To make the efficient contact gaseous phase oxidation of a low mol.wt. org. compd. possible by using a multiple metal oxide material which has a multiphase structure expressed by the specific formula and contains molybdenum, vanadium and ≥1 kinds of tungsten, niobium, tantalum, chromium and cerium.
This multiple metal oxide material is expressed by the formula [A]p[B]q (where, A denotes Mo12VaX1bX2cX3dX4eX5fX6gOx (active phase); B denotes X712CubHiOy (promoter phase); X1 denotes W, Nb, Cr, etc.; X2 denotes Cu, Ni, Co, etc.; X3 denotes Sb, etc.; X4 denotes Na, K, etc.; X5 denotes Ca, Sr, Ba, etc.; X6 denotes Si, Al, Ti, etc.; X7 denotes Mo, W, etc.; (x), (y) are each the number determined by the valency and frequency of the elements exclusive of oxygen]. The three-dimensionally spread ranges A, B of the components [A]p, [B]q are distributed relatively and similarly like in the mixture composed of the fine A and the fine B with each other.
ANDOREASU TEENTEN
RASHIYURO MAROJI
