Preparation, structural properties and catalytic selectivity of sulfate-doped (VO)2P2O7 catalysts in the oxidation of n-butane

Sulfate-doped VOHPO4·0.5H2O precursors with molar ratios of 0 > S : V > 0.1 were prepared by three different methods and calcined to the respective sulfate-doped (VO)2P2O7 catalysts in which the distances of the crystal planes parallel to (200) are enlarged. Sulfate doping influences both the crystal structure and the selectivity to maleic anhydride in the oxidation of n-butane. The best catalytic selectivity was achieved for slightly disordered catalysts and moderate lattice distances.