A High Photo-Catalytic Activity of Magnetic Composite Based on Chitosan and Manganese-Doped Zinc Oxide Nanoparticles for Removal of Dyeing Wastewater

In this study, a novel high photo-catalytic activity of magnetic composite based on chitosan and manganese-doped zinc oxide nanoparticles (Mn–ZnO/Fe₃O₄/CS) was synthesized using a combination of sol–gel and co-precipitation methods. The results showed the role of manganese in improvement of photo-catalytic activity of Mn-doped ZnO/Fe₃O₄/CS compared with ZnO/Fe₃O₄/CS. Physical properties and characterization of prepared material were investigated by FT-IR, SEM, VSM, XRD and TGA. The photo-catalytic activity of composite was performed on the reactive blue 198 dye (RB198). Various parameters (pH, initial concentration, illumination time, dosage of material) effecting photo-catalytic activities were also examined. Moreover, the composite was applied for real dyeing wastewater with high efficiency. Excitingly, the COD results indicated that the photocatalytic activity of Mn-doped ZnO/Fe₃O₄/CS composite improved with representation of manganese doped into structure of magnetic composite. Finally, the reusability of the material was still remained with high discoloration efficiency after 4 times of treatment with dyes.