METHOD OF PRODUCING POTASSIUM NITRATE Russian patent published in 2019 - IPC C01D9/14 B01D9/02 C30B29/10 C01B21/50 C05C5/02 

FIELD: chemistry.

SUBSTANCE: invention relates to production of mineral salts and fertilizers and can be used for production of potassium nitrate. Method of producing potassium nitrate involves converting a solution of a mixture of sodium nitrate with potassium chloride, where sodium nitrate is added to the solution of the initial mixture while heating. Obtained mixture is cooled for potassium nitrate crystallization and separated from recycled solution. After separation of potassium nitrate potassium chloride or mixture of potassium and sodium chlorides is added to solution. Solution is evaporated to form sodium chloride crystals and separated from the recycled solution. Reverse solution having molar ratio of Cl^-:NO₃^- ions, equal to (10–40):(60–90), respectively, is directed to prepare initial mixture. Mass fraction of chloride-ion in the finished product – potassium nitrate crystals is 0.1–0.36 %.

EFFECT: method enables to obtain potassium nitrate with minimum content of chloride impurities.

1 cl, 1 dwg, 1 tbl, 3 ex