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以钨酸钠和正硅酸乙酯为前驱体直接合成高含量WO3掺杂介孔氧化硅泡沫(MCF)催化剂.在773K焙烧后显示出更高的热稳定性.小角X射线散射,N2-物理吸附和透射电子显微镜结果表明钨物种嵌入后,材料仍保持MCF特征的三维织构介孔特征.紫外拉曼和紫外可见漫反射光谱结果表明钨物种主要以孤立的或者低聚态的氧化钨形式存在,所以在氧化钨质量分数(w)低于20%时氧化钨物种能够高度分散在载体上.在环戊烯选择氧化制戊二醛反应中,反应16h后环戊烯的转化率达到100%,戊二醛的产率达到83.5%.催化剂重复利用实验表明催化剂的稳定性较好,没有钨物种的脱落.这种优异的催化性能归结于合适的氧化钨含量和高分散的钨物种.
Direct synthesis of WO3-doped mesoporous silica foam (MCF) catalysts using sodium tungstate and tetraethyl orthosilicate as precursors showed higher thermal stability after calcination at 773 K. Small angle X-ray scattering, N2-physical The results of adsorption and transmission electron microscopy showed that the three-dimensional textured mesoporous MCFs remained after the tungsten species were embedded.The results of UV-Raman and UV-Vis diffuse reflectance spectroscopy showed that the tungsten species mainly existed in the form of isolated or oligomeric tungsten oxide , The tungsten oxide species can be highly dispersed on the support when the mass fraction of tungsten oxide (w) is less than 20% .In the selective oxidation of cyclopentene to glutaraldehyde, the conversion of cyclopentene reaches 100 %, The yield of glutaraldehyde reached 83.5% .The experiments of catalyst re-utilization showed that the stability of the catalyst was better and no tungsten species were shed.The excellent catalytic performance was attributed to the suitable tungsten oxide content and highly dispersed tungsten species.