Selective transport of cesium using a supported liquid membrane containing di-t-butyl benzo 18 crown 6 as the carrier

Solvent extraction and transport behaviour of Cs(I) across a polypropylene based supported liquid membrane (SLM) using di-t-butyl benzo 18 crown 6 (DTBB18C6) in nitrobenzene as the carrier was investigated. Solvent extraction as well as transport studies were carried out at varying diluent compositions and feed acidities. A diluent containing 2:3 mixture of toluene:nitrobenzene was found to be the most promising. The extracted species conformed to a stoichiometry of 1:1.5 metal to ligand ratio suggesting the extraction of an organophilic ‘sandwich’ complex along with the 1:1 complex. The fission products obtained from an irradiated natural uranium target were found to be poorly transported while Cs-137 got quantitatively transported suggesting the possible application of the separation method for the removal of bulk Cs-137 from the nuclear waste.