METHOD OF PURIFYING SOLUTIONS OF LITHIUM COMPOUNDS FROM ALKALI AND ALKALI-EARTH METAL CATIONS Russian patent published in 1997 - IPC

FIELD: purification of inorganic chemicals. SUBSTANCE: lithium salt solutions are brought in countercurrent contact with solution of chlorinated cobalt dicarbollide and polyester in nitroorganic solvent. Optimum concentration of polyester is 0.01-0.6 M and that of lithium in aqueous solution does not exceed 5 M. As solvents for polyester, nitrobenzene, nitrotoluene, and nitroethylbenzene are, in particular, used, whereas polyester may be polyethylene glycol, crown ester, kryptand or a mixture of substituted polyethylene glycol esters. When lithium salt solution is in contact with extract, sodium, potassium, calcium, and magnesium impurities go into organic solution. EFFECT: enhanced efficiency of purification. 2 cl, 1 tbl