Catalytic ozonation of p-nitrophenol over mesoporous Mn–Co–Fe oxide

• Mesoporous composite metal oxides were prepared by a simple method.
• Mn–Co–Fe was highly effective for the mineralization of p-nitrophenol.
• The adsorption of intermediates played an important role in this catalytic process.
• Surface reactions involving adsorbed ozone and organic molecules were proposed.

Mesoporous composite metal oxides were prepared by an oxidation–precipitation method. The characterization studies indicated that the structure and surface property of the products could be controlled through simple manipulation of precursor composition. The activity of the synthesized catalysts for ozonation of p-nitrophenol (PNP) in aqueous solution was investigated. It was found that the negatively charged surface enhanced the adsorption and decomposition of ozone, but inhibited the adsorption of organic intermediates. This heterogeneous catalytic ozonation process should mainly follow a mechanism of surface reactions involving adsorbed ozone and organic molecules. Mn–Co–Fe exhibited the highest catalytic activity and stability for the mineralization of PNP due to its proper adsorption capacities for ozone and organic intermediates, which facilitated the surface reactions.

Mn–Co–Fe oxide exhibited excellent activity for the mineralization of p-nitrophenol with ozone. The reaction mechanism involved the adsorption and surface reactions of ozone and organic intermediates.Figure optionsDownload as PowerPoint slide