Background: Due to the large volume of water consumed in textile industry and producing the colored wastewater containing non-biodegradable organic dyes, in the present study the interaction of hydrogen peroxide and nanophotocatalyst in the advanced oxidation process was investigated.
Methods: In this research, after synthesizing of nanophotocatalyst (ZnO:Ag:Nd) the effect of hydrogen peroxide on dye removal process, and its interaction with the catalyst was investigated. photocatalyst was characterize by  (FESEM) Field-emission Scanning Electron (EDS) Energy-dispersive X-ray spectroscopy (XRD) X-ray diffraction methods. Then, the effect of important operating parameters such as dye concentration (10-30 ppm), pH (3-9), The amount of photocatalyst (0.02-0.1g.L^-1) temperature (30-50°C), hydrogen peroxide concentration (F=2-11) was evaluated in AOPs process. Process modeling was done by using the response surface methodology.
Results: The results showed that by adding hydrogen peroxide to photocatalyst particles, the efficiency of decolorization was increased, but the addition of catalyst to the optimum amount of hydrogen peroxide reduced the efficiency of decolorization. Also, the optimum conditions for the removal of dye matter (pH=6.21) and the amount of photocatalyst 0.08g.L^-1, F=9was achieved. The results of the thermodynamic studies showed the endothermic reaction of the process, and process modeling indicated that the theoretical result were in accord with the experimental results.
Conclusion: Based on the results, combination of using catalysts and hydrogen peroxide is an effective technique for dye removal of aqueous solution.