3.5 Radium-Barium separation
The purification of the dissolved Ra is necessary for radiochemical analysis and best benefit of
waste treatment, where the main obstacle is the Ra-Ba separation. Several studies cited the Ra-Ba
separation from their water-soluble salts, especially from nitrate and chloride forms
(Beklemishev et al., 1994; Chiarizia et al., 1999; Kabai et al., 2014). In this work, Ra-Ba
separation was investigated using precipitation and ion exchange methods. After dissolution of
[226Ra]BaSO4 using the proposed method in HCl solution, a new precipitate of Ra and Ba
chloride was formed due to the high concentration of the acid. The difference in the RaCl2 and
BaCl2 solubility in acid-ethanol mixture was found to be useful in the Ra-Ba separation.
Therefore, the ion exchange separation was carried out in two cases, 1) directly after the
[226Ra]BaSO4 dissolution, 2) after Ra-Ba separation using the precipitation method in acidethanol
mixture. Table 4 presents the ion exchange efficiency in 226Ra purification at two levels
of Ba concentrations. The observations show that the dissolved 226Ra from [226Ra]BaSO4 can be
efficiently removed and purified over ion exchange resins, especially after Ra-Ba separation in
acid-ethanol mixture. This can be of great importance in the development of radiochemical
analysis of Ra isotopes.