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 dihydroxynitrobenzenes. 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.