Polymer Inclusion Membranes Containing N,N,N′,N′-Tetra(2-ethylhexyl) Diglycolamide: Uptake Isotherm and Actinide Ion Transport Studies

Abstract

Polymer inclusion membranes (PIMs) containing N,N,N′,N′-tetra(2-ethylhexyl) diglycolamide (T2EHDGA), a branched diglycolamide extractant as the carrier, cellulose triacetate (CTA) as the polymer matrix, and 2-nitrophenyloctyl ether (NPOE) as the plasticizer were evaluated for the recovery of actinide ions such as Am3+, Pu4+, UO22+, and Th4+ from acidic feed solutions. The optimized PIM composition used in this study was 69% T2EHDGA, 17% NPOE, and 14% CTA. Sorption isotherm experiments were carried out using macro concentrations of Eu carrier (100 mg/L) spiked with 152Eu tracer, and modeling of the data was performed. The sorption kinetics data fitted to the pseudo-second-order model and the Langmuir isotherm suggested a monolayer chemisorption mechanism. Transport studies were carried out in a two-compartment cell in which the feed solution was 1 M HNO3 spiked with the respective radiotracer while the receiver compartment contained 1 M α-hydroxy-iso-butyric acid (AHIBA) solution. Slow transport rate and l...