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Composite sorbents based on nanoparticles of NiO, NiO-TiO2 and ZrO2-TiO2 were chosen for treatment of spent decontamination solutions based on citric acid. Active oxidic materials were prepared by photoinduced synthesis (NiO, NiO-TiO2) or hydrolytic method (ZrO2-TiO2). Weight distribution ratios for radionuclides 241Am, 60Co, 137Cs a 90Sr/90Y and others were investigated in the course of the experiments performed in pH range 2–12. High sorption capacities up to 9 mmol∙g-1 for 137Cs were found by sorption isotherm experiments. Dynamic experiments were performed with simulated spent decontamination solutions based on citric acid. Elution of radionuclides was tested with mineral acids (HCl, HNO3, HClO4) or complexing agents (citric acid, Na3NTA, HEDP). Under suitable conditions, 85 % of radionuclide was eluted in 6times lower volume compared to treated spent solution. Bleeding of Ni ions from active components was detected during half-scale test due to ICP-MS analysis.