高纯度中孔分子筛MCM-41的合成与表征  

Synthesis and Characterization of High quality Mesoporous Molecular Sieve MCM 41s

作　　者：许宜铭[1] 

机构地区：[1]浙江大学化学系

出　　处：《高等学校化学学报》1999年第5期670-674,共5页Chemical Journal of Chinese Universities

摘　　要：用不同ｐＨ值的混合物制备了不同孔径的全硅ＭＣＭ－４１和不同金属离子取代的Ｍ－ＭＣＭ－４１（Ｍ＝Ａｌ，Ｍｎ，Ｆｅ和Ｖ）分子筛．这些试样均呈现ＭＣＭ－４１的Ｘ射线粉末衍射特征峰和Ⅳ型氮气吸附等温线，但混有不同含量的无定形氧化硅．样品中ＭＣＭ－４１晶体的含量与溶胶的ｐＨ值和所用表面活性剂的碳链链长有关．骨架硅的金属离子取代降低了ＭＣＭ－４１的有序度。Siliceous MCM 41 samples with two different pore size and metal substituted MCM 41 samples with different metals have been synthesized at different pH of the mixture, and characterized by X ray powder diffraction and nitrogen adsorption analysis. The results show that all the samples exhibit a typical XRD diffraction of MCM 41 and an adsorption isotherm of type Ⅳ, but there exists a considerable amount of amorphous silica in the samples. The sample prepared at pH=11(MCM 3) shows the best in quality among the others, and has less content of amorphous silica phase. When the MCM 3 is regarded as a standard, the sample prepared without pH adjustment contains only 36% of pure MCM 41 crystallites, while the sample prepared at pH=10.5 has 84% of pure MCM 41 phase. It has also been observed that the quality of the resulted samples is decreased when a shorter chain surfactant is used. When the metal substituted M MCM 41 (M=Al, Mn, Fe, V) is prepared at pH=11, their quality can be improved. However, the diffraction intensity of d 100 phase is still lower than that of the corresponding siliceous MCM 41, and decreases accordingly from Al to V.

关 键 词：全硅 MCM-41 金属聚代 中孔分子筛 分子筛 

分 类 号：TQ426.65[化学工程] TQ424.25