镁碱沸石结晶度及晶体形貌的影响因素

Influence Factors on the Crystallinity and Morphology of Ferrierite

以硅溶胶为硅源,偏铝酸钠为铝源,乙二胺为模板剂制备镁碱沸石。考察了晶化温度、晶化时间、碱度、陈化时间和晶种加入量对镁碱沸石结晶度和晶体形貌的影响。用X射线衍射仪(XRD)、扫描电子显微镜(SEM)等对所合成的样品进行了表征。结果表明:在碱度为0.12~0.15、晶化温度为160℃、晶化时间为60 h的条件下能够合成出晶化良好的样品;随着晶化温度的升高样品结晶度先升高后降低,其晶体尺寸逐渐增加;随着晶化时间的延长样品的结晶度和晶体尺寸先增加后趋于稳定;适当温度的陈化可以减小晶体尺寸,而添加晶种则可以显著改变晶体的形貌和尺寸。

Ferrierite zeolite was synthesized by hydrothermal method using silica sol,sodium aluminate and ethylenedianmine as silicon source, aluminum source and organic template separately. The influence of synthsis factors such as crystallization time, crystallization temperature, alkalinity, ageing and the amount of seed on the crystallinity and crystal morphology were investigated. The samples were characterized by XRD and SEM. The result indicates that the pure ferrierite zeolite could be synthesized with a suitable alkalinity （0. 12-0. 15） , crystallization temperature （ 160 Tl ） and crystallization time （60 h ） . The higher the crystallization temperature, the bigger the crystal size was, but the crystallinity went up at first and then downd as the crystallization temperature increased. The crystallinity and crystal size increased initially as the crystallization time extended and stabilized afterwards. A suitable ageing temperature and time could reduce the crytal size, while the adding seed could change the morphology and size significantly.