| 摘要 |
<p>A catalyst for producing methacrylic acid in a high yield with high selectivity by catalytically oxidizing methacrolein, isobutyraldehyde, or isobutyric acid in a vapor phase. The catalyst comprises as an active catalyst ingredient a heteropolyacid salt comprising a heteropolyacid containing molybdenum, vanadium, phosphorus, copper, cesium, and NH4 as essential active ingredients. It is characterized in that a weak-acid salt of cesium or cesium hydroxide is used as a source of cesium in the active catalyst ingredient and ammonium acetate is used as an NH4 source. The coated catalyst is obtained by supporting the active ingredient on an inactive support such as alumina.</p> |
