氮气在MCM-41中毛细凝聚的模拟和理论研究

SIMULATION AND THEORETICAL STUDY OF CAPILLARY CONDENSATION OF NITROGEN IN MCM-41

采用巨正则系综Monte Carlo方法(GCMC)以及基于扩展基本度量理论和MBWR状态方程的密度泛函理论,研究了77.4 K时氮气在不同孔径的MCM-41分子筛中吸附的密度分布和吸附等温线。提出的平均场权重密度泛函理论,克服了平均场近似预测主体相热力学性质时的偏差,获得的密度分布和吸附等温线与GCMC分子模拟结果有着很好的一致性。

Grand ensemble Monte Carlo simulations and a density functional theory（DFT） based on the modified fundamental-measure theory and the modified Benedict-Webb-Rubin equation of state are used to investigate a density profile and adsorption isotherm of nitrogen in MCM-41 materials. Compared to the mean-field theory,the proposed DFT is able to reproduce the bulk properties of nitrogen.The density profiles from the DFT agree well with those from the GCMC simulations.