Treatment of spent decontamination solutions based on citric acid with composite polyacrylonitrile: transient metal oxidic nanoparticles sorbents

Composite sorbents based on the nanoparticles of NiO, NiO-TiO2 and ZrO2-TiO2 embedded in polyacrylonitrile were chosen for the 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 Am-241, Co-60, Cs-137 and Sr-90/Y-90 Y were investigated during the experiments performed in pH range 2-12. High sorption capaci- ties up to 9 mmol g(-1) for Cs-137 were found by sorption isotherm experiments. Dynamic experiments were carried out with simulated spent decontamination solutions containing citric acid. Elution of > 85% radionuclide waste with mineral acids or complexing agents was in 5-6 times lower volume compared to treated spent solution.