Development of a Sorption Technology for Separating Uranium and Rare-Earth Elements

The results of laboratory experiments on the sorption separation of uranium and rare-earth elements from nitrate-phosphate solutions on a solid extractant with an active phase in the composition of the heter-oradical phosphine oxide and di-(2-ethylhexyl)phosphoric acid are reported. This extractant was used to attain high capacity and degree of extraction of uranium from solutions with initial uranium concentration <0.5 g/dm3. The following metrics were studied in the process of sorption concentration of uranium: sorption capacity, kinetics of the sorption process, number of sorption stages, and desorption conditions. The optimal sorption conditions giving high selectivity in terms of uranium and the degree of separation of uranium and rare-earth elements were determined.