VO x doped Al 2O 3 and AlF 3 – A comparison of bulk, surface and catalytic properties

Abstract

VO x doped aluminium oxides and fluorides with different vanadium contents were prepared by modified sol–gel synthesis techniques. The resulting solid catalysts show an interesting behaviour in the selective oxidative dehydrogenation of propane (ODH). The results of the structural (XRD, MAS NMR, ESR) and surface analysis (BET, Py-PAS, NH 3-TPD) combined with temperature programmed isotope exchange experiments (TPIE) demonstrate that the special catalytic properties of the VO x doped aluminium fluorides arise from a host lattice almost free of oxygen and the presence of a very high concentration of medium–strong acid sites.