Plasma-Degradation of Dinitrophenols and Interpretation by the Molecular Orbital Theory

Abstract

The advanced oxidation of 2, 4 - dinitrophenol (DNP), 2, 5 - DNP, and 3, 4 - DNP in aqueous solution has been investigated using a multi-gas, dielectric barrier discharge, and the degradation was measured by high performance liquid chromatography (HPLC). The acceleration of the advanced-oxidation has been investigated by the combination of the anion exchange polymer. The degradation pathway was suggested involving a rapid detachment of the nitro group followed by a slow opening of the aromatic-ring. The hydroxyl radical and the excited hydroxyl anion are responsible for the primary attack of the DNP with the production of dihydroxy-nitrobenzenes. The attack of hydroxyl radical occurs at the benzene ring carbon activated by the presence of a phenolic OH group and a nitro group. The reaction is dominated by a pseudo-first order kinetic reaction. The degradation process is interpreted using Molecular Orbital Theory.