Nanoparticles of metal oxides with high specific surface area show high adsorption towards selected radionuclides with fast kinetics. Metallic nanooxides were tested for separation of selected radionuclides (Am-241, Co-60, Cs-137, Sr-90) from simulated spent decontamination solutions containing citric acid. Following materials, prepared by photoinduced synthesis, were tested: NiO, NiO/TiO2 and ZnO:Cu. Buffer solutions with concentration of citric anions 0.01 mol/L were tested. Sorption properties (sorption kinetics and weight distribution ratios) were investigated in the course of the experiments performed in pH range 2–12. Additionally, the influence of the presence of surfactants on the sorption was studied. The results obtained show that metal oxides in the form of nanoparticles adsorb radionuclides rather in the basic pH range. Outcomes will be used for the development of method for in situ treatment of spent decontamination solutions containing citric acid produced during radiation accident.