Highly efficient V-Sb-O/SiO₂ catalyst with Sb atom-isolated VOx species for oxidative dehydrogenation of propane to propene

Silica supported vanadium–antimony mixed oxide catalyst (V–Sb–O/SiO₂) with the single ⎯⎯O⎯⎯Sb⎯⎯O⎯⎯V⎯⎯O⎯⎯Sb⎯⎯framework was prepared by a two-step impregnation method, in which SbCl₅ and NH₄VO₃ were introduced successively to generate monomeric VOx species isolated by Sb atoms. In the ODH of propane with O₂ as oxidant, the V–Sb–O/SiO₂ catalyst leads to high activity and high propene selectivity but depressed production of COx. At 600 °C, a 65.6% C₃H₆ selectivity with a 40.1% C₃H₈ conversion was obtained and then, a propene yield up to 26.3% was achieved on V–Sb–O/SiO₂ catalyst. This yield is comparable to that for V–Mg–O catalysts, SBA-15/MCM-41supported vanadia catalysts and vanadium-containing mesoporous silica materials