Gross actinide preconcentration using phosphonate-based ligand and cloud point extraction

• Published in: Journal of radioanalytical and nuclear chemistry Vol. 308; no. 2; pp. 527 - 537
• Main Authors: Labrecque, Charles, Lavergne, Julien Légaré, Larivière, Dominic
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-05-2016; Springer
• Subjects: Chemistry; Chemistry and Materials Science; Diagnostic Radiology; Hadrons; Heavy Ions; Hydrochloric acid; Inorganic Chemistry; Nuclear Chemistry; Nuclear Physics; Phosphonates; Physical Chemistry; Precipitation (Meteorology); Reagents; Surface active agents; Cloud point extraction; Alpha spectrometry; Gross counting; Actinides; ICP-MS
• ISSN: 0236-5731; 1588-2780
• DOI: 10.1007/s10967-015-4447-0

A procedure for the effective separation and determination of the most abundant actinides relevant to the nuclear industry (U, Th, Np, Pu and Am) was developed based on cloud point extraction (CPE) using H
2
DEH[MDP] (
P
,
P
-di-(2-ethylhexyl) methanediphosphonic acid) as a ligand. The extractability of actinides with varying concentrations of nitric acid and hydrochloric acid were assessed. The robustness of the method was demonstrated for environmental matrices such as reference materials and spiked liquid samples for the quantification of the gross actinide content. This analytical strategy may replace traditional sample preparation techniques used in radiological methods for gross measurements of radioactivity, and may act as a rapid screening tool in emergency situations. The developed method is a greener alternative to common radiochemical sample preparation techniques such as co-precipitation or evaporation. The formation of a small-volume surfactant-rich phase containing the complexed actinides enables rapid, highly selective and great enrichment of the analytes in this phase. The proposed method shows good extraction and separation yield compared to existing methods, since the surfactant-rich phase is soluble in water and can therefore be redispersed quantitatively in a medium compatible with mass spectrometry while providing fast isolation of the actinide content. Separation of actinides can be achieved after by wet ashing of the surfactant-rich phase obtained by CPE if coupled to the proper radiochemical separation scheme.