SU490489A1 - The method of purification of gases from mercury - Google Patents

Description

This invention relates to methods for sanitizing gases from mercury vapors and a river to mercury from gases.

A known method of purifying gases from mercury vapors by sorption with solutions of salts of divalent mercury with the formation of compounds of monovalent mercury, followed by their oxidation and return to the process head.

The disadvantage of this method is low (50%) degree of use of the sorbent.

In order to eliminate this drawback according to the proposed method, the oxidation of monovalent mercury compounds is carried out with pacTiBopOM persulphate, for example potassium persulphate, at pH 13-14.

This makes it possible to increase the utilization rate of the sorbent to 100%.

Example 1 A 20 ml aqueous solution of NaCl containing 2 g of HgSO2 mercury salt is loaded into a laboratory glass absorber (d 20 mm).

A gas stream containing mercury vapor is passed through an absorber with a fictitious linear filtration rate of 0.2 m / s, making contact of mercury vapor with a sorbent.

After 152 hours, the degree of gas purification decreased from 99.9% to 20-30%. At the same time, almost ALL introduced bivalent mercury turned into calomel (3.04 g).

To 3.04 g of calomel is added 80.cl. 0.1 M solution of potassium persulfate K2S2O8, and then caustic soda to RP 13.5. As a result of processing for 10 min, almost all calomel passes into insoluble mercury oxide HgO, the yield of which is 93.5% (calculated on metal). Part of the mercuric oxide (1.3 g calculated on the metal) is separated from the precipitate and the metal is recovered from it, for example, by heat treatment at 400 ° C (metal yield more than 90%). To the remaining portion of HgO, a 12.5% hydrochloric acid solution is added in an amount necessary to dissolve the mercuric oxide. From the obtained; a mercury vapor absorber is prepared in the south of the solution; its composition is similar to the initial one. The degree of ochgstki gas from mercury vapor for the prepared absorber is the same as for the original.

2 A similar method results in incomplete conversion of calomel to oxide.

mercury

Subject invention

The method of purification of gases from mercury by sorption by salts of divalent mercury with the formation of compounds of monovalent mercury with its subsequent oxidation and return to the head of the process, so that, in order to increase the use of the sorbent monovalent mercury compounds are made with a solution of persulphate, for example potassium persulphate, at pH 13-14.