PURPOSE: To separate and recover Li in an aqueous solution in high yield, by bringing the aqueous solution containing the Li into contact with a specific insoluble phosphate, adsorbing the Li in the solution, and eluting the adsorbed Li with an acidic solution.
CONSTITUTION: An underground brine or geothermal water containing Li is brought into contact with an insoluble tetravalent metallic phosphate formed by reacting a solution of a tetravalent metallic salt, e.g. tin chloride, titanium chloride or zirconium oxychloride, with phosphoric acid. The aqueous solution containing the Li is previously adjusted to ≥7pH, and brought into contact with a tetravalent metallic phosphate at about 100°C to adsorb the Li in the metallic phosphate. The tetravalent metallic phosphate adsorbing the Li is then brought into contact with a dilute acid solution, e.g. hydrochloric acid, at ≤4pH to elute and recover the adsorbed Li.
KATOU SHIYUNSAKU
KITAMURA TAKAO
WADA HIDEO
Next Patent: PREPARATION OF ALUMINUM HYDROXIDE WITH LOW ADHESIVE MOISTURE