Determination of anions after their concentration by directed crystallization of natural water

Low-temperature directed crystallization of natural water earlier applied b y us for analytical concentration of cationic and organic impurities, may b e used also for the concentration of anions. The distribution coefficients of various impurities in distilled water, irrespective of their nature, wer e found to be close to zero. In natural water these values are nonzero and depend on the degree of mineralization of the analyzed water. The use of ou r concentration method allows to decrease the detection limit in the determ ination of anionic impurities by a factor of 40 to 100.