[1C09-12] Aqueous Separation and Analytical Technique 1

[1C10] Study on the aggregation structure of HONTA in the n-dodecane media by soft-X ray absorption spectroscopy

*Yasunori Miyazaki¹, Katsunori Ishii¹, Yuichi Sano¹, Tomohiro Toigawa¹, Masanari Nagasaka², Sho Igaki³, Tatsuo Gejo³, Fumitoshi Kumaki⁴, Jun-ichi Adachi⁴ (1. JAEA, 2. IMS, 3. Univ. of Hyogo, 4. KEK)

Keywords:minor actinide recovery, solvent extraction, soft-X ray absorption spectroscopy, HONTA

Selective recovery of minor actinides (MA) from high-level radioactive liquid waste after spent nuclear fuel reprocessing is a societal concern to reduce the volume and radiotoxicity of radioactive waste. N,N,N’,N’,N’’,N’’-hexaoctylnitrilotriacetamide(HONTA) is one of the extractants that leads to complexation with MA, and has been investigated for separation from rare earth elements (REE). Thus, MA selectivity will be understood by the interaction of acid with respect to the complexation structure and aggregation of HONTA in the organic phase. In this study, the coordination sites of HONTA are identified from the peak shifts by soft X-ray absorption spectroscopy, and its structural changes are discussed in comparison with the quantum chemical calculations.