[3I04-07] Development of Extractant

[3I04] Development of Advanced Adsorbent for Uranium Recovery from Seawater Based on Uranyl Coordination Chemistry

(2)Development and Performance Evaluation of Uranium-Selective Pentadentate Planar Ligands

Takumi Mizumachi¹, Minami Sato¹, Masashi Kaneko², Tomoyuki Takeyama¹, Satoru Tsushima^3,1, *Koichiro Takao¹ (1. Tokyo Tech, 2. JAEA, 3. HZDR)

Keywords:Coordination Chemistry, Uranium Recovery from Seawater, Stability Constant, Separation Factor

On the basis of coordination chemistry of uranyl ion (UO₂²⁺), we have developed a novel water-compatible pentadentate planar ligands for uranium recovery from seawater, and evaluated them from a view point of stability of a formed complex. Consequently, UO₂²⁺ complexes bearing our new ligands exhibit at least 10¹⁰ times higher stability compared with those of the known amidoxime ligands. Furthermore, separation factors of UO₂²⁺ from most metal ions coexisting in the seawater reach 10³-10¹⁰.