Abstract: The catalysts were prepared by the method of the co-precipitation. The catalytic performance for selective oxidation of isobutylene to methacrolein was studied by the pH value of solution and calcination temperature during the preparation of catalysts, the content of the vapor in the material and the pressure of reaction during the process of reaction. The physico-chemical properties of the catalysts were characterized by SEM and XPS. The experimental results indicated that: The conversion of isobutylene with the catalyst of pH=3.0 was obvious higher than that with catalyst of pH=1.0 and pH=6.0.The catalyst on calcination temperature of 400℃ had the highest conversion of isobutylene and the catalyst on calcination temperature of 500℃ had the highest selectivity of methacrolein .With the increase of the vapour content the conversion of the isobutylene and the selectivity of the methacrolein improved, enhancing the pressure increased the conversion of the isobutylene simultaneously decreased the selectivity of the methacrolein.

Key words: isobutylene, methacrolein, selective oxidation, catalysts