Most heterogeneous catalysts available for catalytic ozonation are present as powders and not ideal for column operation in advanced water treatment. In this study, a mesoporous Ce-Ti-Zr ternary oxide (CTZO) millisphere of large size (0.8-1.0 mm in diameter) and high surface area (180 m² g^-1) was synthesized as a highly stable catalyst to meet the hydrodynamic demand in column ozonation. The fraction of Ce(III) is much higher on the surface of CTZO (49.2%) than CeO₂ (27.5%), resulting in its high catalytic activity in ozone decomposition and mineralization of oxalic acid (OA), an ozone-refractory probe compound. The most favorable catalytic ozonation of OA was observed at pH 3.0 and the adsorption of OA by CTZO via surface complexation is a requisite step for its ozonation. The EPR analysis and radical scavenging experiment confirmed that ·OH was the dominating reactive species in catalytic ozonation of OA by CTZO. XPS revealed that the oxidation of OA was mediated by the Ce(III)/Ce(IV) redox cycle, which continously accepts the electron supply from OA ligand and meanwhile donates electron to activate O₃ into ·OH. The catalytic ozonation of OA by CTZO was enhanced in the presence of sulfate due to the generation of sulfate radical. Cyclic runs demonstrated that the CTZO millispheres exhibited high stability for sustainable catalytic ozonation of OA without noticeable release of Ce or change of Ce valence state. This study will provide new insight for the development of efficient ozonation catalysts towards practical application in advanced water treatment.

大多数可用于催化臭氧化的非均相催化剂均以粉末形式存在，不适用于高级水处理中的色谱柱操作。在这项研究中，合成了大尺寸（直径0.8-1.0毫米）和高表面积（180 m ² g ^-1）的介孔Ce-Ti-Zr三元氧化物（CTZO）毫微米球，作为满足上述要求的催化剂。柱臭氧化中的水动力需求。在CTZO表面上，Ce（III）的比例比CeO ₂高得多（49.2％）（27.5％），使其在臭氧分解和难处理的探针化合物草酸（OA）的矿化中具有很高的催化活性。在pH为3.0时观察到最有利的OA催化臭氧化反应，CTZO通过表面络合吸附OA是其臭氧化反应的必要步骤。EPR分析和自由基清除实验证实，·OH是CTZO催化催化臭氧化OA的主要反应性物质。XPS揭示了OA的氧化是由Ce（III）/ Ce（IV）的氧化还原循环介导的，该循环连续接受OA配体的电子供应，同时提供电子以激活O ₃入·OH。在存在硫酸盐的情况下，由于硫酸根的产生，增强了CTZO对OA的催化臭氧氧化作用。循环运行表明，CTZO毫球对OA的可持续催化臭氧化反应显示出很高的稳定性，而没有明显的Ce释放或Ce价态变化。这项研究将为开发有效的臭氧化催化剂提供实际应用，以期在高级水处理中得到实际应用。