Development of high performance electrochemical solvent extraction method

高性能電気化学溶媒抽出法の開発

奥垣 智彦*; 北辻 章浩  ; 糟野 潤*; 吉住 明日香*; 久保田 宏紀*; 芝藤 弥生*; 前田 耕治*; 吉田 善行; 木原 壯林*

Okugaki, Tomohiko*; Kitatsuji, Yoshihiro; Kasuno, Megumi*; Yoshizumi, Asuka*; Kubota, Hiroki*; Shibafuji, Yayoi*; Maeda, Koji*; Yoshida, Zenko; Kihara, Sorin*

水相と有機相間に電位差を印加することによりイオンを水相から有機相へ移動させる反応に立脚した、高性能な電気化学溶媒抽出法を開発した。多孔質のテフロンチューブ,銀線及び白金線などから構成される電解セルを製作して用いた。電解によるイオンの移動は迅速であり、ビス-ジフェニルフォスフィニルエタンを含む1,2-ジクロロエタンを有機相に用いたとき、水相中のウラニルイオンの99%以上を電解セルの滞在時間である40秒で有機相に抽出できた。アクチノイドやランタノイド,Sr, Csイオンの電解抽出について詳細を調べた。アクチノイドイオンの酸化状態を調整するためにカラム電極によるフロー電解法を組合せ、アクチノイドの逐次分離を試みた。

A high performance electrochemical solvent extraction method was developed based on the quantitative transfer of ions from an aqueous, W, to an organic solution, O. It was realized by applying a potential difference between W and O. The cell was composed of a porous Teflon tube immersed with O, a Ag wire inserted into the tube, a Pt wire placed outside the tube. When W containing ions was forced to flow through the narrow gap between the tube and Ag wire, and potential was applied, a very rapid quantitative ion transfer was attained. When O containing extractant, more than 99% of U(VI) in W was extracted during the residence (e.g., 40 s) in the cell. The fundamental feature of the extraction system was investigated, taking into account the application of the system to the extraction of actinide, lanthanide, Sr or Cs ions. The use of a column electrode system connected before the extraction system was examined in order to adjust the oxidation state of the element to that desired.