Liquid-liquid extraction separation of uranium(VI) from associated elements using dibenzo-24-crown-8 from hydrobromic acid medium

Liquid-liquid extraction of uranium (VI) from hydrobromic acid solutions with dibenzo-24-crown-8 in nitrobenzene have been investigated. Uranium(VI) was quantitatively extracted from 6.0-8.0M hydrobromic acid with 0.001-0.01M dibenzo-24-crown-8 and was quantitatively stripped from the organic phase with 0.1-1.0M hydrochloric acid, 0.5-10M nitric acid, 2-10M perchloric acid, 3.0-10M sulfuric acid or 3.0-10M acetic acid. It was possible to separate uranium(VI) from a number of elements in binary mixtures. Most of the elements showed very high tolerance limit. Uranium(VI) was also separated from a number of associated elements in multicomponent mixtures. The method is very simple, selective, rapid and highly reproducible (approximately +/-2%) and was applied to the analysis of uranium in geological samples.