High temperature mixing

A process for producing an improved catalyst comprising a mixed metal oxide having the empirical formula

• MoaVbNcXdZeOf
• wherein N is at least one element selected from the group consisting of Te and Sb,
• wherein X is at least one element selected from the group consisting of Nb, Ta, Ti, W, Se, Al, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ni, Pt, Bi, B, In, As, Ge, Sn, Li, Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Ba, Ra, Hf, Pb, P, Pm, Eu, Gd, Dy, Ho, Er, Tm, Yb and Lu,
• wherein Z is at least one element selected from the group consisting of Au, Ag, Re, Pr, Zn, Ga, Pd, Ir, Nd, Y, Sm, Tb, Br, Cu, Sc, Cl, F and I, and
• wherein, when a=1, b=0.01 to 1.0, c=0.01 to 1.0, d=0.01 to 1.0, e=0 to 0.1 and f is dependent on the oxidation state of the other elements, comprising:
• (a) admixing compounds of elements Mo, V, N, X and Z and at least one solvent at a temperature greater than or equal to 45° C. to form an admixture, wherein Mo, V, N, X and Z are present in such amounts that the atomic ratio of Mo:V:N:X:Z is a:b:c:d:e, and, when a=1, b=0.01 to 1.0, c=0.01 to 1.0, d=0.01 to 1.0 and e=0 to 0.1;
• (b) removing said at least one solvent from the so-formed admixture to form a catalyst precursor;
• and
• (c) calcining said catalyst precursor to obtain said mixed metal oxide.