School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
School of Energy and Power Engineering, Beihang University, Beijing 100191, China.
Environ Sci Technol. 2024 Aug 13;58(32):14329-14337. doi: 10.1021/acs.est.4c02050. Epub 2024 Aug 1.
A series of Mn and Fe metal oxide catalysts loaded onto USY, as well as single metal oxides, were prepared and characterized. The effects of interactions between the catalytic components and the introduction of gas phase NO on the catalytic ozonation of toluene were investigated. Characterization showed that there existed strong interactions between MnO, FeO, and USY, which enhanced the content of oxygen vacancies and acid sites of the catalysts and thus boosted the generation of reactive oxygen species and the adsorption of toluene. The MnFeO-USY catalyst with MnO and FeO dimetallic oxides exhibited the most excellent performance of catalytic ozonation of toluene. On the other hand, the presence of NO in reaction gas mixtures significantly promoted both toluene conversion and mineralization, which was attributed to the formation of nitrate species on the catalysts surface and thus the increase of both acid sites and toluene oxidation sites. Meanwhile, the reaction mechanism between O and CH was modified in which the strong interactions between MnO, FeO, and USY accelerated the reaction progress based on the L-H route. In addition, the formation of the surface nitrate species not only promoted reaction progress following the L-H route but also resulted in the occurrence of the reaction via the E-R route.
一系列负载在 USY 上的 Mn 和 Fe 金属氧化物催化剂以及单金属氧化物被制备并进行了表征。考察了催化组分之间的相互作用以及气相 NO 的引入对甲苯催化臭氧化的影响。表征结果表明，MnO、FeO 和 USY 之间存在强烈的相互作用，这增强了催化剂的氧空位和酸位含量，从而促进了活性氧物种的生成和甲苯的吸附。具有 MnO 和 FeO 双金属氧化物的 MnFeO-USY 催化剂表现出最优异的甲苯催化臭氧化性能。另一方面，反应气体混合物中存在的 NO 显著促进了甲苯的转化率和矿化率，这归因于催化剂表面上形成的硝酸盐物种，从而增加了酸位和甲苯氧化位。同时，O 和 CH 之间的反应机理被修改，其中 MnO、FeO 和 USY 之间的强相互作用基于 L-H 途径加速了反应进程。此外，表面硝酸盐物种的形成不仅促进了 L-H 途径的反应进程，而且还导致了 E-R 途径的反应发生。
