Regenerated mixed metal oxide catalysts

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PURPOSE : A process for enriching element M in a mixed metal oxide catalyst and a mixed metal oxide catalyst with enriched element M are provided to regenerate a mixed metal oxide as a catalyst which reduces the catalyst aging by contacting the mixed metal oxide with an oxidizing gas, and form the regenerated catalyst by selectively enriching or poisoning the mixed metal oxide and passing the catalyst through a regenerator. CONSTITUTION : A process for enriching element M in a mixed metal oxide catalyst comprises the steps of : (a) providing a mixed metal oxide catalyst having the empirical formula AaVbMcXdOe, where A is at least one element selected from the group consisting of Mo and W, M is at least one element selected from the group consisting of Te and Se, and X is at least one element selected from the group consisting of Nb, Ta, Ti, Al, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ni, Pt, Bi, In, Ce, As, Ge, Sn, Li, Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Ba, Ra, Hf, Pb, Pm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, Au, Ag, Re, Pr, Zn, Ga, Pd, Ir, Nd, Y, Sm, Tb, Cu and Sc, wherein A, V, M and X are present in such amounts that the atomic ratio of A : V : M : X is a : b : c : d, and when a=1, b=0.1 to 2, c=0.1 to 1, d=0.01 to 1 and e is dependent on the oxidation state of the rest elements; and (b) re-metallizing the mixed metal oxide catalyst at the scene of labor by feeding a stream containing volatile organometallic compounds containing element M. The mixed metal oxide catalyst is re-metallized by carrying out chemical vapor deposition of element M on the mixed metal oxide catalyst. © KIPO 2008