Process for producing geometric shaped catalyst bodies

摘要

A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry
[Bi1WbOx]a[Mo12Z1cZ2dFeeZ3fZ4gZ5nOy]1,
in which a finely divided oxide Bi1WbOx with the particle size d50A1 and, formed from element sources, a finely divided intimate mixture of stoichiometry Mo12Z1cZ2dFeeZ3fZ4gZ5h with the particle size d50A2 are mixed in a ratio of a:1, this mixture is used to form shaped bodies and these are treated thermally, where (d50A1)0.7·(d90A1)1.5·(a)−1≧820.

主权项

1. A process for producing geometric shaped catalyst body K, which comprises, as an active material, a multielement oxide I having stoichiometry (I):
[Bi1WbOx]a[Mo12Z1cZ2dFeeZ3fZ4gZ5hOy]1  (I), wherein: Z1 is nickel, cobalt, or a mixture thereof; Z2 is an alkali metal, an alkaline earth metal, thallium, or any mixture thereof; Z3 is zinc, phosphorus, arsenic, boron, antimony, tin, cerium, vanadium, chromium, bismuth, or any mixture thereof; Z4 is silicon, aluminum, titanium, tungsten, zirconium, or any mixture thereof; Z5 is copper, silver, gold, yttrium, lanthanum, a lanthanide, or any mixture thereof; a is 0.1 to 3; b is 0.1 to 10; c is 1 to 10; d is 0.01 to 2; e is 0.01 to 5; f is 0 to 5; g is 0 to 10; h is 0 to 1; and x and y are numbers determined by the valency and frequency of the elements in stoichiometry (I) other than oxygen,the process comprising:
(I) preforming a finely divided mixed oxide Bi1WbOx having a particle diameter d50A1 reported in the length unit μm, as starting material A1, with the proviso that 1 μm≦d50A1≦10 μm; (II) mixing sources of the elements other than oxygen in the component T=[Mo12Z1cZ2dFeeZ3fZ4gZ5hOy]1 of the multielement oxide (I) in an aqueous medium, to obtain an intimate aqueous mixture (M), with the proviso that
each of the sources employed, 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, andthe aqueous mixture (M) comprises the elements Mo, Z1, Z2, Fe, Z3, Z4, and Z5 in the stoichiometry (I*)
Mo12Z1cZ2dFeeZ3fZ4gZ5h  (I*); (III) drying and adjusting the degree of division d90A2 of the aqueous mixture (M), to obtain a finely divided starting material A2 having a particle diameter d90A2 reported in the length unit μm, with the proviso that 200 μm≧d90A2≧20 μm; (IV) mixing starting material (A1) and starting material (A2), or starting material (A1), starting material (A2) and finely divided shaping assistant, 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**):
[Bi1Wb]a[Mo12Z1cZ2dFeeZ3fZ4gZ5h]1  (I**), (V) forming a geometric shaped body (V) with the finely divided starting material (A3); and (V1) thermally treating the shaped body (V) at an elevated temperature, to obtain the geometric shaped catalyst bodies (K), wherein the value F of the product
(d50A1)0.7·(d90A1)1.5·(a−1) is ≧820.