不同晶化条件对 ZSM-34分子筛性质的影响

摘要

以氯化胆碱为模板剂，采用模板剂法单段晶化、模板剂法两段晶化及晶种辅助的两段晶化法水热合成了不同晶粒尺寸的 ZSM-34分子筛。应用 X 射线衍射（XRD）、扫描电子显微镜（SEM）、低温 N2吸附-脱附、氨气程序升温吸附-脱附（NH3-TPD）、核磁共振（NMR）等手段对合成样品进行表征。结果表明：两段晶化法能够将晶化时间从96 h 缩短至72 h，加入晶种后晶化时间降至24 h；低温有利于 ZSM-34分子筛的均匀成核；结合晶化曲线分析发现晶种辅助的两段晶化法有利于快速合成性质稳定的 ZSM-34分子筛。%ZSM-34 with different sizes was synthesized successfully employing choline chloride as a template under crystallization conditions of single-stage,two-stage,two-stage with the help of seed, respectively. The products were characterized by X-ray diffraction,scanning electron microscopy,N2 adsorption∕desorption,NH3-temperature programmed desorption and NMR techniques. The results show that two-stage crystallization has advantages in shorter crystallization time from 96 h to 72 h, while the two-stage crystallization with the help of seed appears much more outstanding,the crystalliza-tion process is finished after only 24 h. The crystallization curve analysis indicates that two-stage crys-tallization with the help of seed is helpful to rapidly synthesize ZSM-34 with stable properties.