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BIBTEX RIS

Automated flow systems for total and isotopic analysis of uranium and thorium in samples of environmental interest – A review

2023; Elsevier BV; Volume: 166; Linguagem: Inglês

10.1016/j.trac.2023.117146

1879-3142

Jessica Avivar, Caio S.A. Felix, Valfredo Azevedo Lemos, Rennan G.O. Araújo, Sérgio L.C. Ferreira, Vı́ctor Cerdà,

Radioactive element chemistry and processing

As a result of the different uses of radioactivity during the last decades, there has been an increase in the concentration of natural and artificial radionuclides in the environment. This together with some accidents with high impact on the public opinion (e.g. Chernobil and Fukushima) has led to establish or increase environmental radioactivity monitoring programs. Actually, present trends in legislation and research are focused in the development of accurate, precise, reliable and rapid analytical methods with low limits of detection (LOD) to determine radionuclides, such as thorium and uranium, in environmental samples. In this paper, two comprehensive reviews and four automated analytical systems for total and isotopic thorium and uranium determination are presented. The developed methods have been applied to environmental samples with low concentrations of the above-cited chemical elements. These methodologies have been automated exploiting multicommutated flow techniques, such as Multisyringe Flow Injection Analysis (MSFIA), Multipumping Flow (MPFS) and Lab-on-valve (LOV) systems, which provide minimal sample handling, low reagent consumption, waste generation and a high frequency of analysis. Long path length spectrophotometry and ICP-MS have been implemented in the developed methods as detection techniques instead of radiometric detectors in order to obtain fully automated, low cost and fast thorium and uranium determinations.