Synergistic extraction of U(VI) and Th(IV) from nitric acid media with HBMPPT and TBP in toluene

摘要

The synergistic extraction of U(VI) and Th(IV) from nitric acid solution by HBMPPT (4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione) and TBP (tributylphosphate) in toluene was studied. The extraction ability of HBMPPT for U(VI) and Th(IV) was not so high, but when a little TBP was added in, the ability to extract U(VI) and Th(IV) was improved. The extracted complexes may be presented as UO_2NO_3.BMPPT.TBP and UO_2(BMPPT)_2.TBP for U(VI), and Th(NO_3)_3.BMPPT.TBp and Th(NO_3)_2 (BMPPT)_2.TBP for Th(IV), respectively, in the synergistic extraction system. The synergistic effect of HBMPPT and TBP makes the separation coefficient of U(VI) /Th(IV) or U(VI)/Eu(III) reach a high value.