Radioactive nuclides recovery from spent solvent in STRAD project, 1; Zr recovered by alkaline solutions

Arai, Yoichi  ; Watanabe, So  ; Kubota, Toshio*; Nomura, Kazunori  

In order to recover U and Pu from the degraded solvents as a part of waste liquid management program STRAD (Systematic Treatments of RAdioactive liquid wastes for Decommissioning), recovery of loaded cations in simulated degraded solvents into alkali solutions were experimentally examined. A target solvent of this study was TRUEX solvent involving CMPO and TBP in n-dodecane. Zr was used as a simulant of Pu, and recovery performance and mechanism of Zr from simulated spent solvent into NaOH or NaCO solutions were evaluated. Zr was recovered in NaOH solution as precipitate, while back extraction of Zr into NaCO solution was progressed by forming carbonate complex. Similar recovery mechanisms are also expected for U and Pu loaded in the solvent.