Showing papers by "Kenta Ooi published in 1983"

Treatment of uranium solution

Abstract: PURPOSE:To concentrate uranium from a dilute uranium solution, and to recover the acid or alkali contained in the solution, with a simple procedure, in high efficiency, by filtering the solution under pressure with an organic polyelectrolyte membrane. CONSTITUTION:Dilute U solution containing an acid or an alkali is separated into a solution of the acid or alkali and a concentrated U solution by filtering with a polyelectrolyte membrane under pressure. The polyelectrolyte used as the filter membrane is a polymer compound having dissociable group such as carboxylic acid residue, sulfonic acid residue, phenolic hydroxyl group, phosphoric acid residue, ammonium residue, etc. in the molecule. An ultrafiltration membrane such as acetyl cellulose membrane or polycarbonate membrane bonded with polyelectrolyte and charged pigment, etc. may also be used as the filter membrane. The acid or alkali, and U are concentrated in the filtrate and in the remaining liquid, respectively, by the filtration treatment under pressure.

Recovering method of lithium from gerothermal water and brine

Abstract: 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 deg.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.