRODUCING CONJUGATED DIENE

PROBLEM TO BE SOLVED: To provide an industrially advantageous method of producing a conjugated diene such as butadiene by catalytic oxidative dehydrogenation reaction of a monoolefin such as n-butene, by which accumulation of a carbon content such as coke on a catalyst during the reaction is prevented, progress of coking is mitigated and stable operation can be continuously carried out.SOLUTION: The method of producing a conjugated diene comprises supplying a mixture gas prepared by mixing a raw material gas comprising a monoolefin having 4 or more carbon atoms with a gas containing molecular oxygen, to a reactor having a catalyst to thereby produce a corresponding conjugated diene by oxidative dehydrogenation reaction, thereby producing a product gas containing the conjugated diene. In the method, the pulverization rate of the catalyst in the reactor defined by an expression (1):pulverization rate (wt.%)={(weight of pulverized catalyst in the reactor)/(weight of the whole catalyst in the reactor)}×100, is 0.0 wt.% or more and 40.0 wt.% or less.