Manganese oxides supported on ordered mesoporous silicas and nonordered commercial silicas were comparatively studied in terms of physical properties and catalytic behavior in the complete oxidation of propane, n-decane, toluene, and p-cymene. Manganese oxides are well-dispersed on large-pore SBA-15, KIT-6, and commercial silicas, whereas they agglomerate on small-pore HMS and MCM-41. Mn/SBA-15 contains oxide species with the best reducibility, but its two-dimensional mesopores are significantly blocked. The alkane removal efficiency depends on the amount of accessible manganese oxides; therefore, the three-dimensional Mn/KIT-6 shows better performance than the pore-blocked Mn/SBA-15. In contrast, the ignition of aromatic hydrocarbons, which needs higher temperatures than alkanes, seems more strongly dependent on the reducibility, and Mn/SBA-15 shows the lowest ignition temperatures. Despite their much smaller surface areas, nonordered commercial silicas present significant advantages in the catalytic removal of large-molecule hydrocarbons due to the favorable mass transfer in the short mesopores within their thin particles.

中文翻译：

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介孔二氧化硅负载的氧化锰，用于挥发性有机化合物的完全氧化：介观结构，氧化还原性质和烃尺寸的影响

在丙烷，正癸烷，甲苯和对甲苯的完全氧化中，从物理性质和催化性能方面比较研究了有序介孔二氧化硅和无序市售二氧化硅上负载的锰氧化物-cymene。锰氧化物很好地分散在大孔SBA-15，KIT-6和商用二氧化硅上，而它们在小孔HMS和MCM-41上聚集。Mn / SBA-15包含具有最佳还原性的氧化物，但其二维中孔被显着封闭。烷烃的去除效率取决于可及的锰氧化物的量。因此，三维Mn / KIT-6的性能优于被孔堵塞的Mn / SBA-15。相反，芳烃的点火比烷烃需要更高的温度，似乎更强烈地取决于还原性，而Mn / SBA-15的点火温度最低。尽管它们的表面积小得多，