METHOD FOR SYNTHESISING SODIUM OR POTASSIUM THIOSULPHATE Russian patent published in 2022 - IPC C01B17/64 C01D5/14 

FIELD: chemical processes.

SUBSTANCE: invention can be used in the chemical industry. Method for synthesising sodium or potassium thiosulphate includes absorbing sulphur dioxide by a water-insoluble liquid organic base; bringing the resulting organic solution of SO₂ in contact with an aqueous solution of NaCl or KCl, or a suspension of NaCl or KCl in an aqueous solution, resulting in a concentrated aqueous solution of sodium/potassium sulphite or bisulphite, or crystalline sodium/potassium sulphite or bisulphite and an organic base hydrochloride. The organic base hydrochloride is then neutralised with a solution or suspension of an inorganic base, or CaO, or CaCO₃, resulting in a neutralised organic base reused for the absorption of SO₂. Then the aqueous solution or suspension of sodium/potassium sulphite or bisulphite react with elemental sulphur, resulting in a solution or suspension of sodium or potassium thiosulphate.

EFFECT: possibility of increasing the effectiveness of the process and the output of sodium or potassium thiosulfate.

8 cl, 2 dwg, 5 tbl, 8 ex