动态水热晶化法合成纳米NaY型分子筛

Synthesis of Nanosized NaY Molecular Sieve under Dynamic Hydrothermal Crystallization

以工业级水玻璃为原料在无添加剂条件下,采用动态水热晶化法制备了纳米NaY型分子筛。利用XRD、SEM和TEM分析,研究了晶种胶陈化时间、成胶温度和方式及碱度对NaY分子筛粒径大小及结构组成的影响。结果表明,采用晶种胶陈化时间为4 d,20℃条件下,采用合适的成胶方式可以降低产品的晶粒尺寸;增大反应体系的碱度可降低NaY分子筛的粒径和骨架硅铝比。通过优化合成条件,制备出平均粒径为82~105 nm,且粒度分布较窄的纳米NaY型分子筛。

Nanosized NaY molecular sieves with high crystallinity were synthesized using commercial raw materials without the presence of additive via dynamic hydrothermal crystallization.The influences of aging period of the seed-gel,the temperature and route of gelation,and the alkalinity of the initial gel on the grain size,relative crystallinity and farmework SiO2/Al2O3 of NaY nanoparticles were investigated by XRD,SEM and TEM.The results show that the grain size was effectively controlled by adding seed-gel of aging 4 d and suitable gelation temperature and route.The grain size and framework SiO2/Al2O3 ratio decreased when reducing the alkalinity of synthetic system.The nano-NaY products with the average grain size at a range of 82-105 nm can be synthesized by the optimized synthesis conditions.