METHOD FOR THE COEXTRACTION OF ACTINIDES AND TECHNETIUM FROM AQUEOUS SOLUTIONS FOR RADIOLOGICAL MONITORING PURPOSES

Radionuclide concentrations in natural samples and their monitoring appear to be essential when it comes to the environmental safety assessment and the evaluation of the consequences inflicted by nuclear weapons testing, as well as accidents at nuclear power plants. However, large volumes of natural water samples require some additional concentration. To date, no method has been developed that could provide the coextraction of actinides and technetium from large volumes of natural waters. Model experiments were implemented to study simultaneous coprecipitation of actinides and ⁹⁹Tc with iron (II and III) hydroxides and their subsequent separation using chromatographic resins. A technique providing ⁹⁹Tc concentration and extraction was adjusted: the amount of Fe³⁺ was taken equal to 0.8 g/l, K₂S₂O₅ in a concentration of 4 g/l was selected as a reducing agent. A technique has been developed to coextract Am, Pu, U, and Tc from large-volume natural samples and to specify their concentrations with a yield of 40—70 %.

 

Keywords: actinides, technetium, coprecipitation, natural samples, radioecological monitoring, radioactive waste.

Rozhkova A. K., Kuzmenkova N. V., Sibirtsev A. M., Petrov V. G. Method for the Coextraction of Actinides and Technetium from Aqueous Solutions for Radiological Monitoring Purposes. Radioactive Waste, 2021, no. 4 (17), pp. 94—103. DOI: 10.25283/2587-9707-2021-4-94-103. (In Russian).