Contact us
 |
[email protected] |
 |
3275638434 |
 |
 |
| Paper Publishing WeChat |
Useful Links
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License
Article
Determination of Plutonium Isotopes in Radioactive Waste Contaminated with Uranium and Thorium
Author(s)
Raguso Damiano, Dell’Omo Emiliano, Colavolpe Giulia and Gentile Fabiana
Full-Text PDF
XML 950 Views
DOI:10.17265/2162-5263/2023.03.003
Affiliation(s)
Nucleco spa, Via Anguillarese 301, 00123 Rome, Italy
ABSTRACT
Nucleco is the Sogin Group’s Italian leading company in the sector of radiological services, radioactive waste management, decontamination and reclamation of industrial sites and nuclear power plants. Nucleco is 60% owned by Sogin and 40% by ENEA—National Agency for New Technologies. The waste characterization carried out by Nucleco SpA includes a large variety of radionuclides belonging to the gamma, beta and alpha emitter families. The determination of Uranium and Plutonium isotopes plays a key role in the waste characterization. Nucleco SpA has distinguished itself in characterizations of radioactive waste in complex and nuclear plant matrices. These matrices have large amounts of alpha emitters, in particular isotopes of Uranium, Thorium and Plutonium. A significant presence of U238 results in such a large amount of Th234 (and daughters) that interferes with the determination of Pu241. Hence, there is the need of finding a pre-treatment, extraction and subsequent purification technique that would allow Th234 to be detached and thus Pu241 to be determined in complex high-activity matrices. The above elements are extracted using chromatography columns. An isotope of the element to be analyzed, with known activity, is added at the beginning of the process to determine the extraction yield. Before being eluted into the column, the sample undergoes a series of treatments in order to be purified of any interferents. The method developed by Nucleco involves the oxidation of Pu at valence +6 and the subsequent precipitation, in fluorides form, of the elements with valence +4 and +3 (i.e. Th234). Pu241 is then measured by LSC (Liquid Scintillation Counting), while the other isotopes are measured by alpha spectrometry after electrodeposition on a metal plate.
KEYWORDS
Plutonium, thorium, purification, liquid scintillation, LSC, alpha emitters, beta emitters.
Cite this paper
References