Synthesis and molecular dynamic simulation of high uniformity and crystallinity ZSM-5

doi:10.3969/j.issn.0438-1157.2013.04.051

Abstract

Abstract: Molecular dynamic simulations were conducted to study the crystallization process of ZSM-5 zeolite from engineering perspective.The influence of temperature on radial distributions of oxygen of water were calculated, and the results indicated that the formation process of ZSM-5 zeolite might be divided into two stages, precursor formation and nucleation stage at a low temperature and crystal growth stage at a higher temperature.At a higher temperature, homogenous nucleation was suppressed, therefore, the best nucleation temperature was found at around 350 K.ZSM-5 zeolite was synthesized by using two-step procedure in accordance to the simulation results.High uniformity and high crystallinity could be obtained, which verified the simulation results.Interaction energy between template molecule and ZSM-5 zeolite at different temperatures was also calculated by using molecular dynamics.The results showed that when temperature was above 350 K, template molecules would form stronger tie with zeolite surface with increasing temperature, which might lead to intensified crystal growth and surface nucleation.SEM images of surface morphology of ZSM-5 synthesized at different temperatures confirmed this finding.

Key words: ZSM-5, molecular dynamics, radial distribution function, zeolite growth mechanism

关键词: ZSM-5, 分子动力学, 径向分布函数, 分子筛生长机理

CLC Number:

TQ012

CUI Xianxian, GUAN Hui, HUANG Min. Synthesis and molecular dynamic simulation of high uniformity and crystallinity ZSM-5[J]. CIESC Journal, 2013, 64(4): 1493-1498.

崔贤羡, 管卉, 黄民. 高结晶度ZSM-5分子筛合成及分子动力学模拟[J]. 化工学报, 2013, 64(4): 1493-1498.

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