Direct Extraction of Uranium and Plutonium from Oxide Fuel using TBP-HNOComplex for Super-DIREX Process

None

紙谷 正仁 ; 三浦 幸子 ; 野村 和則  ; 小山 智造; 小雲 信哉*; 森 行秀*; 榎田 洋一*

Kamiya, Masayoshi; Miura, Sachiko; Nomura, Kazunori; Koyama, Tomozo; Ogumo, Shinya*; Mori, Yukihide*; Enokida, Yoichi*

Super-DIREX再処理法における直接抽出プロセスの成立性を確認するため,照射済MOX燃料を機械的処理に粉体化し、常圧40-80のTBP錯体でウラン及びプルトニウムを抽出する試験を行った。ウラン及びプルトニウムの抽出及び核分裂生成物との除染について実験データを取得した。

Super-DIREX is a new reprocessing method which has high economical efficiency. Experimental study of this process was started on the direct extraction of U and Pu from irradiated MOX fuel by the supercritical carbon dioxide (SFCO) containing TBP-HNO complex. This report describes direct extraction of U and Pu with TBP-HNO3 complex at atmospheric pressure, as the first test for irradiated fuel, in order to investigate the applicability of SFCO containing TBP-HNO complex. In this test, dependency on dissolution temperature, Pu content, fuel/ TBP-HNO complex ratio and effect of voloxidation were investigated. From these results, TBP-HNO complex was found to be effective in the respect of the recovery of U and Pu. The number of the process step in dissolution and co-extraction is small, and amount of waste can be reduced. It is applicable to the direct extraction in Super-DIREX.