无胺体系中ZSM-5分子筛合成的研究

STUDY ON THE SYNTHESIS OF ZSM-5 ZEOLITE IN AMINE-FREE SYSTEM

以工业用水玻璃和硫酸铝为原料,采用水热法在无胺体系中合成ZSM-5分子筛,并通过XRD、N2吸附脱附等测试手段对合成样品进行了表征,考察了主要合成条件对分子筛性能的影响。研究结果表明,不同的晶化温度所需的最佳晶化时间有所不同,晶化温度高时所需的晶化时间相对较短;当pH值在9.5～10.8时,能得到性能较好的ZSM-5分子筛。研究还发现,投料硅铝比、晶种加入量、硅源温度对分子筛性能有显著的影响。

ZSM-5 zeolite was synthesized by hydrothermal crystallization method in an aminefree system to study the effect of synthesis conditions on the zeolite properties. The obtained samples were characterized by XRD and N, adsorption techniques. Results showed that the optimal crystallization time was varied with the crystallization temperature： higher crystallization temperature resulted in less crystallization time. Good quality ZSM-5 zeolite sample could be obtained with a system pH value in the range of 9.5-10.5. In addition, other factors, such as the initial system Si/Al ratio, the amount of crystal seed used and the feed temperature of silicon source also had significant influence on the quality of ZSM-5 zeolite.