[2C01-03] Aqueous Separation and Aanalytical Technique 2

[2C02] Study on Improvement in Durability of Microcapsules for Recovery of Uranium from Seawater

*Shion Matsumoto¹, Masanobu Nogami¹, Chikage Abe² (1. KINDAI UNIVERSITY, 2. Tohoku University)

Keywords:triphosphine trioxide, uranium, seawater

Alginic acid crosslinked with Ca(II) (CaALG) has successfully been applied to the recovery of radionuclides from high-level radioactive liquid wastes. We have been investigating the recovery of uranium from seawater by using BaALG-based microcapsules (MCs), where Ca(II) is replaced by Ba(II) and triphosphine trioxide, an extractant with unusual high selectivity for U(VI) in acidic media of low concentrations, is encapsulated. It was found in NaCl system that cleavage of crosslinkage resulting from replacement of Ba(II) by Na(I), followed by leaching of the extractant was not negligible. While, it was also revealed that the leaching could be suppressed by encapsulating a low polar compound together with the extractant.