| abstract |
The present invention is a method of flowing a raw material gas mixture consisting of a molecular oxygen-containing gas and a hydrocarbon compound capable of having a substituent in a fixed bed catalyst layer to vapor-phase oxidize the hydrocarbon compound, wherein the raw material gas mixture has a ratio of the gap of the catalyst layer with respect to the flow direction. It is a gas phase oxidation method which distribute | circulates a source gas mixture in the fixed bed catalyst layer which increases sequentially one or more steps from this upstream to downstream. For example, in the method of the present invention, hydrocarbon compounds such as naphthalene, xylene, benzene, toluene, durene, butene, acenaphthene, anthracene, indene or substituents thereof can be gas-phase oxidized with high yield and high productivity. In addition, gaseous oxidation of naphthalene or ortho xylene can be used to produce phthalic anhydride with high yield and high productivity. |