Aqueous soluble ‘N′ donor heterocyclic ligands for the mutual separation of Am3+ and Eu3+: Solvent extraction, flat sheet supported liquid membrane and hollow fiber microextraction studies

Abstract Preferential stripping of the trivalent actinide ions such as Am(III) from the organic extract containing a mixture of Am(III) and Eu(III) by a suitable separation method is one of the most challenging areas of research which can find application in the radioactive waste management scheme. In the present study, a comparative evaluation of aqueous soluble tetrasulphonated derivatives of bis-triazinyl pyridine (BTP, LI), bis-triazinyl bipyridine (BTBP, LII) and bis-triazinyl phenanthroline (BTPhen, LIII) was done for the preferential stripping of Am(III) from a mixture of Am(III)/Eu(III) in the N,N,N′,N′-tetra-n-octyl diglycolamide (TODGA) extract. The results obtained in the solvent extraction studies were used for setting up of flat sheet supported liquid membrane based separation systems where the feed phase contained 1 M HNO3 spiked with the 241Am and 152,154Eu radiotracers while the receiver phase contained 0.01 M solutions of the aqueous soluble complexing agents in the presence of 1 M HNO3. Analogous studies were carried out using polypropylene hollow fibers leading to micro extraction of both Am(III) and Eu(III) and preferential stripping of Am(III) where promising separation behavior was observed, especially in the cases of LI and LIII with the DF values of 66 and 72, respectively for Am3+ over Eu3+ along with >80% recovery of Am.