Determination of uranium traces in nuclear reactor IEA-R1 pool water

Abstract

IEA-R1 nuclear reactor operation has the routine to control uranium content in pool water to be in trace range below 50 μg/L. There are several routes to determine the uranium trace content in water in the literature; voltammetry has been systematically employed. In the present study, the chosen chemical determination of uranium traces used the voltammetric method known as AdCSV (adsorptive cathodic stripping voltammetry). This technique, based on mercury voltammetry, is an adequate methodology to determine uranium traces. The chloranilic acid [CAA] (2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone) is indicated as chelating agent. The redox reaction of 22 UO + with CAA is sensitive in the range of 2 < pH < 3. But pH variation imposes changing on [UO2(CAA)2] reduction potential. In this work, we present the uranium trace results for IEA-R1 reactor water, sampled after an operation routine shutdown. The uranium trace determination for IEA-R1 pool water showed content around 1 μg/L [U] with statistical significance. Therefore the IEA-R1-reactor-water purification showed to be adequate and safe.