三元孔道结构纳米ZSM-5分子筛团聚体的合成

Synthesis of aggregated nano-sized ZSM-5 zeolite with ternary pore structure

采用正丁胺和ZSM-5晶种双模板体系水热合成了一系列ZSM-5分子筛,考察了晶种、正丁胺添加量和晶化条件对分子筛物理化学性能、孔道结构和形貌的影响。对所得分子筛分别进行X射线衍射(XRD)、氮气吸-脱附、扫描电子显微镜(SEM)表征分析。结果表明:分子筛为三元孔道结构的纳米ZSM-5分子筛团聚体,正丁胺和晶种在合成过程中具有协同作用。在正丁胺与二氧化硅物质的量比为0.26、晶种添加量为3%(质量分数)、在120℃晶化24 h后再在170℃晶化48 h条件下合成的分子筛总比表面积和外比表面积分别为364 m^2/g和59 m^2/g。

A series of ZSM-5 zeolite were hydrothermally synthesized by using the double template system of n-butylamine and ZSM-5 crystal seed.The influence of content of seed and n-butylamine,and crystallication process on the physicochemical properties,pore structure and morphology of obtained zeolites were investigated.The obtained zeolites were subjected to X-ray diffraction(XRD),N2 adsorption-desorption and scanning electron microscopy(SEM)characterization analysis.The analysis results showed that the obtained material was aggregated nano-sized ZSM-5 zeolite with ternary pore structure,and n-butylamine and seed crystals had a synergistic effect in the synthesis process.Under the synthesis conditions of n(n-butylamine)/n(SiO2)=0.26,seed addition amount of 3%(mass fraction)and crystallization at 120℃for 24 h and then at 170℃for 48 h,the specific surface area and external surface area were 364 m^2/g and 59 m^2/g,respectively.