Diatomite supported MnOx-CoOx catalysts were successfully prepared by the incipient impregnation method, their activities were investigated through catalytic ozonation of nitroaromatic compounds (NACs) by simultaneously using them with ozone. Five factors three levels orthogonal testing method was used to optimize the preparation conditions of the catalysts, and the prepared catalysts were characterized by SEM,XRD, FT-IR and XPS, respectively. Results show that the effects of molar ratio of active components,calcination temperature and time are significant. At the same time, FT-IR analysis indicates that the catalytic metals supported mainly exist as multivalent mixtures and the abundant surface hydroxyl leads to high dispersion of MnOx-CoOx. Combination of XRD and XPS analyses indicate that the supported catalytic metals present on the catalyst surface with forms of well dispersed divalent, trivalent and tetravalent oxides. The catalyst could significantly enhance the mineralization level of NACs through catalyzing the decomposition of aqueous ozone into more hydroxyl radicals; the highest increment of TOC removal ratio is in the range of 35％～57％ compared with the TOC removal ratio of ozonation without associated with catalyst, which indicates that MnOx-CoOx/diatomite is a kind of heterogeneous catalytic ozonation catalyst with high activity.%以硅藻土为载体,成功制备了锰氧化物(MnOx)和钴氧化物(CoOx)复合金属催化剂,研究了其对硝基芳烃化合物臭氧氧化的催化活性.实验采用5因素3水平的正交实验方法优化了催化剂的制备条件,发现活性组分摩尔比、焙烧温度和焙烧时间对催化剂的催化性能影响显著.与单独臭氧化体系相比,催化剂投加体系TOC(总有机碳)去除率增幅达35%～57%,表明所制备MnOx-CoOx/硅藻土是一种高活性非均相臭氧氧化催化剂.应用XRD和XPS对催化剂结构进行了结构表征,负载金属以多价态氧化物形式分布于催化剂表面;FT-IR分析进一步揭示,催化剂富含表面羟基,推测制备的催化剂能够催化液相臭氧分解生成更多的羟基自由基(·OH),进而提高臭氧化效率以及硝基芳烃化合物的矿化水平.
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