Investigation of the kinetics of the micropollutant removal by using environmentallyfriendly wastewater treatment methods: Fenton like oxidation of Methylene Blue in the presence of LaFeO3 perovskite type of catalysts [Çevre dostu atiksu aritimi yöntemleri ile mikrokirletici giderimi kinetiginin incelenmesi: LaFeO3 perovskit tipi katalizör varliginda metilen mavisinin Fenton benzeri oksidasyonu]

Methylene Blue which has a wide usage area in various sectors including the medicine, pharmaceutics, chemistry and textile is one of the common pollutants found in industrial wastewaters. In this study, the catalytic performance of LaFeO3 perovskite type of catalyst under different reaction conditions in Fentonlike oxidation of the target micropollutant, Methylene Blue was compared. In the parametric study the initial H2O2 concentration was fixed at 1 ppm (1000 µg/L). The aromatic degradation and the decolorization efficiencies were evaluated as 74.5% and 94.6%, respectively, under the optimum reaction conditions which were determined as 0.05 g/L of catalyst loading, 3.5 of pH, 0.1 mM of the initial H2O2 concentration and 45°C. The iron leaching under the optimum conditions was 0.63 ppm. The toxicity tests were performed by the comparison of the Lepidium sativum root lengths growing in the treated dye solution and the distilled water. The toxicity was evaluated as 1.2% in terms of root growth inhibition. In the kinetic study a reaction mechanism was proposed and the reaction rate equation was derived. The decolorization reaction followed pseudo first order reaction kinetics. The activation energy and the pre-exponential factor were calculated as 130.8 kJ/mole and 1.2 ×1020 min-1, respectively.