RESUMEN
The operation of nuclear power plants generates large quantities of radioactive materials or waste, which need to be characterised before decommissioning or for final disposal in radioactive waste repositories. The nuclear operators in Slovakia must declare 19 critical radionuclides in all radioactive waste before storage in the regional waste repository. This article describes a simple and rapid method for the determination of one critical radionuclide, 79Se, in radioactive waste. The conditions for the effective distillation of selenium from various mixtures of HCl and HBr solutions were studied. The highest selenium recoveries were achieved in a mixture of 6.5â¯molâ¯L-1 HCl and 18.3â¯molâ¯L-1 HBr in 7:1â¯vol ratio. The method was applied for the determination of 79Se in radioactive concentrates and sludge samples from nuclear power plants in Slovakia. 79Se was measured with a TRI CARB 3100â¯TR liquid scintillation counter.
RESUMEN
This paper describes a method employing anion exchange resin for determination of 126Sn in radioactive waste. The method is suitable for the separation of 126Sn isotope from hydrochloric and hydrofluoric acid solution. The separation is based on precipitation of tin with ammonium sulfide in 0.5molL-1 HCl, dissolution of the precipitate in concentrated HCl, loading in 2molL-1 HCl onto anion exchange resin column and elution with 2molL-1 HNO3. 126Sn was measured by gamma spectrometry.