Degradation of Dye Wastewater by Advanced Oxidation Process: A Comparative Study
The degradation of Rhodamine B (RhB) in water was investigated in laboratory-scale experiments, using five advanced oxidation processes (AOPs): UV/H2O2, fenton, photo-fenton, UV/TiO2, UV/TiO2/H2O2. The photodegradation experiments were carried out in a fluidized bed photoreactor equipped with an immersed 32 W UV-C lamp as light source. Initial decolorization rate and COD removal efficiency were evaluated and compared. The results obtained showed that the initial decolorization rate constant was quite different for each oxidation process. The relative order of decolorization was: photo-fenton > UV/TiO2/H2O2 > fenton > UV/H2O2 > UV/TiO2 > UV > H2O2. The relative order of COD removal was different from decolorization: photo-fenton ≒ UV/TiO2/H2O2 > UV/TiO2 > fenton > UV/H2O2. The photo-fenton and UV/TiO2/H2O2 processes seem to be appropriate for decolorization and COD removal of dye wastewater.