Heterogeneous Catalytic Ozonation for Water Treatment: Preparation and Application of Catalyst

ABSTRACT Catalytic ozonation including homogeneous and heterogeneous ozonation has been extensively used in water and wastewater treatment in recent years. The liquid homogeneous catalysts cause secondary pollution and have limited development prospects. The heterogeneous catalyst exists in solid form, which is easy to separate solid from liquid, convenient to operate, and has high catalytic ozone decomposition efficiency. It can effectively mineralize organic pollutants and has great development potential. The catalyst is the core part of the whole method. In this study, the mechanism of heterogeneous catalytic ozone oxidation is briefly introduced. Several common preparation methods of ozone catalysts are reviewed. Various catalytic ozonation catalysts such as metal oxides, metals/metal oxides on supports, and carbon-based materials are summarized in detail. The application of heterogeneous catalytic ozonation in the degradation of phenols, pesticides, dyes, drugs, and other toxic organic pollutants is reviewed. At present, the structure of the catalyst is unstable, the active components of the catalyst are easily lost, and the catalytic effect is lost. Therefore, the development of supported catalysts with good stability has become the main direction of current research. The preparation and application of heterogeneous catalytic oxidation are also reviewed, which will be beneficial to further research.