Development of HCl-free analytical methods for Se in concrete rubble by ICP-MS/MS

Do, V. K.  ; Banjarnahor, I. M. ; Ota, Yuki; Tanaka, Yasuyuki ; Furuse, Takahiro; Tanaka, Kosuke  

The presentation summarizes the results of the development of analytical method for Se in concrete rubble using inductively coupled plasma triple quadrupole mass spectrometry (ICP-MS/MS). Se has been conventionally measured by a liquid scintillation counter (LSC). However, LSC measurement is time-consuming and susceptible to the radioactive interferences from highly radioactive nuclides (Sr, Cs, etc.) coexisting in the samples. In this regard, ICP-MS/MS is a powerful technique, which can effectively eliminate the interferences. In this study, we have developed an HCl-free chemical separation to recover Se and remove the Br isobar. Chemical recovery for Se was around 90%. Also, we investigated the best conditions to measure Se by ICP-MS/MS. The method detection limit of 0.1 Bq/g was achieved indicating that the developed method meets the requirements for the measurement of Se in the radioactive rubble collected at the Fukushima Daiichi Nuclear Power Plant.