Advanced oxidation processes are powerful techniques especially for the treatment of organic pollutants. Electro-Fenton (EF), one of the advanced oxidation methods, is electrochemical version of the Fenton process. In the EF process, electrooxidation and electro coagulation are combined to increase the degradability of organic compounds present in wastewaters. Electro-Fenton process has two different configurations. In the first one, Fenton reagents are added to the reactor from outside and inert electrodes with high catalytic activity are used as anode material while in the second configuration, only hydrogen peroxide is added from outside and Fe2+ is provided from sacrificial iron anodes. In this study, iron electrodes with an active surface area of 60 cm2 were used in the experiments. The distance between the electrodes was 1 cm. The removal of an azo textile dye (Deep Red, CI 12350) by EF method was studied under different experimental conditions. Na₂SO₄ was used as the supporting electrolyte. For this purpose, applied potential (5 to 12.5 V), pH (2 to 5) and H2O2 concentration (25 to 100 mM) was changed while keeping the dye concentration constant (100 mg/L), and their effects were examined on dye removal efficiency and energy consumption. Optimum values of parameters were pH of 3; applied potential of 5 V; H2O2 concentration of 25 mM. For these conditions, the energy consumption after 25 minutes was 2.43 Wh / L and dye removal 99.5%.
Anahtar Kelimeler: Deep red, electro-Fenton, advanced oxidation method.
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