Supramolecular assembly of ionic liquid induced by UO2 2+: a strategy for selective extraction-precipitation

Abstract In this work, a novel task specific ionic liquid (TSIL) [tributyl(hexyl)phosphonium] 2 [diglycolic acetate] ([P 6,4,4,4 ] 2 [DGA]) was prepared and used to construct a vesicle system. The addition of UO 2 2+ , La 3+ or Th 4+ exhibited different effects on the system. It was found that small amount of UO 2 2+ could induce large-sized aggregation of vesicles and make the precipitation happen, while La 3+ and Th 4+ did not have such capacity. The whole process was characterized by dynamic light scattering and freeze-fracture transmission electron microscopy. An extraction-precipitation strategy was then developed for the selective recovery of UO 2 2+ . Different factors were further studied to optimize the separation efficiency of the extraction-precipitation process.