Selective oxidation of isobutane and isobutene over vanadium phosphorus oxides

Vanadium phosphorus oxide (VPO) was prepared by using dodecyl amine as surfactant and tested for the oxidation of isobutane and isobutene. Characterization results (BET, XRD, EPR, and XPS) showed that the structure and property of the VPO catalyst prepared by using dodecyl amine as surfactant is considerably different in comparison with the VPO catalyst synthesized without dodecyl amine. Catalytic tests showed that relatively high isobutane conversion and desired product selectivity can be achieved over dodecyl amine doping VPO catalyst. It is also found that proper surface V5+/V4+ ratio may be propitious to obtain high selectivity to methacrylic acid for the selective oxidation of isobutane.