METHOD OF EXTRACTING POTASSIUM CHLORIDE Russian patent published in 2012 - IPC C01D3/08 C05D1/04 

FIELD: chemistry.

SUBSTANCE: invention relates to the technique of extracting potassium chloride from potassium-containing material with impurities of sodium chloride, insoluble and organic compounds. The method involves thermal treatment of potassium-containing material at temperature 280-700°C and subsequent dissolution of the thermally treated potassium-containing material in a solution heated to 95-105°C to obtain a suspension. The suspension is separated by thickening and filtration to obtain a clear solution. The clear solution is cooled on an apparatus with controlled vacuum crystallisation. Potassium chloride is then crystallised from the obtained solution. The potassium chloride is then classified into coarse crystalline and fine crystalline fractions. The fine crystalline fraction is diluted with water and then taken for crystallisation. The crystalline product is separated by thickening and filtration and dried with classification of the end product.

EFFECT: processing of fine classes of concentrate froth to obtain crystalline high-quality potassium chloride which does not contain fractions smaller than 0,2 mm.

2 cl, 2 tbl, 2 ex