Determination of Plutonium Isotopes in Radioactive Waste Contaminated with Uranium and Thorium  

作　　者：Raguso Damiano Dell’Omo Emiliano Colavolpe Giulia Gentile Fabiana 

机构地区：[1]ITIS Giovanni XXIII,State Technical Industrial Institute,Rome 00155,Italy [2]ITIS G.L.Lagrange,State Technical Industrial Institute,Rome 00158,Italy [3]Department Industrial Chemistry,Faculty MM.FF.NN Mathematical,Physical and Natural Sciences of La Sapienza University,Rome 00185,Italy [4]Department Environmental Toxicology,Faculty MM.FF.NN Mathematical,Physical and Natural Sciences of La Sapienza University,Rome 00185,Italy

出　　处：《Journal of Environmental Science and Engineering(B)》2023年第3期128-132,共5页环境科学与工程（B）

摘　　要：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.

关 键 词：PLUTONIUM THORIUM purification liquid scintillation LSC alpha emitters beta emitters. 

分 类 号：O57[理学—粒子物理与原子核物理]