| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method capable of continuing reaction over a long period while keeping high yield without depending on a site where hot spot occurs and even if a raw material gas concentration or a space velocity is high when producing acrylic acid by a catalytic vapor phase oxidation reaction using a fixed bed multi-tube type reactor in which a molybdenum-vanadium-based catalyst is packed. <P>SOLUTION: In the method for producing the acrylic acid by carrying out the catalytic vapor phase oxidation of acrolein with molecular oxygen or molecular oxygen-containing gas by using the fixed bed multi-tube type reactor in which the above catalyst is packed, the catalyst is a granular catalyst using an oxide and/or a composite oxide containing molybdenum and vanadium as essential ingredients and having a hole part, and a catalyst-packed layer of each reactor in the fixed bed multi-tube type reactor is divided into a plurality of reaction zones in the tube-axial direction and the catalyst is packed into respective reaction zones in which hole diameters are different in at least two reaction zones among the plurality of reaction zones. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
