Formation of an intermediate oxygen complex in autoxidation of Fe(II)-ethylenediamine tetraacetate

1. By the standing-jet method the authors have studied the kinetics of autoxidation of the ethylenediamine tetraacetate complex of Fe2+ in neutral and acid media. From the kinetic results they infer the formation of an intermediate oxygen complex which interacts either with H+ or with a second Fe2+ ion. 2. In the system Fe2+-EDTA-O2, in an acid medium O2 is reduced by a radical mechanism via intermediate formation of HO2; in a neutral medium, directly to H2O2. 3. The authors obtain quantitative estimates of the rate constants of formation and further reactions of the oxygenated complex in the absence of ligands and substrates.