RAPID RADIOCHEMICAL SEPARATION AND DETERMINATION OF CHLORINE, BROMINE AND IODINE IN WATER SAMPLES USING ION-EXCHANGE

On the basis of tracer experiments, a simple and rapid radiochemical separation method for simultaneous determination of I-, Br- and Cl- in one aliquot of a water sample (only 2 - 4 ml) has been developed. The method is based on short irradiation of the water sample and separation of the halogens using sequential ion exchange columns filled with Dowex 1 x 8, 100 - 200 mesh anionic resin prepared in I-/I2, Br-/Br2 and Cl- form. After washing the columns with an appropriate volume of 2% NaCl solution, the resins were transferred to vials and activities of the isolated radionuclides I-128, Br-82 and Cl-38 measured together with standards in a "well type" or on a coaxial Ge detector connected to a Canberra 90 multichannel analyzer. Besides high chemical yields, from the gamma-spectra of the isolated radionuclides, it is evident that high decontamination factors are achieved. In this way water samples containing different amounts of total dissolved solids (distilled, drinking, mineral, river, sea water) were analyzed. Because of the lack of suitable reference materials for water analysis, the reliability of the results obtained was checked by titrimetric, extraction and ion chromatographic methods.