Oxidation of atrazine in aqueous media by solar- enhanced Fenton-like process involving persulfate and ferrous ion

Abstract

The oxidation of s-triazines (using atrazine (ATZ) as a model compound) by a solar-enhanced Fenton-like process involving persulfate and ferrous ion was studied. A flow-through tubular photoreactor was employed for the experiments. The solar-enhanced oxidative system involving ferrous ion and persulfate (Solar/S2O82−/Fe2+) showed the highest ATZ degradation efficiency when compared with other treatments (unactivated S2O82−, Solar - sunlight only, S2O82−/Fe2+, Solar/S2O82−). Complete degradation of ATZ and 20% reduction in total organic carbon (TOC) content were observed after 30min of the treatment. The in situ generated •ОН and SO4–• radicals were shown to be involved in ATZ oxidation using the radical scavengers methanol and tert-butyl alcohol. Furthermore, iron compounds were shown to act not only as catalysts but also as photo-sensitizers, as the introduction of ferrous ion into the reaction mixture led to an increased absorbance of the solution and expansion of the absorption spectrum into the longer wavelength spectral region.