| abstract |
Provided is a method for regenerating a catalyst for producing methacrylic acid having excellent catalytic activity and sustainability, and a method for producing methacrylic acid with good conversion and selectivity using the regenerated catalyst. . A mixture containing a deterioration catalyst, an ammonium radical, a nitrate radical and water is heat-treated at 100 ° C. or higher, dried and then calcined to produce methacrylic acid comprising a heteropolyacid compound containing phosphorus and molybdenum. Regenerate the catalyst. In the presence of this regenerated catalyst, a compound selected from methacrolein, isobutyraldehyde, isobutane and isobutyric acid is subjected to a gas phase catalytic oxidation reaction to produce methacrylic acid. [Selection figure] None |