| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing acrolein and acrylic acid by oxidizing propylene in the presence of a molybdenum-bismuth-iron based composite oxide catalyst in a gas phase, by which the acrolein and the acrylic acid can stably be produced in high yields over a long period in a state depressing the sublimation of the molybdenum component. SOLUTION: This method for producing the acrolein and the acrylic acid, comprising oxidizing propylene with molecular oxygen or a molecular oxygen- containing gas in the presence of a catalyst in a gas phase, is characterized by using several kinds of molybdenum-bismuth-iron based composite oxide catalysts having a constant Fe/(Co+Ni) ratio and containing Co and Ni in various amounts as the catalyst, charging the composite oxide catalysts into a fixed bed reactor so that the Co/(Co+Ni) ratios of the several kinds of composite oxide catalysts are lowered from the raw material gas entrance side of the fixed bed type reactor to the exit side, and dividing the reactor into two or more reaction zones. |
