METHOD OF CLEANING LITHIUM-7 HYDROXIDE Russian patent published in 2001 - IPC

FIELD: method of cleaning lithium hydroxide. SUBSTANCE: lithium-7 hydroxide solution is subjected to continuous three-stage sorption cleaning from toxic chemical admixtures and evaporation till ratio of solid to liquid reaches level of 1:1 which is necessary for obtaining crystals of required fractional composition. Sorption cleaning of lithium- 7 hydroxide solution is effected at linear rate of from 1.6 to 0.8 m/h at first stage, 0.8 to 0.4 m/h at second stage and 0.4 to 0.2 m/h at third stage. EFFECT: possibility of cleaning lithium-7 hydroxide from toxic chemical admixtures, mercury inclusive and using the solution as passivating additive for loops of heavy-water nuclear reactors. 10 cl, 7 tbl