Molybdenum promoted vanadium-antimony-oxide based catalyst for selective paraffin ammoxidation

A process of manufacturing acrylonitrile or methacrylonitrile by the catalytic reaction in the vapor phase of a paraffin selected from propane and isobutane with molecular oxygen and ammonia by catalytic contact of the reactants in a reaction zone with a catalyst, the feed composition having a mole ratio of the paraffin to ammonia in the range of from about 2.5 to 16 and a mole ratio of paraffin to oxygen in the range of from about 1.0 to 10, wherein said catalyst has the elements in the proportions indicated by the empirical formula: VSbmAaMobDdOx where A is one or more of Ti, Sn, Fe, Cr and Ga; D is one or more of Li, Mg, Ca, Sr, Ba, Co, Ni, Zn, Ge, Nb, Zr, W, Cu, Te, Ta, Se, Bi, Ce, In, As, B and Mn; m equals 0.8 to 4; a equals 0.01 to 2; 0 < b < 0.005; d is 0 to 2; x is determined by the oxidation state of the cations present, and the catalyst has been heat treated at a temperature of at least 780 DEG C.