METHOD OF PRODUCING LITHIUM HYDROXIDE MONOHYDRATE FROM BRINES Russian patent published in 2020 - IPC C01D15/02 

FIELD: manufacturing technology.

SUBSTANCE: invention relates to production of LiOH⋅H₂O from lithium-bearing polycomponent hydromineral raw material sources. Method involves filtration of lithium-bearing brine contaminated with suspended particles with regeneration of filters and processing of spent regenerate and production of productive lithium-bearing brine, extraction from brine of lithium chloride in form of primary concentrate on sorption-desorption modules, nanofiltration cleaning of primary lithium concentrate from magnesium, calcium and sulphate ions. Primary lithium concentrate by reverse-osmotic, electrodialysis concentration, reagent, ion-exchange purification from impurities with subsequent thermal concentration is brought to productive lithium chloride concentrate, which by membrane electrolysis is converted into LiOH solution. LiOH solution is evaporated and LiOH⋅H₂O crystallized.

EFFECT: invention eliminates loss of lithium during production, makes it possible to produce concentrated by-products hydrochloric acid and lithium carbonate as by-products, higher output of commercial product with reduced operating costs, reduced amount of solid production wastes and wider range of lithium-bearing raw material sources suitable for production of LiOH⋅H₂O.

3 cl, 1 dwg, 3 tbl, 5 ex