物理化学学报 >> 2012, Vol. 28 >> Issue (03): 573-577.doi: 10.3866/PKU.WHXB201112191

理论与计算化学 上一篇    下一篇

以荷电化碳纳米管构筑正渗透膜用于海水淡化的分子动力学模拟

李海兰, 贾玉香, 胡仰栋   

  1. 中国海洋大学化学化工学院, 山东青岛 266100
  • 收稿日期:2011-08-31 修回日期:2011-12-09 发布日期:2012-02-23
  • 通讯作者: 贾玉香 E-mail:jiayx76@yahoo.com.cn
  • 基金资助:

    国家自然科学基金(20806076)和山东省自然科学基金(ZR2011EMQ004)资助项目

Molecular Dynamics Simulation of the Desalination of Sea Water by a Forward Osmosis Membrane Containing Charged Carbon Nanotubes

LI Hai-Lan, JIA Yu-Xiang, HU Yang-Dong   

  1. College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, Shandong Province, P. R. China
  • Received:2011-08-31 Revised:2011-12-09 Published:2012-02-23
  • Contact: JIA Yu-Xiang E-mail:jiayx76@yahoo.com.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20806076) and Natural Science Foundation of Shandong Province, China (ZR2011EMQ004).

摘要: 受传统膜科学中分离膜的荷电化可提升膜盐水分离效能的启发, 在前期工作基础上尝试以荷电化碳纳米管CNT(8, 8)为水通道仿生构筑正渗透膜, 利用分子动力学模拟的方法研究水分子在膜中的传递行为. 模拟中, 以0.5 mol·L-1氯化钠溶液模拟海水, 1 mol·L-1的氯化镁溶液为汲取液, 考察不同电量电荷修饰对碳纳米管正渗透膜中水分子密度分布、扩散系数以及水通量的影响. 结果显示, 电荷修饰对碳纳米管中水分子的密度分布和扩散速率以及水通量影响较显著, 当碳纳米管管口荷电量为-0.3e时, 碳纳米管膜可获得最大水通量.

关键词: 正渗透, 碳纳米管, 荷电膜, 分子动力学模拟, 海水淡化

Abstract: Spurred by traditional membrane science in which a charged membrane can improve separation efficiency, a forward osmosis membrane containing charged“armchair-type”(8, 8) carbon nanotubes (CNTs) was developed and the transport phenomena of water molecules in this membrane were investigated. In the simulation, 0.5 mol·L-1 NaCl was chosen to mimic seawater, and 1 mol·L-1 MgCl2 was chosen as the draw solution. The effects of electric charge on the density distribution, diffusion of water molecules, and the water flux of the membrane were investigated in detail. Modifying the CNT membrane by charge significantly changes the density distribution, diffusion, and flux of water molecules. The membrane containing CNTs modified by -0.3e can achieve the highest water flux of those developed.

Key words: Forward osmosis, Carbon nanotube, Charged membrane, Molecular dynamics simulation, Desalination of sea water