CS261061B1 - A method for treating mixed cobalt oxide - Google Patents

Abstract

The method of processing mixed cobalt oxide CO3O4 obtained from cobalt-containing wastes formed in the cyclohenone production process solves the efficient use of the precious metal. The mixed cobalt oxide is used to prepare a catalyst carrier for the oxidation of ammonia to nitric oxide.

Description

The invention relates to a process for the treatment of mixed cobalt oxide CO 3 O 4 obtained from cobalt-containing sludges formed in the cyclohexane oxidation process using a cobalt-based oxidation catalyst.

For the selective oxidation of ammonia to nitric oxide, respectively. cobalt oxides catalysts have recently been used in the manufacture of nitric acid. These catalysts are characterized by high mechanical strength and durability. They are made by forming a catalytically active layer on cobalt-aluminum spinel compounds AO 177 220, AO 173 274. The use of mixed cobalt oxide CO 3 O 4 for the production of a catalyst support is required in order to achieve the above-mentioned catalyst properties.

The carrier is produced using CO3O4 obtained by sophisticated technological processes such as the combustion of metallic cobalt in an oxygen atmosphere, by thermal decomposition of dehydrated cobalt nitrate AO 242 223.

Substituting the CO 3 O 4 thus used for the production of the catalyst support with CO 3 O 4 obtained from cobalt-containing wastes in the cyclohexanone production process is a substantially simplified and streamlined production of the support, which mainly affects the mechanical strength of the catalyst, respectively. its lifetime.

The present invention provides a process for the treatment of mixed cobalt oxide CO 3 O 4 obtained from cobalt-containing sludges formed in the cyclohexane oxidation process using a cobalt-based oxidation catalyst and characterized in that the mixed oxide containing 0.001 to 2% nickel, 0.001 to 2% sodium and 1% by weight of calcium, magnesium, silicon and chromium is disintegrated to particles of 0.004-0.4 mm, preferably 0.01-0.04 mm, and incorporated into an ammonia to nitric oxide oxidation catalyst carrier in an amount corresponding to the content of mixed cobalt oxide in the 5 to 60% by weight.

An advantage of the present invention is the efficient use of mixed cobalt oxide obtained from waste. The simplified and more efficient production of the ammonia to nitric oxide catalyst support retains its required properties.

The process of treating the mixed oxide to produce the ammonia oxidation catalyst support is illustrated in detail in the following examples.

Example 1

50 parts by weight of mixed cobalt oxide obtained from cyclohexanone production wastes and containing 1.3 parts of iron, one part of nickel and sodium, 48 parts of alumina and 2 parts of titanium dioxide to be homogenized and using known additives are used to prepare the catalyst support. molding to form the desired catalyst support.

Example 2

25 parts of CO 3 O 4 prepared from cobalt nitrate and 25 parts of mixed oxide obtained from cyclohexanone production wastes containing 1.5 parts of iron and 0.1 parts of nickel, chromium, magnesium and calcium, 48 parts of aluminum oxide and 2 parts are used to prepare the catalyst support. titanium dioxide. After homogenization of the thus obtained mixture, subsequent shaping and firing, a catalyst support with a content of 48% by weight of C0304 is suitable for further processing to produce the catalyst.

Claims (1)

Process for the treatment of mixed cobalt oxide CO3O4 obtained from cobalt-containing sludges formed in the cyclohexane oxidation process using a cobalt-based oxidation catalyst - characterized in that the mixed oxide with an iron content of 0.01-6%, nickel 0.001-2%, sodium 0.001 to 2%, calcium, magnesium, silicon, chromium The invention is disintegrated to a particle size of 0.004 to 0.4 mm, preferably 0.01 to 0.04 mm, and incorporated into an ammonia to nitric oxide oxidation catalyst carrier in an amount corresponding to a content of mixed cobalt oxide in the carrier of 5 to 10%. 60% by weight.