物理化学学报Issue(6)：1025-1034,10.DOI:10.3866/PKU.WHXB201504141
反渗透过程中双壁碳纳米管通水阻盐性能的分子动力学模拟
Molecular Dynamics Simulation of Reverse-Osmotic Salt Rejection and Water Transport through Double-Walled Carbon Nanotube
摘要
Abstract
Molecular dynamics simulation was used to study the effect of the outer-wal on water flux in the inner channel by varying the inter-layer spacing of unconventional double-wal ed carbon nanotube (DWCNT) under reverse-osmosis conditions. Salt rejection and the water transport behavior inside the DWCNT were also examined. In the simulation, 0.5 mol∙L-1 NaCl aqueous solution was used to mimic seawater, and the chiral index of the inner-wal was fixed at (8, 8). A constant force on the salt solution produced pressure. Calculation of the number density profile of ions along the DWCNT axis showed that the water could be separated completely from the NaCl aqueous solution in some types of DWCNTs studied. Analyses of the hydrogen-bond lifetime, potential of mean force, and dipole moment distribution of the water molecules inside the DWCNT showed different permeabilities by water molecules and ions. An increase in the inter-layer spacing improved water flow in the DWCNT, which decreased the salt rejection performance. Final y, it was found that DWCNT with an inter-layer spacing of 0.815 nm gave the optimum balance between water flux and salt rejection. This study provides a molecular insight into the use of DWCNT in desalination, and wil enable the design of improved reverse-osmosis membranes with high performance in terms of salt rejection and water permeability.关键词
双壁碳纳米管/分子动力学模拟/管间距/反渗透/海水淡化Key words
Double-wal ed carbon nanotube/Molecular dynamics simulation/Inter-layer spacing分类
化学化工引用本文复制引用
谌庄琳,贺高红,张宁,郝策..反渗透过程中双壁碳纳米管通水阻盐性能的分子动力学模拟[J].物理化学学报,2015,(6):1025-1034,10.基金项目
The project was supported by the National Natural Science Foundation for Distinguished Young Scholars of China (21125628), Fundamental Research Funds for the Central Universities, China (DUT14RC(3)077) and State Key Laboratory of Fine Chemicals (Panjin) Project, China (JH2014009).国家杰出青年科学基金项目(21125628),中央高校基本科研业务费专项资金(DUT14RC(3)077)和盘锦市精细化工国家重点实验室建设经费(JH2014009)资助 （21125628）
