1994 Volume 10 Issue 1 Pages 35-38
We propose a simple colorimetric method for determining chlorine dioxide in water in the presence of hypochlorite and/or chlorite. This method is based on the coloration of an m-aminobenzyl alcohol (ABA). The reagent solution changes from colorless to red-violet in the presence of chlorine dioxide. Since the red-violet coloration is proportional to the concentration of chlorine dioxide, this concentration can be determined by comparing it to a color standard of chloranilic acid. When ABA and chlorine dioxide react for 10min at pH 2-7, the detection limit of the chlorine dioxide is 0.1ppm. The maximum absorption wavelength of the reaction product of ABA and chlorine dioxide is 532nm. This product was separated by column chromatography, and the structure (C7H5O3Cl) was then determined by ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR), and mass (MS) analyses.
