Abstract
The Bureau of Mines has devised techniques to recover lithium from geothermal brines as the chloride. More than 99 pct of the lithium was precipitated from a brine containing 170 mg/l li by adding a solution of alcl3 and increasing the ph to 7.5 With lime slurry. The li-al precipitate was dissolved in hcl and sparged with gaseous hcl to recover the alcl3; this resulted in a solution containing licl and cacl2. The solution was evaporated at 100 deg c to obtain a mixture of the chlorides from which 97 pct of the lithium was recovered and 90 pct of the calcium was rejected by leaching with tetrahydrofuran. The licl recovered by evaporation of the tetrahydrofuran was purified by dissolution in water and treatment with oxalic acid. The final licl solution contained 89 pct of the lithium originally present in the brine and had a purity of 99.9 pct.
