METHOD OF REMOVING SULPHUR-CONTAINING RESIDUAL COMPOUNDS FROM STREAM OF ALKALINE MATERIAL (VERSIONS) Russian patent published in 2012 - IPC C02F1/28 C02F1/74 C10G27/06 

FIELD: chemistry.

SUBSTANCE: in one version of the invention, in order to remove residual sulphur-containing compounds, a stream of alkaline material containing sulphur-containing compounds, which is first oxidised and separated, is fed into a post-treatment apparatus. The sulphur-containing compounds are in amount of 500 ppm by weight in form of sulphur. The stream of alkaline material is then brought into contact with a layer of solid adsorbent in the post-treatment apparatus and disulphides, which are fed into the post-treatment apparatus as part of the sulphur-containing compounds in the stream of alkaline material, are adsorbed on the layer of adsorbent. An alkaline stream containing less than 20 ppm by weight (in form of sulphur) sulphur-containing compounds is then output from the post-treatment apparatus. In another version, oxidation and adsorption are combined in order to remove residual sulphur compounds from a concentrated alkaline stream in the presence of a phthalocyanine metal deposited on the solid adsorbent. This method is particularly suitable as post-treatment step in a flow scheme for regenerating alkali.

EFFECT: cheap production of depleted alkali with low content of sulphur impurities.

16 cl, 2 dwg, 1 ex