Preparation of polysulfone-graft-monoazabenzo-15-crown-5 ether porous membrane for lithium isotope separation

A novel polysulfone- graft -monoazabenzo-15-crown-5 ether (PSF- g -BN15C5) polymer was prepared via nucleophilic substitution reaction and characterized by FT-IR, 1 H NMR, TGA, and XPS. The non-induced phase separation was employed to fabricate PSF- g -BN15C5 porous membrane with sponge-like structure for lithium isotope separation. The effects of lithium salt, temperature and immobilization amount of crown ether on distribution coefficient and separation factor were explored. Results showed that a maximum separation factor obtained from the solid–liquid extraction system of H 2 O-LiI/PSF- g -BN15C5 was up to 1.049 ± 0.002. Furthermore, the light isotope 6 Li was enriched in the membrane phase owing to the stronger bonding environment.