PHOTOCHEMICAL OXIDATION OF REACTIVE BLUE 19 DYE (RB19) INTEXTILE WASTEWATER BY UV/K2S20sPROCESS

In textile industry, advanced oxidation processes are used for degrading and removing color from dyebaths which allow wastewater reuse. In this study, photochemical oxidation processes (UV-AlK2SzOs,UV-C/KzSzOs) and chemical oxidation process (darklK2SzOs), were investigated in a laboratory scalephotoreactor for decolorization of the Reactive blue 19 (RB19) dye from synthetic textile wastewater. Theeffects of operating parameters such as potassium persulphate dosage, pH, reaction time and UV source,on decolorization have been evaluated. The results of direct chemical oxidation showed that 50% of thedye was been removed using K2S20 Sin dark condition after 5h reaction time and photochemical oxidationshowed that UV-C irradiation is more effective than UV-A for RB19 dye removal. The RB19 solutionwas completely decolorized under optimal potassium persulphate dosage of 5mmol/L and low-pressuremercury UV-C lamps (15w) in less than 30min. UV/KzSzOg experiments showed higher color removalperformance under acidic conditions (pH=3), and in this condition with 5mmollL of potassiumpersulphate, 78.5% COD has been removed after 311 irradiation time. The decolorization rate fitted topseudo-first order kinetics with respect of dye concentration. The reaction rate constants forphotochemical degradation of RB19 were 0,014 and 0.237 for UV-AlKzS20S and UV-C/K2SZOS processesrespectively.