SEPARATION OF URANIUM FROM LANTHANUM IN MOLECULAR AND IONIC ORGANIC LIQUIDS

We have investigated the separation of uranium from lanthanum in two m olecular organic liquids (sulfolane, TMSO2; ethylene carbonate, EC) an d in one organic ionic melt: ethylammonium nitrate (EAN). A separation is achieved by chemical oxidation and precipitation of oxides in TMSO 2; in this medium, the part of uranium remaining in solution may be re covered by an electrochemical reduction. In EAN, it is required to add Li2O to initiate the oxides precipitation: the separation corresponds to the difference between the solubility products Of UO3(s) and La2O3 (s). Best results are obtained in EC where the insoluble phase corresp onds to an U/La ratio equal to 186 instead of 1.7 in the initial condi tions.