Preconcentration and Determination of Traces of Strontium in Natural Waters by Ion-Exchange and Flame Atomic Absorption Spectrometry

A flame atomic-absorption spectrophotometric method for determining strontium in natural waters is described. The use of ethylenediamine tetraacetic acid (EDTA) to suppress interferences was studied, and ion-exchange with Amberlite IR-120 (H+) to concentrate the metal was used; strontium being eluted with 3% EDTA. The precision and reproducibility of the method were also investigated, and optimum results were obtained. Strontium concentrations for samples analyzed were between 4 and 147 μg/l. The detection limit was 1.6 μg/l, and the sensitivity was 3.2 μg/l for strontium.