Abstract:

The adsorption behavior of water on ZSM-5 was simulated by using the grand canonical ensemble Monte Carlo (GCEMC) method.The geometric structure and properties of ZSM-5 were first analysed by the Connolly surface methods and Solvent surface methods.Simulation results showed that Connolly free volume and the volume of water molecular inaccessible in zeolite gradually decreased with decreasing zeolite ratio n_Si/n_Al.ZSM-5 zeolite was strongly hydrophobic under low pressure conditions, and its adsorption capacity would increase with increasing pressure.Desorption curves had a certain lag, and this proved the existence of capillary rally phenomenon.The adsorption capacity of ZSM-5 zeolite exchanged by K⁺, Na⁺, Ca²⁺ had a significant change, and increased with increasing aperture size.The adsorption capacity of zeolite increased with Si atoms replaced by Ti atoms in zeolite matrix, while it would decrease with increasing number of Al atoms replaced by Ti atoms.At the same adsorption capacity, the absorption heat reduced with increasing n_Si/n_Al ratio or aperture size.

Key words:

水, ZSM-5型分子筛, 吸附, 分子模拟

摘要： 构建了ZSM-5型分子筛物理模型，采用Connoly表面方法和Solvent表面方法对ZSM-5型分子筛的几何结构和性质进行了模拟分析。通过巨正则系综蒙特卡罗方法(GCMC)模拟研究了水蒸气在ZSM-5型分子筛上的吸附特性。通过模拟方法看到了实验难以表征的水蒸气在分子筛中具体吸附位，研究了压力、温度和硅铝比对ZSM-5型分子筛吸附性能的影响及其吸附热的变化规律。

关键词:

水, ZSM-5型分子筛, 吸附, 分子模拟