Methanol diffusion in H-ZSM-5 catalysts as a function of loading and Si/Al ratio: A classical molecular dynamics study
Methanol diffusion in H-ZSM-5 catalysts as a function of loading and Si/Al ratio: A classical molecular dynamics study
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DOI：
10.1016/j.catcom.2022.106415
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发表时间：
2022-01
影响因子：
3.7
通讯作者：
Claire-Louise M. Woodward;A. J. Porter;K. S. Morton;A. O’Malley
中科院分区：
文献类型：
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作者：
Claire-Louise M. Woodward;A. J. Porter;K. S. Morton;A. O’Malley
在 Si/Al = 15, 47, 95 191 的框架和全硅质系统中，使用经典分子动力学在 373 –423 K 下研究 H-ZSM-5 中的甲醇扩散，每个晶胞加载 3 和 5 个分子。虽然较低的负载量表现出较高的扩散率，但在 Si/Al = 15 和 95 之间的负载量下，自扩散率都会增加，之后它们与成分无关。扩散率随 Si/Al 比的变化趋势可以用甲醇-酸位点相互作用来解释，而负载量的趋势可以用甲醇-甲醇相互作用和催化剂孔中产生的甲醇结构来解释。
Methanol diffusion in H-ZSM-5 was studied using classical molecular dynamics at 373 –423 K, using loadings of 3 and 5 molecules per unit cell, in frameworks with Si/Al = 15, 47, 95 191 and a fully siliceous system. While the lower loading exhibits higher diffusivity, self-diffusivities increase at both loadings between Si/Al = 15 and 95, after which they are independent of composition. The trend in diffusivity with Si/Al ratio is explained in terms of methanol-acid site interactions, while the trend with loading is explained in terms of methanol-methanol interactions and the resulting methanol structure in the catalyst pores.