[2B17-20] Aqueous reprocessing

5:40 PM - 5:55 PM JST(8:40 AM - 8:55 AM UTC)

[2B19] Development of mutual separation process of An/Ln(1) An/Ln separation process without addition of alkali solution

*Yuji Sasaki¹, Masahiko Matsumiya Matsumiya², Masashi KUMAGAI Kaneko³, Yoshihiro Kumagai Kitatsuji¹, Yasutoshi Kumagai Ban¹, Yuta Kumagai Kumagai¹ (1. Japan Atomic Energy Agency, 2. Yokohama National University, 3. Osaka University)

Keywords:

An/Ln separation,solvent extraction,DTBA,TODGA,TEDGA,DOODA

We have been developing an effective separation method for actinides (An) and lanthanides (Ln) for the establishment of a nuclear fuel cycle. According to worldwide studies, decontamination factors for An/Ln exceeding 1000 have been achieved using 20 stages of extraction. Therefore, the Japanese separation method should aim to meet these performance levels. The TODGA-DTBA method developed in our laboratory achieves a decontamination factor of over 143 (Am/Sm) through batchwise extraction using 18 organic-phase stages and 20 aqueous-phase stages. However, this method requires DTBA to be in its dissociated form and thus necessitates pH control at approximately 1.3 using an alkaline solution (ethylenediamine). In this study, we re-investigate separation conditions without the use of an alkaline solution. Besides DTBA, we employ water-soluble neutral donors, TEDGA and DOODA. The present results show that the separation factor for Am/Nd is several times higher than that (approximately 10) obtained under the TODGA-DTBA conditions.