采用不同类型的有机硅烷化SiO2作为基本合成单元,制备了具有晶内中孔的A型沸石。考察了反应碱度、Si/Al比、晶化时间等合成条件对产品的影响。结果表明,苯胺基丙基三甲氧基硅烷是合成中孔A型沸石的最佳硅烷化试剂;硅烷化试剂的应用,使中孔沸石晶化过程可以通过“键阻断原理”有效控制;沸石的中孔尺寸可以通过不同类型的有机硅烷化试剂进行调控;一定范围内,其外比表面积、中孔体积随SiO2表面硅烷化度的增加而增加。通过沸石晶化过程中的“键阻断”,可以制备具有晶内中孔的A型沸石。
Zeolite LTA with intracrystal mesopores was built using four different organic functionized SiO2 as configuration units. The effects of the synthesis conditions, including that of the alkalinity, the Si/Al molar ratio of synthesis mixture and crystallization time, on the growth process of the mesostructured zeolite crystals were investigated. Phenylaminopropyl-trimethoxysilane is the best candidate to create intracrystal mesopores in zeolite LTA crystals. The growth process of the mesostructured zeolite crystals was studied. Mesoporous size of the zeolite LTA can be modulated by selecting different kinds of organosilanes. Within a certain range, the external surface area and the mesoporous volume increase with the increasing organic function degree of the silica source. The results confirm that the synthesis method by the bond-blocking principle is an effective route to prepare zeolite LTA with tunable intracrystalline mesopores.