Mixed-oxide catalysts involving V, Nb and Si obtained by a non-hydrolytic sol-gel route: preparation and catalytic behaviour in oxydative dehydrogenation of propane

One-step non-hydrolytic condensation reactions, starting from VO(O'Pr)(3) a nd NbCl5, have been used for the first time to prepare Nb-V oxide catalysts . Different materials containing the NbVO5 phase at different purity levels have been obtained, after thermal treatments, depending on the experimenta l conditions. The synthetic procedure has also been applied to prepare tern ary Nb-V-Si oxide systems. From preliminary catalytic reaction studies it a ppears that the catalysts so prepared are promising with respect to their i nteresting performances in the oxidative dehydrogenation (ODH) of propane. It has also been found that alpha-Sb2O4, physically blended with the Nb-V o xide materials, could act as an appropriate promoter to improve the catalyt ic performances of these systems. (C) 2000 Elsevier Science B.V. All rights reserved.