Mechanism of decomposition of peracetic acid by manganese ions and diethylenetriaminepentaacetic acid (DTPA)

Abstract The decomposition mechanism of peracetic acid by free Mn 2+ ions and by Mn 2+ -diethylenetriaminepentaacetic acid complexes was studied by UV/Vis, electrospray ionization-time of flight-mass spectrometry (ESI-TOF-MS), electron spin resonance (ESR), and Raman spectroscopy. The experimental results demonstrate that a number of different oxidation states of manganese are involved in the decomposition reaction. Furthermore, the kinetics observed show oscillatory features that are characteristic of autocatalytic processes. Radical pathways were found to play a negligible role in the reaction. Based on the experimental observations, an overall reaction scheme for the decomposition process is proposed.