Removal of Dye and COD from Textile Wastewater Using AOP (UV/O3, UV/H2O2, O3/H2O2 and UV/H2O2/O3)

Introduction: Textile industry effluent is a complex sewage with chemical and color materials that is discharged into the environment and can cause serious problems. In this way using advanced oxidation methods and finding the best methods for removing color materials is necessary. An experimental method was done on Kashan textile industry effluent in laboratory scale and batch system. Material and Methods: Initially, optimal condition was obtained for O3 and H2O2 and followed by advanced oxidation methods (UV/O3, UV/H2O2, O3/H2O2 and UV/H2O2/O3) in different reaction times and pH on dye removal and COD (chemical oxygen demand) were determined. The results were compared with complex repetition method. Results: The results of this research showed that dye removal impact and COD based on the type of process and reaction time in UV/H2O2/O3 by 30 minute time duration, was the most effective method. UV/H2O2 in 10 minute time duration was the least effective method. COD and color removal, based on the process in UV/H2O2/O3 and pH = 6 was the most effective. The effect of UV/H2O2 and pH = 4 was the least efficient method on dye material removing. Results showed that the treatment time was effective on color removing (P < 0/001) statistically. Conclusion: It can be concluded that UV/H2O2/O3 was the most efficient on color removing process, compared to the others, due to co-incidence presence of strongly numerous oxidants and their aggravating effect through producing active hydroxyl radicals (OH˚).