Kinetics analysis of photocatalytic degradation of Acid Orange 7 by Co/N/Er3+: Y3Al5O12/TiO2 films

Abstract To improve the efficiency of decomposition of dye wastewater, the experiments of sonocatalytic degradation of Acid Orange 7 by TiO2-based films with doping Co, N and Er3+: Y3Al5O12 were performed in this paper. Based on analysis of the change of concentrations of the samples over time, the result showed that sonocatalytic degradation of Acid Orange 7 by TiO2-based films agreed with the pseudo-first-order kinetics. The effect of doping mass fraction of Er3+:Y3Al5O12, Co and N inTiO2-based films and reaction temperature on degradation rates were studied. The optimal doping mass fraction of Er3+: Y3Al5O12, Co and N were 1.81 %, 2.01 %, and 12.03 % respectively at 20 °C. The model of the reaction rate constants of sonocatalytic degradation of Acid Orange 7 by Co/N/Er3+: Y3Al5O12/TiO2 films were fitted. The errors between the model values and the experimental results were all less than 15 %. So the models could be used to estimate the degradation rate and concentration of Acid Orange 7 and provide theoretical basis for the design of catalytic reaction.