物理化学学报 >> 2007, Vol. 23 >> Issue (06): 905-910.doi: 10.3866/PKU.WHXB20070621

研究论文 上一篇    下一篇

烷烃在丝光沸石型分子筛中吸附和扩散行为

陈玉平; 吕玲红; 邵庆; 黄亮亮; 陆小华   

  1. 南京工业大学化学化工学院, 南京 210009

  • 收稿日期:2006-10-31 修回日期:2006-12-08 发布日期:2007-06-04
  • 通讯作者: 陆小华 E-mail:xhlu@njut.edu.cn

Adsorption and Diffusion of Alkanes in Mordenite

CHEN Yu-Ping; LU Ling-Hong; SHAO Qing; HUANG Liang-Liang; LU Xiao-Hua   

  1. College of Chemistry and Chemical Engineering, Nanjing University of Chemical Technology, Nanjing 210009, P. R. China

  • Received:2006-10-31 Revised:2006-12-08 Published:2007-06-04
  • Contact: LU Xiao-Hua E-mail:xhlu@njut.edu.cn

摘要:

采用巨正则系综蒙特卡罗(grand canonical Monte Carlo, GCMC)与分子动力学(molecular dynamics, MD)相结合的方法, 研究烷烃分子在丝光沸石(MOR)型分子筛中的吸附和扩散性质. 采用GCMC 方法研究温度为300 K、330 K时, MOR型分子筛中甲烷、乙烷、丙烷、丁烷的吸附. 研究表明, 随着压力的增加吸附量增加, 随温度的升高吸附量有所降低. 饱和吸附量从大到小依次为: 甲烷>乙烷>丙烷>丁烷. 由模拟所得到的单组分吸附等温线, 通过理想吸附溶液理论(IAST)计算二元混合物的吸附平衡相图, 模拟结果与计算结果一致. 采用分子动力学方法, 研究乙烷、丙烷在MOR分子筛上的扩散性质, 结果表明各个方向上的扩散系数不同, z方向上的扩散系数最大.

关键词: 烷烃, 分子筛, 吸附, 扩散, 分子模拟

Abstract:

Grand Canonical Monte Carlo(GCMC) and molecular dynamics (MD) techniques were employed to simulate the adsorption and diffusion properties in mordenite (MOR) zeolites. By the GCMC, the adsorption of methane, ethane, propane, and butane in MOR zeolites at 300 K、330 K was studied. The results indicated that the adsorbed amounts decreased with increasing temperature and the order of saturated adsorption amounts was methane>ethane>propane>butane. Adsorption diagrams of binary alkanes mixtures were simulated by MD and calculated by ideal adsorption solution theory (IAST). The calculated results were in agreement with the simulated results. Finally, the diffusion properties of ethane and propane in MOR zeolites were studied by molecular dynamics. The results showed that the diffusion coefficients were different in different directions and the biggest diffusion coefficients in z direction.

Key words: Alkanes, Zeolite, Adsorption, Diffusion, Molecular simulation

MSC2000: 

  • O641