Development of a Tandem Generator System ~(229)Th/~(225)Ac/~(213)Bi for Repeated Production of Short-Lived alpha-Emitting Radionuclides

摘要

~(229)Th was isolated from a long-stored ~(233)U sample using an anion exchanger and 8 M HCl. Thorium was separated from macroamounts of inactive impurities on an anion exchanger in aqueous-methanol HNO_(3) solutions. A tandem generator system was developed for repeated isolation of ~(225)Ac (alpha, 10 days) from the parent radionuclide ~(229)Th (7.3 X 10~(3) years) sorbed on an anion-exchange column, with the subsequent sorption of Ac on a cation-exchange column and repeated elution of ~(213)Bi (alpha, 45.6 min) with dilute HCl and HBr solutions. The gamma-ray spectra of the radionuclides at various steps of their isolation are presented. Alternative procedures for production and isolation of ~(225)Ac and ~(213)Bi are described. The application potential and advantages of the newly developed tandem generator system are discussed.