Kinetic and mechanism of TNT degradation by UV-VIS photocatalysis on iron doped TiO2

Abstract

"2,4,6-Trinitrotoluene(TNT) is one of most common toxic pollutant identified in wastewater generated from ammunitions plants, due to its potential carcinogenic characteristics. Various treatment methods were investigated in order to remove such toxic pollutants and among them, photocatalysis was successfully applied. From various semiconductors, titanium was a widely studied photocatalyst, due to its chemical inertness, low cost, photo stability and nontoxic character. Since, TiO2 is only photoactive under UV irradiation, modification of semiconductor by metal doping, aimed to reduce photocatalyst band gape and increase its quantum efficiency in visible domain represents an important issue. Fe-TiO2 assisted photocatalytic degradation of TNT in aqueous media, under UV-VIS irradiation was studied. The effects of operating parameters such as catalyst loading and pollutant concentration were assessed. TNT degradation was found to follow a pseudo-first order kinetic. The main oxidative species responsible for pollutant degradation are the surface adsorbed hydroxyl radicals."