2023 Fiscal Year Final Research Report

Simple and rapid quantitation using solid standard for hard-to-dissolve samples with high radioactivity

Research Project

PDF

Project/Area Number	21K04956
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 31010:Nuclear engineering-related
Research Institution	National Institute of Advanced Industrial Science and Technology
Principal Investigator	ASAI Shiho 国立研究開発法人産業技術総合研究所, 計量標準総合センター, 主任研究員 (10370339)
Co-Investigator(Kenkyū-buntansha)	堀田拓摩国立研究開発法人日本原子力研究開発機構, 福島研究開発部門福島研究開発拠点大熊分析・研究センター, 技術・技能職 (20767678) 昆慶明国立研究開発法人産業技術総合研究所, 地質調査総合センター, 主任研究員 (80709634)
Project Period (FY)	2021-04-01 – 2024-03-31
Keywords	ICP-MS / レーザーアブレーション / Sr-90 / 同位体希釈質量分析法 / 不確かさ
Outline of Final Research Achievements	Disposing of the large quantities of adsorbents used to decontaminate wastewater from the damaged reactors at the Fukushima Daiichi nuclear power plant is a major challenge for decommissioning efforts. 90Sr, a significant source of contamination, require the samples to be in a liquid state. However, the process of eluting Sr from the waste adsorbent with high radioactivity is impractical. To address this technical challenge, we considered the use of laser ablation (LA) ICP-MS, which allows for the direct measurement of solid samples. To evaluate the feasibility of LA-ICP-MS for quantifying Sr-90 in waste Sr adsorbent, we prepared a model waste Sr adsorbent. The RSD of the Sr isotope ratios was raging from 1-5 %. The results demonstrate that LA-ICP-MS can effectively quantify Sr-90 in waste Sr adsorbent by optimizing the mixing volume ratio of the Sr-86 spike to the sample.
Free Research Field	放射化学、質量分析、計量学
Academic Significance and Societal Importance of the Research Achievements	高放射性試料では高線量であるがゆえに作業負担が大きく、特殊性に配慮したシンプルな操作で完結できる方法でなければ現場へ適用できない。本課題で提案する固体測定法は、標準固体を試料に「混ぜるだけ」という現場に寄り添ったこれまでにない手法である。Sr-90に限らず幅広い核種に展開することで、測定困難な固体試料の現実的な分析手法としての道を開きたい。