Solvent extraction of U(VI) by calixarenes
Titre de la revue : Solvent Extraction and Ion Exchange
Volume : 24
N° : 3
Pagination : 319-330
Date de publication : 01/07/2006
This paper focuses on the solvent extraction of U(VI) traces by 1,3,5-OMe-2,4,6-OCH2CONHOH-p-tert-butylcalixarene (LH3). The global extraction equation of U(VI) has been established. The complex formed in the organic phase is (UO2) (LH) with an apparent extraction constant equal to 7.1×10-5 M(I =0.04 M). Distribution data show that LH3 efficiently extracts U(VI) from NaNO3 media at pH 5 and that the stripping of U(VI) can be achieved in nitric acid solutions. Finally a comparison with previous results obtained with the 1,3,5-OMe-2,4,6-OCH2COOH-p-tert-butylcalixarene (L′H3) shows that the hydroxamate groups are as efficient as the carboxylate ones for uranyl extraction.