Atomic absorption method for determination of antimony in aqueous solutions

Abstract

Due to the very different sources of polluted water, the estimation of a great number of constituents which are present in a large concentration range implies the development of suitable analysis methods, adapted to every type of matrix. In the present paper we worked out and validated in house an analytical method for the quantitative analysis of antimony in aqueous solutions, using on atomic absorption spectrometry – hydride technique. The described method is based on atomic absorption spectrometry of antimony resulted from the breakdown of antimony hydride. In the conditions used, only Sb (III) reacts with sodium borohydride to form antimony hydride. Due to this fact, prior to hydride treatment, antimony solutions are reduced to Sb (III). The reaction of Sb (III) with NaBH4 takes place in HCl solutions. Antimony is quantitatively estimated at λ = 217.6 nm, with a linearity range between 1 µg/L and 5 µg/L. The developed method’s accuracy is 103.3 %, the precision 2.49% and the repeatability 0.22 µg/L. The determined LoD is 0.127 µg/L and the limit of quantification (LoQ) 0.425 µg/L.