Determination of iodide in table salt by flow injection analysis using Pyrocatechol Violet

Abstract

A spectrophotometric flow injection method for the determination of iodide based on the catalytic effect of this ion on the oxidation of Pyrocatechol Violet by potassium persulphate was developed. The method allows the determination of 0.5–5 mg litre −1 iodide at a rate of 60 samples per hour and is subject to very few interferences. It was successfully applied to the determination of iodide in table salt.