Non-contact and selective Pd separation based on laser-induced photoreduction for determination of Pd by ICP-MS; The Relation between separation conditions and Pd recovery

Yomogida, Takumi   ; Asai, Shiho; Saeki, Morihisa*; Hanzawa, Yukiko  ; Horita, Takuma ; Esaka, Fumitaka  ; Oba, Hironori*  ; Kitatsuji, Yoshihiro  

Palladium-107 is a long-lived fission product, which can be found in high-level radioactive liquid wastes (HLLW). Determination of the Pd contents in HLLW is essential to evaluate the long-term safety of HLLW repositories. However, the Pd content in HLLW has not been reported because of difficulties in pretreatment for the measurement. In this study, we investigated applicability of laser-induced photoreduction to HLLW solution: it enables a simple and non-contact separation of Pd. The results showed the recovery of 60% was achieved at the conditions: 40% ethanol, 20 min irradiation, 100 mJ of pulse energy. Additionally, major radionuclides and potentially interfering components in ICP-MS were removed from the simulated HLLW over a wide concentration range of Pd from 0.24 to 24 mg L, showing the applicability of the proposed separation technique to HLLW samples.