Determination of Reactive Intermediates During Anodic Oxygen-transfer Reactions at Lead Dioxide

摘要

The anodic discharge of water to produce adsorbed hydroxyl free radicals (· OH) is considered to be a prerequisite to anodic O-transfer reactions at a PbO_2 electrode. In this work, a method was studied by means of high-performance liquid chromatography(HPLC) combined with electrochemical detection (ED) so as to investigate the production of hydroxyl free radicals (·OH) in the process of the anodic discharge of H_2O at a PbO_2 electrode. The voltammetric data obtained at the PbO_2 electrode for the oxidation of salicylic acid to sal-icylate hydroxylation products(DHBAs) and the detection of DHBAs by means of HPLC-ED confirm the proposed mechanism.