METHOD OF PURIFICATION OF THE SPENT POTASSIUM FLUORIDE Russian patent published in 2007 - IPC C01D3/02 C01B7/24 C25B1/24 

FIELD: chemical industry; methods of purification of the spent acidic smelt of potassium fluoride.

SUBSTANCE: the invention is pertaining to the method of purification of the spent acidic smelt of potassium fluoride from the tramp iron. The method of purification of the spent acidic smelt of potassium fluoride from the tramp iron consists in its the tramp iron neutralization by potassium hydroxide water solution, filtration of the produced pulp and the filtrate guiding to the stage of preparation of the potassium bifluoride, and the produced - to the treatment with the potassium hydroxide. At that the cake is mixed with the dry potassium hydroxide and the produced mixture is treated with the water at the temperature of 80-90°С and filtered. The filtrate is sent for preparation of the potassium bifluoride, and the sediment - to the land disposal. The technical result of the invention consists in the increased degree of the fluoride-ion extraction of the fluorine-ion, the reduced contents of iron in the filtrate and the reactants consumption.

EFFECT: the invention ensures the increased degree of the fluoride-ion extraction of the fluorine-ion, the reduced contents of iron in the filtrate and the reactants consumption.

3 cl, 3 ex