Work

Method development for plutonium detection in seawater: Selective extraction and sample preparation using actinide resin

Year: 2025

Type: article

Abstract: • A comprehensive AN-resin method was developed for plutonium determination in seawater • Double isotope spike method used to verify complete extraction of Pu from seawater • The pretreatment time was reduced from 1–2 d to 7 h with a high recovery (∼91%) • Sub-μBq/kg detection limits were achieved for 20 L seawater samples • Validation was through interlaboratory comparisons and Korean coastal water analysis A rapid and efficient analytical method was developed for the determination of plutonium in large-volume seawater to overcome the limitations of conventional coprecipitation techniques, which typically require an analysis time of 1–2 d and involve multiple labor-intensive steps. The proposed method integrates microwave-assisted acid digestion, CaF 2 /LaF 3 coprecipitation, and TEVA extraction chromatography with actinide-selective resin (AN-resin) to enable high recovery and significantly reduce the analysis time. Additionally, a key challenge was overcome through method optimization using seawater pre-equilibrated with 239 Pu and 242 Pu as an internal tracer, namely the efficient and rapid separation of Pu from the AN-resin eluate while maintaining its oxidation state. Validation using 20 L seawater samples spiked with 239 Pu achieved recoveries of 86.2 ± 4.4% and 90.5 ± 4.5% for 242 Pu, with an analytical accuracy of 96.7% and precision (relative standard deviation) of 3.1%. The total pretreatment time, including a 2 h preconcentration step, was reduced to ∼7 h, while achieving detection limits of 0.03–0.05 μBq/kg. Interlaboratory comparisons confirmed the robustness of the developed method, while field application to Korean coastal waters yielded 239+240 Pu activities and isotopic ratios consistent with regional monitoring data. This study presents a high-throughput and reliable alternative to conventional methods, offering a versatile platform for emergency response and environmental monitoring of plutonium and other actinides in marine systems.

Source: Journal of Chromatography A

DOI: 10.1016/j.chroma.2025.466559

Authors: Ji-young Park, Dayeong Lee, Ranhee Park, Hyehyun Kim, Jeongkwon Kim

Institutions: Korea Atomic Energy Research Institute, Chungnam National University

Language: English

Topic: Radioactive element chemistry and processing

Subfield: Inorganic Chemistry

Field: Chemistry

Domain: Physical Sciences

SDG: Clean water and sanitation

Open Access status: hybrid

Estimated APC paid: $4,040