Chemical Engineering, Arak University
The application of synthetic colors in textile industries and their entry into the water and groundwater is an environmental problem because of being very toxic material. The synthetic colors which are used in textile dyeing (plyacrilic and polyester) are usually dispersing colorants. They derive the azo and anthraquinone chemicals. Electro-Fenton process is an efficient technique which can degrade the recalcitrant wastewaters. The main goal of the present study was to examine the effect of iron electrodes (as a cheap and available material) on industrial textile wastewater treatment by electro-Fenton technique. The experiments were conducted to evaluate the effects of reaction time, current density, pH, H2O2/Fe2+ molar ratio and volume ratio of H2O2 to textile wastewater (TW) (ml/l) on the process. Response surface methodology (RSM) was used to consider the effects of five independent variables on the COD and color removal from the wastewater and optimize the operating conditions. The optimum conditions were obtained at reaction time of 71.74 min, current density of 40.11 mA/cm2, pH 2.84, H2O2/TW of 2.03 (ml/l), H2O2/Fe2+ molar ratio of 3.89 for COD removal of 76.33%. Furthermore, optimum conditions were found at reaction time of 75.97 min, current density of 67.04 mA/cm2, pH 2.98, H2O2/TW of 1.69 (ml/l), H2O2/Fe2+ molar ratio of 2.98 for color removal of 79.33%.