Selective oxidation of isobutane to methacrolein over MoVTe mixed oxide supported on SBA-3 and SiO2

SBA-3 and SiO2-supported MoVTe mixed oxide catalysts have been prepared by impregnation and/or direct synthesis methods and tested for selective oxidation of isobutane to methacrolein (MAL). It was found that the supported catalysts showed much higher activity than the bulk MoVTe mixed oxide for the reaction. Among the supported catalysts, better isobutane conversion and MAL yield were achieved on the 3% MoV0.8Te0.23Ox/SBA-3 catalyst prepared by the impregnation method. The catalysts were characterized with BET, XRD, Raman, H2-TPR, XPS and FT-IR of pyridine adsorption. The good performance of the SiO2 and SBA-3 supported MoV0.8Te0.23Ox catalysts was attributed to a combination of different properties: (i) formation of well dispersed active phases on large surface areas of SiO2 and SBA-3 supports, which is beneficial for the isolation of active site and preventing the further oxidation of unstable reaction intermediate as well as product; (ii) improved activity for hydrogen abstraction of C–H bond of isobutane due to the formation of isolated pseudotetrahedral VO4 species.