Firstly, Nano ceria with cubic lattice was prepared and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) techniques. Degradation kinetics of Acid Orange 7 (AO7) was investigated to understand the catalytic oxidation mechanism of the CeO2 with H2O2. The degradation of AO7 relies significantly on its adsorption on the surface of CeO2 with an apparent order of 2.40. Increasing the concentration of H2O2 increases the degradation reaction rate constant of AO7 in a positive line...