有机蒸气/氮气混合物透过炭膜的非平衡分子动力学模拟  

Molecular Dynamics Simulation of Organic Vapor Permeation through Carbon Membranes

作　　者：钟璟[1] 邵伟[1] 夏庆[1] 宋晓丽[1] 陈燕[1] 

机构地区：[1]江苏工业学院化学工程系,江苏常州213164

出　　处：《天然气化工—C1化学与化工》2008年第2期24-28,32,共6页Natural Gas Chemical Industry

基　　金：国家自然科学基金(20406007);2006年江苏省精细石油化工重点实验室基金资助项目

摘　　要：基于考虑渗透过程中外加力场影响的非平衡分子动力学方法,建立了计算有机蒸气/氮气混合物透过多孔C膜的渗透系数和分离因子的方案;并对甲烷/氮气(CH4/N2)和丙酮/氮气(CH3COCH3/N2)两种混合物透过炭膜的渗透过程进行计算。主要讨论了计算模型的建立和计算方法的选择。计算出的渗透系数和分离因子与文献中的计算结果或实验结果具有可比性,CH4/N2混合物透过0.75nm炭膜的分离机理为偏离Knudsen扩散、伴有表面扩散产生,分离因子为1.836;丙酮/N2混合物透过4.42nm炭膜的分离机理为毛细管冷凝,分离因子为44.46。炭膜可有效地用于回收丙酮。A scheme that could be used to compute the permeability and separation factor of organic vapor/nitrogen mixture permeation through porous carbon membranes was proposed, which based on non-equilibrium molecular dynamics method and considered the effect of extra force field. The permeation process of methane/nitrogen and acetone/nitrogen mixtures through carbon membranes were simulated by this scheme, and the permeability and separation factor computed in this work consisted with the computational or experimental results in the references. The construction of computational model and integration method were mainly discussed. The results showed that the separation mechanism of methane/nitrogen mixture permeation through 0.75nm carbon membrane was departure Knudsen diffusion accompanied by surface diffusion, and the separation factor of this system is 1.836. The separation mechanism of acetone/nitrogen mixture permeation through 4.42nm carbon membrane was capillary condensation, and the separation factor is 44.46. Carbon membranes can be effectively used for the recovery of acetone.

关 键 词：炭膜 有机蒸气 分子动力学 分离因子 渗透系数 丙酮 

分 类 号：O604[理学—化学] TQ028.8[化学工程]