Direct Poly Azo Dye Decolorization Using Nanophotocatalytic UV/NiO Process

In this study, efficiency of UV/NiO system as a forms of Advanced Oxidation Processes (AOP) to remove red poly azo was investigated. This study was conducted as a pilot scale and batch mode. Ultraviolet was achieved by 11 W low pressure lamp. Effects of various factors such as pH, different times of irradiation, different concentration of nickel oxide, primary concentration of colors were evaluated. The test results of UV/NiO system showed that no effects were observed with UV alone in photocatalysis process for removal of dye DR 80. Nickel oxide is an effective catalyst in removal of dye by the nanophotocatalytic process. The results represent that the color removal efficiency increase with pH reduction and optimum pH was found 4. Fainally, the highest removal efficiency for DR 80 dye with concenteration of 25 mg/L and 50 mg/L was obtained about 94.29% and 82.22% by the process of UV/NiO respectively. Reaction kinetic in the UV/NiO process follows pseudo secondry-order reactions. Totally UV/NiO process is an effective methode for DR 80 poly azo dye removal in aqueous solutions.