高岭土微球上无胺法ZSM-5的原位合成

无胺体系中，采用水热法在焙烧高岭土微球上原位晶化合成了ZSM-5分子筛。考察了晶化温度、晶化时间、晶种加入量以及合成体系硅铝比等主要因素对分子筛合成的影响，得出了较佳的原位晶化合成条件。采用XRD、SEM、N₂吸附脱附等手段对合成样品进行了表征。结果表明：在高岭土微球上合成出了颗粒尺寸小于1 μm的小晶粒原位ZSM-5分子筛；晶化产物的比表面积、总孔容、微孔表面积和微孔孔容均明显增大，微孔分布集中于0.54 nm。

In-situ Synthesis of ZSM-5 on Kaolin Microspheres from Amine-free System

ZSM-5 zeolites were synthesized in-situ on kaolin microspheres by hydrothermal crystallization method from amine-free system. The optimal synthesis conditions were obtained. The preparation factors were investigated such as crystallization temperature, crystallization time, amount of crystal seed, silicon to aluminum ratio. The synthesized samples were characterized by X-ray diffraction, scanning electron microscopy and N₂ adsorption and desorption. The results showed that small-sized ZSM-5 crystallites, with less than 1 micron diameter were effectively formed on kaolin microspheres. The synthesized products had larger specific surface area and micropore volume. The micropore size was centered at about 0.54 nm.