Development of HCl-free solid-phase extraction combined with ICP-MS/MS for rapid assessment of difficult-to-measure radionuclides, 4; Rapid determination of Pd in concrete rubble

太田 祐貴; Do, V.-K.  ; Banjarnahor, I. M. ; 岩橋 弘之; 古瀬 貴広; 田中 康介  

Ota, Yuki; Do, V.-K.; Banjarnahor, I. M.; Iwahashi, Hiroyuki; Furuse, Takahiro; Tanaka, Kosuke

This paper presents an analytical method for detecting Pd in concrete using inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). Palladium was purified through an HCl-free chromatographic process utilizing Ni-resin, which was optimized for high and stable chemical recovery. Palladium was effectively retained on the Ni-resin when treated with dilute nitric acid and was subsequently eluted with hot concentrated nitric acid. This approach improved elution efficiency and increased the recovery rate to over 90%. The determination of Pd via ICP-MS/MS was performed using NH as a reaction gas. By measuring the mass shift of 51, corresponding to Pd(NH) product ions, we successfully eliminated interference from the isobar Ag. The total interference removal factor for Ag reached approximately 10,000, demonstrating that the method is highly selective and reliable for quantifying Pd. The method detection limit for 107Pd in concrete matrices was estimated to be 0.05 Bq g, indicating its sensitivity to detect low levels of the radionuclide, in compliance with environmental safety regulations. This method is now routinely used to monitor Pd in concrete samples collected from the Fukushima Daiichi Nuclear Power Station.