Synthesis and Characterization of Activated Carbon Photocatalyst Modified with ZnO/SnO2 Nanoparticles and Its Application in the Municipal Wastewater Treatment with Advanced Oxidation Process

Due to the increase in population and industrial activities, the demand for clean water has increased. On the other hand, the amount of fresh water has decreased; As a result, wastewater treatment, including municipal and industrial wastewater, has become very necessary. One of the wastewater treatment methods is the Advanced Oxidation Process (AOP). This research used the advanced oxidation process using the photo-catalyst based on modified activated carbon to treat municipal wastewater in Yasouj City. Activated carbon was prepared from the walnut shell using the chemical activation method and then modified by a composite of ZnO and SnO2 nanoparticles and used as a photo-catalyst in the designed reactor for wastewater treatment. The results of FTIR, XRD, and EDX analyses confirmed the presence of ZnO/SnO2 nanoparticles on the modified activated carbon surface. Due to the coating of these nanoparticles on the surface of the activated carbon and inside its pores, the specific surface area of the modified activated carbon is greatly reduced compared to the activated carbon. The results of the DRS analysis show the low band gap of the synthesized photocatalyst and its applicability in the presence of visible light. To optimize the effect of the parameters, the central composite design method was used to design the experiment. The results showed that the maximum amount of COD reduction of 97.41% has been achieved at a pH of 3, the amount of photocatalyst of 1.25 g/L, and the duration of light irradiation of 45 minutes.