| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing acrylonitrile, in which an acrylonitrile yield is high and lowering of the acrylonitrile yield with time is reduced and long-term stable production can be carried out. <P>SOLUTION: The method for producing acrylonitrile comprises reacting propylene with molecular oxygen and ammonia in the presence of a divalent metal molybdate catalyst in which a ratio (A1/B1) of an X-ray diffraction peak strength A1 derived from an α type divalent metal molybdate crystal phase and obtained by measuring the catalyst before reaction start by X-ray diffraction method to an X-ray diffraction peak strength B1 derived from a β type divalent metal molybdate crystal phase and obtained by measuring a catalyst before reaction start by the X-ray diffraction method is ≥0.05 and ≤0.95 and a ratio (A2/B2) of X-ray diffraction peak strengths in the catalyst during reaction is kept to ≥0.05 and ≤1 after 1,000 or more hrs from reaction start and the formula [(A2/B2)-(A1/B1)] satisfies ≥0.05 and ≤1. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
