| 摘要 |
<p>A cyclic method for separating at least one first element E1 present in an aqueous solution from at least one second element E2 present in the same aqueous solution, each cycle comprising co-extracting the elements E1 and E2 from the aqueous solution by bringing the aqueous solution into contact with a liquid organic phase containing a first extractant, adding a second extractant to the liquid organic phase which retains the element E2 in the liquid organic phase during the following step which involves stripping the element E1 from the liquid organic phase and subsequently stripping the element E2 from the liquid organic phase and finally separating and recovering the first and second extractants from the liquid organic phase for re-use. The first and second extractants may be separated from one another by distillation, aqueous solubilisation, cryogenic solidification or by separating two immiscible organic phases. The organic phase may be purified after the first and second extractants have been removed. In use, the method is suitable not only for separating elements from distinct groups, but also for separating elements from the same group. The method may therefore find application in the reprocessing of nuclear fuel, particularly for separating minor actinides from the lanthanides present in the aqueous effluent produced by such reprocessing or in ore refining or in the removal of heavy metals from water.</p> |
