具有高比表面积和微孔-介孔分子筛的合成

Synthesis of Mesoporous Materials With Large Surface Area and Micropore Duct

采用纳米组装法合成介孔分子筛材料,用XRD,BET,SEM,TEM,IR对其进行表征。XRD测试显示此种分子筛属于六方晶相,并且只存在此单一晶相;N2吸附-脱附测试显示,此种分子筛具有微孔和中孔结构,比表面积高达1 135 m2/g;SEM照片显示分子筛晶体呈团聚状地生长在一起,晶界不再明显;TEM照片显示分子筛表面分布着较密集的孔道,而且孔道尺寸不均一;吡啶红外吸附光谱显示,此种分子筛与HMCM-41分子筛相比,具有更多的B酸和L酸中心。对于大分子烃1,3,5-三异丙基苯的催化裂化反应,与HMCM-41分子筛相比,此种分子筛的活性远大于HMCM-41分子筛。

The mesoporous materials were synthesized by an nanometer assembly crystallization process and characterized by XRD,BET,SEM,TEM and NH3--TPD. The results of XRD show that the zeolite belongs to hexagonal symmetry, and it is a pure phase. The result of N2 adsorption--desorption isotherm shows that the zeolite has both micropore and mesopore structure and Langmuir surface area is 1 135 m^2/g. The SEM photos show that crystalloid of the zeolite grows all round, and the aggregation of some grain makes the circumscription blurry. The TEM photos show that the zeolite has dense aperture and inhomogeneous dimension. IR shows that the zeolite presents much more Bronsted and Lewis acidic sites than HMCM--41. The catalytic cracking activity of 1,3,5--triisopropylbenzene over the zeolite is much higher than that over HMCM--41 due to its structure and more acid amount.