A型分子筛生长的理论模型

The crystal growth model of zeolite A

以XRD、TEM、电子衍射对A型分子筛水热晶化过程中晶体生长作了实时观察 ,分析了晶体生长过程中晶体的聚集行为与演化特征 ,提出了A型分子筛生长的叠合生长模型 ,认为 ,水热体系经过一个晶化诱导阶段后 ,大量的纳米晶形成 ,纳米晶作为生长基元 ,相互迅速聚集直接叠合演化为微米多晶体 ,叠合过程不同于邻位面生长所描述的生长基元一个个按次序嵌入晶面 。

The morphological evolution of zeolite A in hydrothermal system was studied via XRD, TEM, electron diffraction. It was found that a phenomenon of aggregation of nano crystals of zeolite A existed in the crystallization process, and microcrystals were derived from nano crystal aggregating directly. The splicing growth model of zeolite A was presented, which was described as that, an induction period existed at beginning of crystallization, after that, a lot of nanocrystals initiated immediately, the nanocrystals aggregated and spliced with each other as slices to form a larger crystal.