Process for producing geometric shaped catalyst bodies

A process for producing geometric shaped catalyst bodies K which comprise, as an active material, a multielement oxide I of the general stoichiometry I

• [BiaZ1bOx]p[BicMo12FedZ2eZ3fZ4gZ5hZ6iOy]1 (I),
• where
• Z1=tungsten or tungsten and molybdenum, with the proviso that at least 10 mol % of the molar total amount of Z1 is tungsten,
• Z2=one element or more than one element from the group consisting of nickel and cobalt,
• Z3=one element or more than one element from the group consisting of the alkali metals, the alkaline earth metals and thallium,
• Z4=one element or more than one element from the group consisting of zinc, phosphorus, arsenic, boron, antimony, tin, cerium, vanadium and chromium,
• Z5=one element or more than one element from the group consisting of silicon, aluminum, titanium, tungsten and zirconium,
• Z6=one element or more than one element from the group consisting of copper, silver, gold, yttrium, lanthanum and the lanthanides,
• a=0.1 to 3,
• b=0.1 to 10,
• d=0.01 to 5,
• e=1 to 10,
• f=0.01 to 2,
• g=0 to 5,
• h=0 to 10,
• i=0 to 1,
• p=0.05 to 6, and
• x, y=numbers determined by the valency and frequency of the elements in I other than oxygen,
• in which
• a finely divided mixed oxide BiaZ1bOx with a particle diameter d50A1, as starting material A1, is preformed with the proviso that 1 μm≦d50A1≦100 μm;
• sources of the elements other than oxygen in the component T=[BicMo12FedZ2eZ3fZ4gZ5hZ6iOy]1 of the multielement oxide I are used in an aqueous medium to obtain an intimate aqueous mixture M, with the proviso that
• each of the sources used, in the course of preparation of the aqueous mixture M, passes through a degree of division Q for which its diameter d90Q is ≦5 μm, and
• the aqueous mixture M comprises the elements Bi, Mo, Fe, Z2, Z3, Z4, Z5 and Z6 in the stoichiometry I*
• BicMo12FedZ2eZ3fZ4gZ5hZ6i (I*);
• the aqueous mixture M, by means of drying and adjusting the degree of division d90A2, is used to obtain a finely divided starting material A2 with a particle diameter d90A2, with the proviso that 400 μm≧d90A2≧10 μm;
• starting material A1 and starting material A2, or starting material A1, starting material A2 and finely divided shaping assistant, are mixed with one another to form a finely divided starting material A3, with the proviso that the starting material A3 comprises the elements other than oxygen introduced into the starting material A3 via starting materials A1 and A2 in the multielement oxide I in the stoichiometry I**
• [BiaZ1b]p[BicMo12FedZ2eZ3fZ4gZ5hZ6i]1 (I**),
• finely divided starting material A3 is used to form geometric shaped bodies V, and
• the shaped bodies V are treated thermally at elevated temperature to obtain the geometric shaped catalyst bodies K,
• wherein the stoichiometric coefficient c satisfies the condition 0<c≦0.8, and
• wherein all particle diameters are base on volume-based particle diameter distribution determined according to ISO 13320 at a dispersion pressure of 2 bar absolute.