In this study, the CuO/MgO composite was prepared by co-precipitation method, as-prepared samples were characterized by SEM, TEM, XRD and N2 adsorption/desorption isotherms. The removal of tartrazine from aqueous solution by CuO/MgO/H2O2/UV was investigated and compared to other systems with/without H2O2 and UV irradiation. The amount of dye removed was determined by measuring the concentration of the dye at its characteristic wavelengths by UV-Vis spectrophotometer. The removal efficiency observed was in the order: CuO/MgO/UV/H2O2>CuO/MgO/H2O2>CuO/MgO/UV>CuO/MgO>UV/H2O2>UV>H2O2. In addition, the pseudo-first order kinetic model was used for fitting the experimental data profiles in order to find the reaction rate constant. efficiency observed was in the order: CuO/MgO/UV/H2O2>CuO/MgO/H2O2>CuO/MgO/UV>CuO/MgO>UV/H2O2>UV>H2O2. The degradation of tartrazine in reaction systems was proposed. In addition the pseudo-first order kinetic model was used for fitting the experimental data profiles in order to find the reaction rate constant.
