| 摘要 |
PURPOSE:To obtain methacrylic acid in high yield and selectivity, by oxidizing methacrolein with molecular oxygen in the presence of a catalyst containing specific amounts of zirconium and another element added to a catalyst containing phosphorus, molybdenum, vanadium and copper and having high activity, selectivity and long life. CONSTITUTION:Methacrolein is catalytically oxidized with molecular oxygen n the vapor phase to give methacrylic acid. In the process, a catalyst expressed by formula I (X is at least one selected from K, Rb, Cs and Tl; Y is at least one selected from Te, La, B, Ag, Cr, Mg and Ba; a is 0.3-4; c is 0.01-3; d is 0.01-4; e is 0.01-3; f is 0.01-3; g is 0.01-3; h is 0.001-5 when b is 12 and i is the number of oxygen atoms satisfying the valence of each component), e.g. catalyst expressed by formula II, etc., is used. |
