EXTRACTION METHOD FOR ISOLATION OF LITHIUM FROM AQUEOUS SOLUTIONS CONTAINING LITHIUM, MAGNESIUM AND CALCIUM CHLORIDES Russian patent published in 2023 - IPC C22B26/12 C22B3/26 C22B3/40 C02F1/26 

FIELD: chemical industry.

SUBSTANCE: method for the production of lithium concentrates used in the selective extraction of lithium from multicomponent solutions containing magnesium chlorides and calcium chlorides, for example lithium-containing brines of oil fields, geothermal waters and salt lakes. Selective extraction of lithium is carried out from an aqueous solution containing lithium, magnesium and calcium chlorides. An equimolar 0.1-0.5 mol/l solution of di-tert-butyldibenzo-14-crown-4 and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide in the solvent 1-nitro-3 is used as an extractant for -(trifluoromethyl)benzene extraction.

EFFECT: increase in the selectivity of the extraction system with respect to lithium, namely an increase in separation coefficients β_Li/Mg, β_Li/Ca, when extracting trace amounts of lithium 0.02–0.10 g/l from highly concentrated solutions of magnesium and calcium chlorides.

1 cl, 6 ex