氟离子体系中制备MCM－48介孔分子筛

Preparation of MCM-48 Mesoporous Molecular Sieves in the F-solution

利用溶胶-凝胶水热法，以阳离子表面活性剂十六烷基三甲基溴化铵（CTAB）为模板，正硅酸乙酯（TEOS）为硅源，在不同n（F）／n（Si02）（摩尔比为0～0．2）下合成了MCM-48介孔分子筛。通过粉末X射线衍射（XRD），N2吸附-脱附、扫描电镜（SEM）对合成样品进行表征。结果表明：反应物中加入F，有利于制备出有序性好、骨架聚合度高、热稳定性和水热稳定性好的MCM-48介孔分子筛材料。由XRD谱图发现：n（F）／n（SiO2）在0．0～0．1时均能生成MCM-48，且随着n（F）／n（SiO。）比率的增大所得样品的结晶度增强，有序度增加；当n（F）／n（SiO2）增大到0．2时，样品的结晶度减弱，有序度降低。

Using cetyltrimethylammonium bromide（CTAB） as template, tetraethylorthosilicate （TEOS） as silica source, MCM-48 molecular sieves were synthesized by sol-gel hydrothermal method at different F/SiO2 ratios（molar ratio： 0.05, 0. 1）. The samples were characterized by powder X-ray diffraction （XRD）, N2 sorption and scanning electron microscopy （SEM） measurements. The results showed that introduction of fluoride could synthesize ordered, higher thermal and hydro-thermal stability MCM-48 mesoporous molecular sieves. Moreover, with increasing of F/SiO2 molar ratio, stability of MCM-48 samples was improved.