Precipitation behaviors of fission products by phosphate conversion in LiCl-KCl medium

リン酸塩転換における核分裂生成物の沈殿挙動

天本 一平; 小藤 博英  ; 明珍 宗孝; 高崎 康志*; 矢野 哲司*; 寺井 隆幸*

Amamoto, Ippei; Kofuji, Hirohide; Myochin, Munetaka; Takasaki, Yasushi*; Yano, Tetsuji*; Terai, Takayuki*

RIARで廃塩処理技術として検討されているリン酸塩転換法について、金属電解法から発生する使用済み電解質再生への適用性を評価すべく、FPのリン酸塩沈澱にかかる熱力学的考察と基礎試験を行い、得られた結果から電解質中のFP分離の可能性を述べ、かつFP回収法を提案している。

The separation technique by phosphate conversion of FP from NaCl-KCl or NaCl-2CsCl as the medium of the spent electrolyte of pyroprocessing is being developed at RIAR in Russia. To ascertain the technical feasibility of applying this RIAR's method for recycling of spent electrolyte which composed of FP such as AL, ALE, and REE and 3LiCl-2KCl as the medium, preliminary study was undertaken at JAEA. This study occupies an auxiliary role which is forwarded as a part of FaCT Project of Japan. As a first approach, the thermodynamic analysis to understand the behaviours of FP in the electrolyte was carried out after literature research and acquisition of required thermodynamic properties. Preliminary experiment was then undertaken to observe the conversion behaviours of chlorides to phosphate. In this paper, these results are shown and are evaluated to discern the feasibility of the phosphate conversion method.