小晶粒NaY分子筛的快速合成及表征

CHARACTERIZATION AND RAPID SYNTHESIS OF LITTLE SIZE NaY ZEOLITE

以硅酸钠和硅溶胶分别作为导向剂和母液的硅源，通过控制导向剂和反应体系的碱度对小晶粒NaY分子筛的水热合成进行了研究，并借助XRD、XRF、SEM、激光粒度分布仪（DLS）等分析手段对产物进行了表征。结果表明，n（Na2O2）/n（Al2O3）高的导向剂对快速合成NaY分子筛有利，随着合成体系n（Na2O2）/n（Al2O3）的升高，晶化速率明显加快，产物初级颗粒的粒径有所减小，但团聚现象有所加剧。采用n（Na2O2）/n（Al2O3）为22的导向剂，体系n（Na2O2）/n（Al2O3）控制为5．19，在100℃下晶化3．0h，可快速合成出粒径在0．5μm左右的NaY分子筛。

A series of hydrothermal synthesis were carried out in order to obtain little size NaY zeolite via adjusting the molar ratios of NazO to Al2O3 in seed gel and feed stock gel, where the sodium silicate and silica sol were chosen as silica source for the seed gel and the feed stock gel, respectively. The products were characterized by XRD, XRF, SEM and DLS techniques. The results showed that the seed gel with high molar ratio of NazO to Al2O3 was beneficial to the synthesis process. With increasing the molar ratio of Na2O to Al203, the crystallization duration was reduced obviously and the primary particle size of the product decreased notably, while the secondary particle size grew up gradually. When the molar ratios of Na2O to Al2O3 in the seed gel and overall gel for the synthesis were 22 and 5.19, respectively, NaY zeolite with particle size of around 0.5 μm could be quickly synthesized after 3.0 h of crystallization at 100℃.