Ngày nhận bài: 23-01-2017 / Ngày duyệt đăng: 27-04-2017 / Ngày xuất bản: 06-08-2025
In this study, MnO2/Al2O3 catalysts were synthesized from manganese acetate and aluminum hydroxide by the sol-gel method at room temperature, followed by thermal treatment at 300°C. The characterization of the product was performed by X-ray diffraction (XRD), energy dispersive analysis of X-rays (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET). The ozonation of methylene blue (MB) solution in the presence of MnO2/Al2O3 catalyst was investigated in a laboratory scale batch reactor. The effect of pH solution (2-12), reaction time (0 - 60 minutes), and MnO2/Al2O3 catalyst dosage (0 and 0.1 - 5 g.L-1) on MB treatment was determined. The results showed that the reaction with the presence of catalyst required less time and improved the reduction level of MB compared to conventional ozonation. The optimal pH and catalyst dosage values were 8 and 1 g.L-1, respectively. For textile dyeing wastewater treatment, the catalytic ozonation decreased the color scale from 7693.89 Pt-Co to 28.40 Pt-Co and COD from 387.60 mg.L-1 to 52.35 g.L-1. Therefore, the ozonation with MnO2/Al2O3 catalysts can be considered as effective and feasible for treating the textile dyeing wastewater.
