高岭土/尿素插层复合材料合成ZSM-5分子筛及表征

研究了直接插层法制备高岭土/尿素插层复合材料和以该材料采用原位技术合成含ZSM-5分子筛的催化复合材料。重点研究了插层率、脱嵌速率、插层复合材料加入量对合成分子筛复合材料的影响。采用粉末X射线衍射法（XRD），红外光谱（FT-IR），热重-差热（TG-DTA），N2 静态吸附法和电子扫描电镜（SEM）对样品进行表征。结果表明，在合成体系中加入高岭土/尿素插层复合物合成出的ZSM-5分子筛物相单一。随着插层复合物的插层率增加，ZSM-5分子筛的结晶度先增加随后降低。当插层率为62%时，ZSM-5分子筛的结晶度较低。当22%插层率的插层复合物的加入量为3%时，ZSM-5分子筛的结晶度达到65%。与不添加插层复合物合成的产物相比，ZSM-5分子筛的结晶度提高了54.8%。合成的ZSM-5分子筛复合材料具有较好的热稳定性和多级孔道结构，其粒径约为2.5μm，BET比表面积为236m2/g，孔径为10.6nm。

Synthesis and Characterization of ZSM-5 Molecular Sieve Made from Kaolin/Urea Intercalation Composite

In this paper, the kaolin/urea intercalation composites prepared by direct intercalation method and the catalysis composites containing ZSM-5 molecular sieve synthesized based on the kaolin/urea intercalation composites by an in-situ crystallization technique were investigated. The effects of the intercalation ratios and de-intercalation rate and the amounts of added kaolin/urea intercalation composite on the synthesis of the catalysis composites containing the ZSM-5 molecular sieve were studied. The samples were characterized by X-ray diffraction, FT-IR, TG-DTA, N2 adsorption-desorption, and SEM, respectively. The results showed that the structure of the samples prepared by kaolin/urea intercalation composite was pure ZSM-5 molecular sieve. The crystallinity of ZSM-5 molecular sieve increased at first and then decreased with the increase of intercalation ratio of kaolin/urea intercalation composite. When the intercalation ratio was 62%, the crystallinity of ZSM-5 molecular sieve was lower. When the amount of added kaolin/urea intercalation composite with an intercalation ratio of 22% was 3%, the crystallinity of ZSM-5 zeolite was improved to reach 65%. Compared to the crystallization product formed without adding kaolin/urea intercalation composite, the crystallinity of ZSM-5 molecular sieve has increased by 54.8%. The catalytic composites containing ZSM-5 molecular sieve had better thermal stability with a wide pore structure, featuring a particle diameter of about 2.5 μm, a BET specific surface area of 236 m2/g, and a pore size of 10.6 nm.