The Autocatalytic Oxidation of Iodine with Hydrogen Peroxide in Relation to the Bray-Liebhafsky Oscillatory Reaction

Abstract

The oxidation of iodine with hydrogen peroxide was studied spectrophotometrically and potentiometrically. At low concentrations of HClO4, after induction period (IP), the iodine concentration decreases sigmoidally and IP decreases with decreasing surface area of the solution interphase. We assume that •OH radicals are produced via the oxidation of iodide with H2O2 and, by their subsequent reaction with H2O2, the HO2• radicals are formed. By their disproportionation, 2 HO2•  ↔   H2O2 + 1O2, very reactive singlet oxygen is produced and the oxidation of iodine can start. The described experimental results are consistent with the Noyes-Treindl mechanism.