METHOD FOR LITHIUM HYDROXIDE PURIFICATION Russian patent published in 2006 - IPC C01D1/28 C01D15/02 

FIELD: chemical industry, in particular technology for lithium hydroxide purification.

SUBSTANCE: claimed method includes lithium hydroxide dissolution in deionized water, three-step sorption purification from mercury and other impurities, filtration, the first boiling down at temperature up to 110°C before crystallization, secondary filtration, boiling down, separation of lithium hydroxide monohydrate crystals from mother liquor in inert gas, and vacuum drying. Boiling down is carried out at 105-107°C and elevated pressure to produce solid/liquid ratio of 1:1. After boiling down pulp is cooled to 25°C with rate of 1.6-1.7 °C/h. After separation of lithium hydroxide monohydrate crystals from mother liquor crystals are washed with lithium hydroxide solution filtered after the first boiling down, wherein washing solution and crystal volume ratio is 1:1. After drying lithium hydroxide monohydrate crystals are screened.

EFFECT: improved method for lithium hydroxide purification.

3 cl, 1 tbl, 1 ex