Pertraction of Np⁴⁺ through supported liquid membranes containing two aza-crown ether-based multiple DGA extractants

Multiple diglycolamide (DGA) extractants are reported to be far more efficient than simple DGAones such as TODGA. In view of the importance of Np in the nuclear fuel cycle, there is a need to develop a separation method involving multiple DGA ligands. Two aza-crown ether-based multiple DGA ligands were used in the present study for liquid membrane transport studies using PTFE flat sheets. Solvent extraction studies indicated relatively fast extraction (< 10 min.) of Np (IV) with both the DGA-based ligands at 3 M HNO₃. Oxidation state of Np was adjusted to +4 by using a mixture of ferrous sulfamate and hydroxylamine hydrochloride in the nitric acid medium. The transport of Np (IV) was studied at different feed HNO₃ concentrations using 1x10^-3 M ligand solutions in 5% isodecanol + 95% n-dodecane as the carrier solvent