Oxidative Dehydrogenation of Propane over Mg−Mo−O Catalysts

Abstract

Mg−Mo−O catalysts have been investigated with different techniques (XRD, XPS, IR, and EPR spectroscopies) in order to explain the difference in catalytic behavior in the oxidative dehydrogenation of propane to propene. The active site would be a coordinatively unsaturated form of Mo5+. The active Mo5+ could be generated on the surface by propane reduction. The slight excess of MoO3 which is necessary for the catalyst to become an active one probably contributes to the formation of Mo5+.

X-ray spectroscopic fingerprints of reactive oxygen sites at the MoO3(010) surface

“…In particular, molybdenum oxides are known to activate C-H bonds of alkanes, including methane, and catalyzing their selective partial oxidation, a process that otherwise requires extremely high temperatures. In mixed oxides, molybdenum (mainly with vanadium as the other basic catalyst component) is found to be reactive in other important reactions of interest to the chemical industry such as the dehydrogenation of propane to propene [3].…”

Catalytic activity of Mo/MgO catalyst in the wet oxidation of H2S to sulfur at room temperature

“…3 shows Raman spectra of the Mo/MgO catalysts as a function of molybdenum loading. Two weak peaks at 320 and 870 cm −1 can be assigned to a highly distorted tetrahedral MoO 4 2− species with Mo/MgO catalysts below 6 wt.% MoO 3 [23,24]. At a loading of 15 wt.%, together with two bands at 320 and 870 cm −1 , new two peaks are observed at 212 and 990 cm −1 .…”

“…Fig. 2 shows XRD patterns of the Mo/MgO catalysts after calcinations at 460 • C. The sharp diffraction peaks at 2θ = [15]. The intensity of these peaks increases with increase in molybdena loading.…”

“…These have some advantages over other processes in terms of simplicity and performance. The developed processes are using either a V 5+ /V 4+ couple (Stretford and Unisulf) or a Fe 3+ /Fe 2+ couple (Lo-Cat, Lo-Cat II, Sulferox, and Bio-SR) with chemicals for stabilizing the vanadium or iron [11][12][13][14][15][16][17][18].…”

ENHANCED REDUCIBILITY OF Mg-DOPED MoVTeNbOx MIXED OXIDE CATALYSTS FOR PROPANE OXIDATION REACTION

“…The catalyst properties may also be further improved by the introduction of metal ions into the lattice [15][16][17][18][19][20][21]. Promoter such as cobalt has been reported successful in modifying the properties of (VO) 2 (β-VOPO 4 phase).…”