Catalytic Performance of the Sb–V Mixed Oxide on Sb–V–O/SiO2 Catalysts in Methane Selective Oxidation to Formaldehyde

Sb–V–O/SiO2 catalysts were prepared and investigated in methane selective oxidation with O2 as oxidant. Sb–V–O/SiO2 catalysts are active and selective in methane selective oxidation. The formaldehyde yield obtained on Sb–V–O/SiO2 catalysts is clearly higher than that for VOX/SiO2 and SbOX/SiO2 catalysts. A one-pass formaldehyde yield up to 3% was obtained on Sb–V–O/SiO2 catalysts at 650 °C. XRD and UV Raman studies showed that the phase of Sb–V mixed oxide on Sb–V–O/SiO2 catalysts transformed with decreasing Sb/V ratio from Sb2VO5 to SbVO4/VSb1-XO4-1.5X phase. The Sb–V mixed oxide in Sb2VO5 phase is more active and selective than that in SbVO4/VSb1-XO4-1.5X phase.