| abstract |
SUMMARY OF THE INVENTION: The present invention provides a simple method for preparing a catalyst which can maintain methacrylic acid in high yield and high selective, stable methacrylic acid yield over a long period of time by vapor phase catalytic oxidation of methacrolein and the like. It aims to provide. Solution: A method for preparing a catalyst having a heteropolyacid partially neutralized salt containing molybdenum, phosphorus, vanadium, cesium, antimony and ammonia as an active ingredient, wherein the catalyst contains an active ingredient other than antimony as an essential active ingredient. It is characterized by mixing an oxide and an antimony compound. Addition of the antimony compound is also good at the time of slurry preparation. |