METHOD OF CONCENTRATING RADIUM RADIONUCLIDE FROM WATER Russian patent published in 2003 - IPC

FIELD: analytical methods. SUBSTANCE: invention relates to analytical chemistry of radioactive elements, in particular to methods for concentration and simultaneous isolation of radionuclides. Method can be used for isolating radionuclides from large volumes of water under natural conditions and consists in coprecipitation of barium and sodium chromates from great volume of water containing radium-226 and radium-228 and by adding saturated solutions of BaCl₂, K₂Cr₂O₇ and CH₃COONa. Chromate precipitate is filtered off, rinsed, dried, and calcined. Anhydrous sodium and potassium carbonates are the added to calcined precipitate and the total is melted in muffle kiln to achieve homogenous composition. To transfer radionuclides into solution, alloy is leached, filtered, washed, and dissolved in 5% HCl. EFFECT: enabled concentration of radium-226 and radium-228 in the form of chromates followed by isolation thereof and transfer into soluble state. 1 tbl