Catalytic Ozonation of Oxalic Acid in the Presence of Fe₂O₃-Loaded Activated Carbon

ABSTRACT

The activity and optimum condition of metal-loaded activated carbon catalyst (Me/AC) for oxalic acid (OA) ozonation were evaluated. Results showed that Fe-loaded activated carbon (Fe/AC) showed better activity in five kinds of Me/AC catalysts prepared by a dipping method. Fe catalyst, crystallizing as γ-Fe₂O₃, dispersed well on AC surface. Fe₂O₃/AC, with 1.12% Fe weight ratio and 450°C calcination temperature and showed better activity for OA ozonation. 89.2% of OA was removed in the Fe₂O₃/AC/O₃ process, which was higher than those in AC/O₃ (79.6%) and O₃ (3.2%) processes. The calcination process helped to promote adsorption capability and catalytic activity of AC. In addition, Surface hydroxyl groups played a key role in Fe₂O₃/AC’s catalytic activity. Acidic condition was more favorable for OA removal in the Fe₂O₃/AC/O₃ process. A hydroxyl radical (•OH) oxidation mechanism was proven in Fe₂O₃/AC/O₃. The catalytic activity of Fe₂O₃/AC remained satisfactory after several cycles, indicating that Fe₂O₃/AC had a good reusability property.

KEYWORDS:

• Activated Carbon
• Catalytic Ozonation
• Fe₂o₃
• Oxalic Acid
• Ozone

Acknowledgments

The authors are particularly grateful for the financial support from the National Science and Technology Major Projects (No. 2012ZX07206003), the Science and Technology Program of Guangzhou (No. 201607010276) and the Innovation Project of Graduate School of South China Normal University.

Additional information

Funding

This work was supported by the Science and Technology Program of Guangzhou [No. 201607010276]; Innovation Project of Graduate School of South China Normal University; and National Science and Technology Major Projects [No. 2012ZX07206003].