Evaluation of nZVI for the degradation of atrazine in heterogeneous Fenton-like systems at circumneutral pH

The requirement of acidification for the successful Fenton processes in water treatment has promoted search new strategies to work at pH close neutrality. With this objective, use nZVI been evaluated oxidative elimination 10 mg L?1 atrazine circumneutral with nZVI/UVA, nZVI/H2O2, and nZVI/H2O2/UVA systems. While UVA irradiation sole was ineffective degrading herbicide, addition H2O2 boosted up reaction, system attaining highest degradation rate. inhibition reaction upon tert-butanol as scavenger pointed out significant role hydroxyl radicals oxidation. characterization fresh spent samples, carried by XRD, SEM, TEM, nitrogen adsorption-desorption experiments, confirmed presence ferric oxidized compounds responsible heterogeneous photo-Fenton-like reactions. On basis products determined high performance liquid chromatography (HPLC), a scheme pathways ZVI/H2O2/UVA proposed which is mainly initiated alkylic oxidation rather than dechlorination. Finally, effect on rate constituent species analyzed different matrices (pure, supply, simulated secondary effluent real water). Considered individually, Cl?, SO42?, HCO3?, DOC, showed moderate inhibitory kinetics, but their combination could explain decrease efficiency detected compared less complex matrices.