Sorption technologies in modern applied radiochemistry
Keywords:
sorption, radionuclides, cesium, strontium, uranium, rare earth elements, transuranic elements, spent nuclear fuel, radioactive waste.Abstract
This paper represents a review of results obtained in the Laboratory for radioactive elements chromatography with the Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences (IPCE RAS) during the sorption material characterization studies in relation to different radionuclides. The studies showed the chelating resins with phosphonic groups to be the most efficient for the recovery of uranium from sulfate and carbonate solutions arisen in the uranium ore leaching process as well as for the separation of Th4+/UO22+, Pu4+/UO22+, Pu4+/Am3+ pairs of ions.
The sorption technology for the recovery of 137Cs from Purex process raffinates was developed using a potassium-copper ferrocyanide based inorganic sorbent. The application of the technology provided for the recovery of 137Cs from nitrate solutions of a complex composition in the repetitive sorptiondesorption-regeneration cycle mode. Studies of the Russian-manufactured tetraoctyldiglycolamide (TODGA) based sorbents demonstrated the high sorption capacity of those in relation to Eu3+, Th4+, and UO22+ ions within the wide range of the nitric acid concentration, and the sorbent characteristics to be highly competitive with foreign analogs. Investigation of the sorption-selective characteristics of inorganic sorbents of different type offered the possibility to develop a number of radioactive waste treatment technologies and successfully implement them at different enterprises of the Russian atomic industry.
