LITHIUM CARBONATE PURIFICATION METHOD Russian patent published in 2024 - IPC C01D15/08 C01D7/26 C22B26/12 

FIELD: metallurgy.

SUBSTANCE: invention relates to lithium hydrometallurgy and can be used to produce lithium concentrate by purifying secondary lithium concentrate. Method comprises reacting a secondary lithium concentrate with a sodium carbonate solution or with a potassium carbonate solution to obtain a mother solution and a lithium carbonate precipitate, their separation and lithium carbonate precipitate washing with washing liquids heated to temperature higher than 75 °C and lower than 90 °C. Performing, at least four stages of washing are performed. At the first stage, washing water or solutions obtained at various stages of the entire process of producing Li₂CO₃ are used for washing. At the last stage, flushing liquids are used, selected from the group: distilled water, deionised water, demineralised water, bidistilled water, permeate or mixture thereof. At the rest of the washing stages, the washing liquid coming out of the previous washing stage is used.. Ratio of the volume of the lithium carbonate sediment to the volume of the washing liquid (S:L) at each of the washing steps ranges from 1:5 to 1:7.5.

EFFECT: higher efficiency and efficiency of purification of lithium carbonate with preservation of high purity of end product.

15 cl, 5 dwg, 1 tbl, 8 ex