Uranium extraction from aqueous solutions by ionic liquids

For determining natural levels of 236U with its environmental abundance of 10−16% rather large sample volumes (∼30 L) are necessary, therefore the conventional radiochemical uranium analysis (pre-concentration and column chromatography) is very time consuming. To speed up the procedure hydrophobic ionic liquids (ILs) were evaluated as a potential extraction agent for uranium from aqueous solutions. High selectivity and efficiency for uranium compared to calcium and magnesium in natural water was achieved with tricaprylmethylammonium thiosalicylate, [A336][TS]. Uranium was stripped successfully from the investigated ILs with 2 M HNO3.