Promotive effect of Bi component on propane partial oxidation over MoBiTeO x/SiO 2 catalysts

Abstract

A series of MoTeO x /SiO 2 and MoBiTeO x /SiO 2 catalysts was prepared and catalytic performance of propane partial oxidation to acrolein was tested. The addition of low amount of Bi component to MoTeO x /SiO 2 catalysts was found to significantly promote acrolein selectivity. The catalyst structure and redox properties were investigated by means of X-ray powder diffraction, Raman spectroscopy, in situ Raman spectroscopy, X-ray photoelectron spectroscopy, and H 2-TPR techniques. Results indicate that the Bi promotive effect can be attributed to two possible reasons. One is that the Bi component promotes the dispersal of MoO 3. The isolation effect results in acrolein selectivity increase. Another reason is that Bi doping enhances lattice oxygen diffusion and increases the amount of surface active oxygen, which is responsible for the oxidation of intermediate propylene to acrolein.