Industrial & Engineering Chemistry Research, Vol.55, No.7, 2202-2209, 2016
Polymer Inclusion Membrane Containing a Tripodal Diglycolamide Ligand: Actinide Ion Uptake and Transport Studies
A cellulose triacetate (CTA)-based polymer inclusion membrane (PIM) containing a C-pivot tripodal diglycolamide (T-DGA) as the carrier extractant and 2-nitrophenyl octyl ether (NPOE) as the plasticizer shows potential for the uptake of actinides from acidic feed solutions. The uptake of actinides (Am3+, Pu4+, Th4+, UO22+) was studied at 1 M HNO3 with PIMs containing 25.6% T-DGA, 53.9% NPOE, and 20.5% CTA. The metal ion uptake followed the trend: Pu4+ > Am3+ > Th4+ > UO22+, which was in synch with the trend reported previously with PIMs containing N,N,N',N'-tetrakis(2-ethylhexyl) diglycolamide (T2EHDGA) as the carrier. The sorbed actinide ion could be desorbed from the PIMs using a solution of alpha-hydroxy-iso-butyric acid (ARIBA). Transport studies carried out with 1 M HNO3 as the feed and 1 M ARIBA (at pH 3.0) as the receiver phase showed the trend: Am3+> Pu4+ > Th4+ > UO22+, which was different than that observed from the uptake studies. Membrane stability was found to be reasonably good.