Crystalline structure of mixed metal oxide catalysts for propane selective oxidation to acrylic acid

The effects of the preparation procedure on the formation of crystal phases and catalytic performance of the MoVTeNbO mixed metal oxide catalysts in selective oxidation of propane to acrylic acid were investigated. The results show that the preferred drying method is the rotavapor method, which favors the formation of an effective crystal phase and suppresses the formation of impurity phases. The preferred calcination atmosphere is an Ar atmosphere. The MoVTeNb mixed metal oxide catalysts can be obtained by solution method after heat-treatment at 600°C in an Ar atmosphere, via a rotavapor with a warm water bath at 60°C, and a pH value of 4.0. The catalyst with a MoVTeNb molar ratio of 1.0:0.3:0.23:0.12 is the most effective and extremely active.