【摘要】 制备纯硅的介孔分子筛MCM-41,具有不同Si/Al的Al-MCM-41,以及含有B原子和Ti原子的B-Al-MCM-41和Ti-MCM-41的试样。小角X射线粉末衍射(XRD)分析表明,样品均具有MCM-41的结构特征,N2吸脱附研究表明,样品呈现Ⅳ型吸附等温线,具有孔径分布均一的中孔结构。利用27AlMASNMR研究了试样中Al的化学环境。结果表明,随铝含量的增加,四配位骨架铝和六配位骨架外铝同时增多,并且由非骨架四配位铝或骨架扭曲四配位铝所产生的“不可观察铝”也增多。更多还原

【Abstract】 Mesoporous molecular sieves MCM-41 with incorporated structural hybrid atoms (Al, B, and Ti)are prepared using hydrothermal synthesis technology. Low angle XRD and nitrogen adsorption measurement indicate that all samples have typical hexagonal phase structure and uniform pore size distribution except Ti-MCM-41.Solid state ~27Al MAS NMR spectra shows that tetrahedral Al (framework) and octahedral Al (extra-framework) increase with the decrease of Si/Al,and tetrahedral extra-framework Al and/or distorted tetrahedral framework Al increase simultaneously.更多还原