Propane Oxidative Dehydrogenation on V–Sb/ZrO2 Catalysts

Abstract

The catalytic properties of V-Sb/ZrO 2 and bulk Sb/V catalysts for the oxidative dehydrogenation of propane were studied. Samples were characterized by nitrogen adsorption, temperature-programmed reduction, temperature-programmed pyridine desorption and photoelectron spectroscopic techniques. Vanadia promotes the transition of tetragonal to monoclinic zirconia and the formation of ZrV 2 O 7 . Surface V and Sb oxide species do not appear to interact among them below monolayer coverage, but SbVO4 forms above monolayer. Simultaneously the excess of antimony forms a-Sb 2 O 4 . Activity and selectivity show no dependence on the acidity of the catalysts. However, there is a strong dependence of activity/selectivity on composition; surface vanadium species are active for propane oxidative dehydrogenation and the presence of Sb, affording rutile VSbO 4 phase makes the system selective to C 3 H 6 , this is believed to be related to the redox cycle involving dispersed V 5+ species and lattice reduced vanadium site in the rutile VSbO 4 phase.

Propane Oxidative Dehydrogenation Using Consecutive Feed Injections and Fluidizable VOx/γAl2O3 and VOx/ZrO2–γAl2O3 Catalysts

“…This reduced catalyst can be subsequently reoxidized by gas-phase O 2 in a regeneration step. Regarding propane oxidative dehydrogenation (PODH) in particular, vanadium oxide based catalysts have been mostly used under atmospheres containing O 2 . − …”

Propane Oxidative Dehydrogenation Over Ln–Mg–Al–O Catalysts (Ln = Ce, Sm, Dy, Yb)

“…The oxidative dehydrogenation of propane to propene is one of the potentially important catalytic processes for the effective utilization of light alkanes and has been thoroughly studied in recent times [1][2][3][4][5][6][7][8][9][10][11][12][13][14], propene being an important raw material for the production of polypropylene, acrylonitrile, acrolein and acrylic acid. In spite of this high number of studies there is no up to now a sufficiently active and selective catalyst for the oxidative dehydrogenation of propane to propene that could be used at industrial scale.…”

“…Heterogeneous catalysts for this reaction typically contain vanadium and molybdenum as the critical elements [1][2][3][4][5][6][7][8][9]. Among other oxide systems, those containing rareearth oxides are also reported as active and selective [14][15][16].…”