Determination of ²²⁸Ra in waters

The main point of this work was to separate and determine isotope of radium (Radium-228) in mineral waters from Slovakia and Czech republic by using of sorbent material of MnO₂-PAN. Mineral waters were spilled through the column which contained MnO₂-PAN. MnO₂-PAN is new type of sorbent: manganese dioxide is bounded on polyacrylonitrile (PAN). Radium (which was caught on this sorbent) was washed up using HCl (6 mol·dm^-3) and then solutions of HNO₃ and HCl were prepared for next separation on Ln Resin (with HNO₃: 0.095, 0.35 and 8 mol·dm^-3) and DGA Resin (with HCl: 2 and 5 mol·dm^-3). Ln Resin and DGA Resin were used for radiochemical separation of actinium (²²⁸Ac is a daughter product of ²²⁸Ra in thorium decay chain). Ba-133 was used as the radionuclide tracer and the measurement preparation was prepared by co-precipitation with CeF₃ and is controlled and measured by alpha spectrometry. (authors)