Spectrophotometric method for the determination of chlorite and chlorate

Abstract

The concentrations of aqueous chlorite and chlorate in mixtures can be determined by the decolorization of Indigo Carmine at 610 nm in the presence of Fe^II. The reactions are stoichiometric and therefore a good correlation between the absorbance and the concentration is found. The linear range for measurements of chlorite is 0–0.51 mg l^–1 and that of chlorate is 0–0.78 mg l^–1. The detection limits for chlorite and chlorate are 0.036 and 0.008 mg l^–1, respectively. The presence of chlorine interferes with the determinations.