Heterogeneous kinetic study of Ce-Ag-ZnO nano-photocatalyst for degradation of reactive red (RR120) dyes

In this study, ZnO nano-photocatalyst modified with different mass ratios of Ag and Ce metals was synthesized by combustion, and microwave methods. According to the results of bleaching experiments, it was determined that the catalyst synthesized with a mass ratio of Ce/Ag equal to 0.5 was more efficient, so the properties of this catalyst were evaluated by XRD, FT-IR, SEM, and PL analyses. The ability of Ce-Ag-ZnO was investigated by the photodegradation of Reactive Red 120 (RR120) dye in a semi-continuous reactor at dissimilar pH, catalyst amounts, and dye concentrations. The experiments showed that the optimal conditions for dye decolorization were for 20 mg L⁻¹ of dye concentration, pH= 7, and 0.1gL⁻¹ of catalyst, and under these conditions the efficiency is obtained above 99 %. By following a pseudo-first-order equation, kinetic studies of the synthesized photocatalyst showed economic calculations. Also, the experimental design was carried out using the RSM method and the CCD model in Minitab16. It was determined that the experimental data values, and those calculated through the model are in good agreement with literature data.