METHOD OF SORPTION EXTRACTION OF LITHIUM FROM LITHIUM-CONTAINING BRINES Russian patent published in 2020 - IPC C01D15/04 C02F1/28 B01D15/04 B01D24/16 

FIELD: hydrometallurgy.

SUBSTANCE: invention relates to hydrometallurgy of lithium and can be used for extraction of lithium from natural brines, process solutions and waste water of oil and gas producing, chemical, chemical-metallurgical and biochemical industries. Lithium concentrate is obtained by way of sorption enrichment of the brine by lithium in a sorption-desorption concentration module using a granular sorbent based on a chlorine-containing variety of aluminum and lithium double hydroxide. Granite sorbent saturated with lithium chloride is washed from brine. Desorption of lithium chloride from the sorbent is carried out to obtain a primary lithium concentrate – lithium chloride solution with magnesium and calcium impurities. Primary lithium concentrate is directed to nanofiltration unit selective with respect to magnesium and calcium. Concentrate after nanofiltration plant is fed repeatedly into stream of initial lithium-containing brine. Filtrate after nano-filtration unit is directed for further concentration on lithium chloride.

EFFECT: higher efficiency of sorption extraction of lithium from lithium-containing brines due to elimination of loss of lithium, simplification of technology by reducing the number of technological operations and amount of chemical reagents used.

1 cl