The oxidative degradation of Orange G dye by nanosized CeO2 catalyst has been performed in this study. The catalyst was prepared by precipitation method. Various characterization techniques were carried out to study the physical and chemical properties of the synthesized catalyst. The XRD result confirms well the formation of CeO2 cubic phase. The FTIR result showed the effect of calcination temperature for CeO2 was clearly observed due to reduction in band intensity compared to uncalcined Ce nitrate sample. Meanwhile, the diffused reflection spectra recorded reflection spectra at 414 nm with an energy gap of 3.2 ev. The decolorization of Orange G dye by oxidation process were carried out under various conditions such as, the effects of H2O2 dosage , pH, catalyst dosage and the temperature of reaction. The optimum conditions for the highest decolorization efficiency (100%) were achieved at 10 mg/L of orange G dye with catalyst dosage of 1.5 g/L, pH 2, reaction temperature of 65 °C and 0.1 mL H2O2.
