Vanadium phosphorus oxide (VPO) catalyst samples with different P/V molar ratios were prepared in mixture of isobutanol and benzyl alcohol, and their catalytic performance for selective oxidation of propane to acrylic acid (AA) and acetic acid (HAc) by lattice oxygen was investigated in a pulse reactor. The results showed that the AA and HAc only formed over the catalyst samples with n (P)/ n (V)>1 0. The proper n (P)/ n (V) is about 1 1, with which the catalyst samples have the best catalytic performance and maximum reversible oxygen storage capacity. It was also found that the ratio of n (AA)/ n (HAc) increased with the increasing of both the reaction temperature and the n (P)/ n (V) in the catalyst. The XRD results indicated that the title reaction is sensitive to the crystal structure and the active phase is (VO) 2P 2O 7.
