SU493243A1 - Method of preparing a catalyst for the purification of waste gases from sulfur dioxide - Google Patents

Description

(54) METHOD FOR PREPARATION OF CATALYST FOR CLEANING OF EXHAUST GAS FROM SULFUR DIOXIDE

It has a stabilizing effect on the contact properties of the catalyst, preventing the formation of iron and chromium sulfates. In tab. 1 shows the activity of the known

four

and the proposed iron-chromate catalysts on a carrier in the oxidation of sulfur dioxide with a concentration of 0.3% and a gas flow rate of 4000 hours.

Table 1

The amount of the active component (Fe2Oz and Cg2Oz) is significantly reduced, since the highly developed surface of the carrier allows it to be applied in a thin layer, which completely ensures a relatively high activity of the catalyst at all temperatures. The active component in relation to the weight of the catalyst is 35.6% with 12 impregnations, the process of preparing the catalyst is much simpler. The effect of long-term operation on the activity of the iron-chromium oxide catalyst on 7-AljOa at various concentrations of SO2 (up to 1 vol.%) And gas flow rates was investigated. It has been established that the long-term operation of the catalyst for 100 hours has practically no effect on its activity. In addition, Y – A12Oz support of the iron-chromic acid catalyst was carried out for contact oxidation of SO2 to 5Oz. In order to determine the activity of the jelly, the degree of transformed into g SO., Into SOj (in%) at a temperature, ° С

The optimum number of impregnations under the given test conditions is 12. The maximum degree of conversion of SOa to SOa is 95.0% at 500 ° C.

The degree of conversion of SO2 into VOZ at 550 ° C, a gas flow rate of 4000 hours, followed by1TTQ a

schA.

The degree of preconcentration of rotation, 7 ° F3 in gas,

about. %

90,8

0.3 90.2

0.6

85.7 80.1 68.1

Under conditions close to industrial, with a gas velocity of 4000 hours, the effect of fluctuations in the concentration of SOa in the gas mixture is insignificant.

Thus, the catalyst obtained by the proposed method, having increased activity compared with the known and stable operation over time, can use a zinc chromic acid catalyst for Y - АБОз. The dependencies of the degree of oxidation of SOa to 5Oz on the number of carrier impregnation, the concentration of SO2 in the gas mixture and the temperature were studied. The chemical composition of the test catalyst is the following, wt. %: Abz64.5-68.3 Resoz28.5-31.9 Cr2Oz3.2-3.5 Determination of the optimal impregnation number. Test conditions: SOa concentration, vol. % 0.3 Oa Concentration, vol. % 20 Volumetric gas velocity, hourly 4000 Volume of catalyst, Granule size, mm1 The degree of conversion of SOj to 5Oz, depending on the number of impregnations and temperature, is given in Table. 2. Table 2 5 to be effectively used to clean the waste gases from sulfur dioxide. The subject of the invention is a method for preparing a catalyst for purifying waste gases from sulfur dioxide, containing iron and chromium oxides as active components, characterized in that, in order to simplify the technology and to obtain a highly active catalyst, it is prepared by impregnating g-AO2 with solutions of ferrous nitrates and chromium, followed by drying and calcination.