The purpose of the study: on the basis of information analysis of modern approaches and experimental studies, to develop effective methods of decontamination of radioactively contaminated waters of the Chernobyl Exclusion Zone.

Research materials and methods. The object of our research was liquid radioactive waste stored in the sumps of one of the decontamination points for equipment and vehicles (PuSO) - the "Dibrova" facility. Modern research methods are applied - scanning electron microscopy, X-ray diffractometry, laser sedimentography. The mass fraction of cesium, strontium, cobalt, and manganese was determined by the atomic absorption method using an AA-8500 atomic absorption spectrophotometer (Nippon Jarrell Ash Co Ltd, Japan).

The results. The effectiveness of the proposed sorbents based on nickel-potassium ferrocyanide-modified iron oxide micro- and nanotubes and iron (III) hydroxide nanoparticles, the size of which is mainly 1-100 μm, is shown. The choice of decontamination algorithm depends on the composition of liquid radioactive waste to be cleaned. To increase the degree of strontium extraction while maintaining the high efficiency of cesium and transition metal extraction, it is advisable to apply preliminary plasma chemical treatment followed by the use of sorbents based on iron oxides/hydroxides modified by ferrocyanides.

Conclusions. The possibility and expediency of using the proposed method for the decontamination of liquid radioactive waste accumulated in the Chernobyl exclusion zone and for the current control of the condition of the storage sites of accumulated radioactive waste and radiation monitoring are shown.

liquid radioactive waste, Chernobyl exclusion zone, sorption method, ferrocyanides, iron oxides/hydroxides, medical consequences of the Chernobyl NPP accident

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