METHOD OF SEPARATING POTASSIUM CHLORIDE AND SODIUM CHLORIDE Russian patent published in 2012 - IPC C01D3/08 B01D9/02 B01D61/00 

FIELD: chemistry.

SUBSTANCE: method of separating potassium chloride and sodium chloride involves (a) obtaining a solution of said salts, which is heated to at least 50°C, (b) removing water from the obtained solution via membrane distillation using a waterproof membrane and precipitation of sodium chloride, (c) separating the precipitated sodium chloride from the solution, (d) cooling the solution with precipitation of potassium chloride, (e) separating potassium chloride from the solution. The solution which remains after step (e) is heated through heat exchange with the solution fed to step (d) and recycled. In another version, the solution which remains after step (e) is mixed with water removed at step (b), heated and used at step (a).

EFFECT: invention enables to remove water completely from process streams, thus preventing its loss, and also enables extraction of potassium chloride.

12 cl, 3 dwg