通过三嵌段的共聚物做模板制备了一系列具有不同锆含量、强酸性的介孔硅材料,获得的样品通过X射线衍射分析、透射电镜分析、氮气吸附脱附、紫外可见光谱、热重分析等技术进行了表征。研究结果发现,当样品中硅和锆的物质的量比大于4时,锆物种能被完全引入到有序介孔硅结构的骨架中;然而,当样品中硅和锆的物质的量比小于4时,会出现一个由无定形硫化氧化锆组成的分离相。另外,透射电镜照片揭示了这些材料有着有序的介孔结构,氮气吸附-脱附等温线给出了属于介孔材料的IV型吸附-脱附等温线及较窄的介孔分布,异丙苯和1,3,5三异丙基苯的裂化反应出示了它们有着非常好的催化活性,尤其适合涉及大分子的催化裂化反应。
A series of mesoporous sulfated silica-zirconia materials with various Si/Zr molar ratios(2.0~5.0) have been prepared using tri-block copolymer as a template,which was characterized by X-ray diffraction,TEM,nitrogen adsorption-desorption,UV-Vis diffuse reflectance spectroscopy,infrared spectroscopy,thermal gravimetric analysis,and catalytic reactions.XRD patterns displayed that ordered mesoporous sulfated silica-zirconia materials were obtained when the molar ratio of Si/Zr was more than 4.0.When the molar ratio of Si/Zr was less than 4.0,the samples had a separated phase of amorphous sulfated zirconia.Furthermore,TEM images revealed that the mesostructure of these materials were highly ordered.N2 adsorption exhibited typical IV adsorption-desorption isotherms and uniform pore distribution.UV-Vis reflectance and IR spectra suggested that Zr atoms were incorporated into the walls of mesoporous silica.Cracking reactions of cumene and 1,3,5-triisopropylbenzene(TIPB) showed that,the ordered mesoporous sulfated silica-zirconia materials were very active in acidic catalytic reactions,especially for the cracking of large molecules.