The photooxidative destruction of C.I. Basic Yellow 2 using UV/S2O82− process in a rectangular continuous photoreactor

The photooxidative decolorization of C.I. Basic Yellow 2 (BY2), was investigated using UV radiation in the presence of peroxydisulfate (S2O82−) in a rectangular photoreactor at experimental condition. S2O82− and UV-light showed negligible effect when they were used independently. Removal efficiency of BY2 was sensitive to the operational parameters such as initial concentrations of S2O82−, BY2, light intensity, flow rate and pH. The conversion ratios of BY2 at the volumetric flow rates of 330, 500 and 650 ml/min were 84%, 79%, 51% in 30 min, respectively. Our results showed that light intensity was a beneficial parameter for dye removal. The results showed that in the presence of S2O82−, the photooxidation quantum yield obtained was higher than direct photolysis quantum yield, suggesting that photodecay of BY2 was dominated by photooxidation. The electrical energy per order (EEO) values for decolorization of BY2 solution was calculated. Results show that applying a desired peroxydisulfate concentration can reduce the EEO.