Elimination of 2,4,6-trichlorophenol by UV radiation combined with H2O2

The decomposition of 2,4,6-Trichlorophenol aqueous solutions, an environmental pollutant mainly present in wastewaters from the pulp bleaching industries, has been conducted in a photochemical reactor by the Advanced Oxidation Process constituted by the combination of UV radiation and hydrogen peroxide. The operating variables temperature and hydrogen peroxide initial concentration have been modified and a positive influence of both variables on the global degradation process is observed. For the kinetic study, a reaction mechanism is proposed and a rate equation is deduced for this process. The application of the experimental data to that rate equation leads to the evaluation of the kinetic constants for the radical reaction between the organic compound and the hydroxyl radicals generated in the photodecomposition of the hydrogen peroxide. These kinetic constants are correlated as a function of the temperature by an Arrhenius-type expression.