1. 西安交通大学陕西省能源化工过程强化重点实验室,西安,710049
2. 西安交通大学化学工程与技术学院,西安,710049
网络首发:2019-02-10,
纸质出版:2019
移动端阅览
纪松灿 1, 钱晓炜 1, 曾飞祥 1, 等. 利用分子动力学模拟水和盐在磺化聚苯乙烯-乙烯/丁烯-苯乙烯膜内的扩散行为[J]. 西安交通大学学报, 2019,53(2):170-178.
Water and Salt Diffusion Behavior of Sulfonated Poly (Styrene-Ethylene/Butylene-Styrene)Block Copolymer Membrane with Molecular Dynamic Simulation[J]. 2019, 53(2): 170-178.
纪松灿 1, 钱晓炜 1, 曾飞祥 1, 等. 利用分子动力学模拟水和盐在磺化聚苯乙烯-乙烯/丁烯-苯乙烯膜内的扩散行为[J]. 西安交通大学学报, 2019,53(2):170-178. DOI: 10.7652/xjtuxb201902023.
Water and Salt Diffusion Behavior of Sulfonated Poly (Styrene-Ethylene/Butylene-Styrene)Block Copolymer Membrane with Molecular Dynamic Simulation[J]. 2019, 53(2): 170-178. DOI: 10.7652/xjtuxb201902023.
为了深入探究磺化聚苯乙烯-乙烯/丁烯-苯乙烯(S-SEBS)膜脱盐机理
采用分子动力学(MD)模拟研究了S-SEBS膜的微观结构及水和盐在膜内的扩散行为
对比不同盐浓度条件下水分子和盐离子在膜内的扩散系数。研究结果发现
水分子和盐离子在膜内有特定的位置分布和不同的扩散性能。水分子在膜内亲水区聚集成团簇
当膜内含水率较高时
水分子在膜内易形成连续的纳米传递通道; Na
+
由于强静电吸引作用与磺酸根之间的距离较近
Cl
-
则由于静电排斥作用远离磺酸根。H
2
O、Cl
-
和Na
+
的扩散系数均随着料液浓度的增加而减小
并在同一体系下按H
2
O、Cl
-
和Na
+
顺序由大到小排列
这与水和盐的尺寸、电荷效应及膜的微观结构有关。盐离子在聚合物膜内以水合离子的形式存在
减小了自身在膜内的有效自由体积
增大了传质阻力
从而增大了S-SEBS膜对水分子和盐离子的扩散选择性
这对获得高盐截留率有至关重要的作用。
To deeply reveal the mass transfer mechanism of water and salt in S-SEBS membrane for pervaporation(PV)desalination
a molecular dynamic simulation is conducted to research the micro-structure of S-SEBS membrane and the diffusion behaviors of water and salt ions in the membrane. The results show that water molecules and salt ions are endowed with specific distribution and different diffusion properties in the membrane
and water molecules aggregate into clusters in the hydrophilic region of the membrane. When the water content gets higher
water molecul
es easily serve as continuous nano-channels in the membrane. Na
+
is close to sulfonic acid groups due to the strong electrostatic attraction while Cl
-
is far away from sulfonic acid groups due to the electrostatic repulsion. The diffusion coefficients of H
2
O
Cl
-
and Na
+
decrease with the increasing salt concentration in an order from large to small in the same system
which is related to the size of water molecule and salt ions
charge effect and the micro-structure of the membrane. The hydration form of ions in the polymer membrane reduces the effective free volume and increases the mass transfer resistance
which enlarges the diffusion selectivity of S-SEBS membrane for water molecules and salt ions and thus contributes to the high salt rejection of the membrane in PV process.
WANG Q, LI N, BOLTO B, et al. Desalination by pervaporation: a review [J]. Desalination, 2016, 387: 46-60.
ELMA M, YACOU C, WANG D K, et al. Microporous silica based membranes for desalination [J]. Water, 2012, 4(3): 629-649.
SEMENOVA S I, OHYA H, SOONTARAPA K. Hydrophilic membranes for pervaporation: an analytical review [J]. Desalination, 1997, 110(3): 251-286.
PARK H B, FREEMAN B D, ZHANG Z B, et al. Highly chlorine-tolerant polymers for desalination [J]. Angewandte Chemie International Edition, 2008, 47(32): 6019-6024.
HOU H, VONA M L D, KNAUTH P. Building bridges: crosslinking of sulfonated aromatic polymers: a review [J]. Journal of Membrane Science, 2012, 423/424(51): 113-127.
WEISS R A, SEN A, WILLIS C L, et al. Block copolymer ionomers: 1 Synthesis and physical properties of sulphonated poly(styrene-ethylene/butylene-styrene)[J]. Polymer, 1991, 32(10): 1867-1874.
YANG J E, LEE J S. Selective modification of block copolymers as proton exchange membranes [J]. Electrochimica Acta, 2004, 50(2): 617-620.
KIM B, KIM J, JUNG B. Morphology and transport properties of protons and methanol through partially sulfonated block copolymers [J]. Journal of Membrane Science, 2005, 250(1/2): 175-182.
HWANG H Y, KOH H C, JI W R, et al. Preparation of sulfonated SEBS block copolymer membranes and their permeation properties [J]. Desalination, 2008, 233(1): 173-182.
KOTELYANSKII M J, WAGNER N J, PAULAITIS M E. Molecular dynamics simulation study of the mechanisms of water diffusion in a hydrated, amorphous polyamide [J]. Computational Theoretical Polymer Science, 1999, 9(3/4): 301-306.
KOLEV V, FREGER V. Molecular dynamics investigation of ion sorption and permeation in desalination membranes [J]. Journal of Physical Chemistry: B, 2015, 119(44): 14168-14179.
刘清芝, 杨登峰, 胡仰栋. 水和盐分子在反渗透膜内扩散过程的分子模拟 [J]. 高等学校化学学报, 2009, 30(3): 568-572.
LIU Qingzhi, YANG Dengfeng, HU Yangdong. Water and salts molecular simulation of diffusion process in reverse osmosis membrane [J]. Chemical Journal of Chinese Universities, 2009, 30(3): 568-572.
黄政宇, 周宁玉, 谢朝新, 等. 正渗透过程中的分子动力学模拟研究 [J]. 当代化工, 2017, 46(10): 2022-2025.
HUANG Zhengyu, ZHOU Ningyu, XIE Chaoxin, et al. Molecular dynamics simulation in the process of forward osmosis [J]. Contemporary Chemical Industry, 2017, 10: 2022-2025, 2030.
IZQUIERDO-GIL M A, BARRAGÁN V M, VILLALUENGA J P G, et al. Water uptake and salt transport through nafion cation-exchange membranes with different thicknesses [J]. Chemical Engineering Science, 2012, 72(16): 1-9.
GEISE G M, FREEMAN B D, PAUL D R. Characterization of a sulfonated pentablock copolymer for desalination applications [J]. Polymer, 2010, 51(24): 5815-5822.
SAGLE A C, JU H, FREEMAN B D, et al. PEG-based hydrogel membrane coatings [J]. Polymer, 2009, 50(3): 756-766.
NI L, MENG J, GEISE G M, et al. Water and salt transport properties of zwitterionic polymers film [J]. Journal of Membrane Science, 2015, 491: 73-81.
HUTH E, MUTHU S, RUFF L, et al. Feasibility assessment of pervaporation for desalinating high-salinity brines [J]. Journal of Water Reuse Desalination, 2014, 4(2): 109.
FAVRE I, MOCZYDLOWSKI E, SCHILD L. On the structural basis for ionic selectivity among Na+, K+, and Ca2+ in the voltage-gated sodium channel [J]. Biophysical Journal, 1996, 71(6): 3110-3125.
LIANG X, LU X, YU M, et al. Modification of nanoporous supported lyotropic liquid crystal polymer membranes by atomic layer deposition [J]. Journal of Membrane Science, 2010, 349(1): 1-5.
CHANG K, XUE T, GEISE G M. Increasing salt size selectivity in low water content polymers via polymer backbone dynamics [J]. Journal of Membrane Science, 2018, 552: 43-50.
XIE Z, HOANG M, DUONG T, et al. Solgel derived poly(vinyl alcohol)/maleic acid/silica hybrid membrane for desalination by pervaporation [J]. Journal of Membrane Science, 2011, 383(1/2): 96-103.
XIE Z, HOANG M, NG D, et al. Effect of heat treatment on pervaporation separation of aqueous salt solution using hybrid PVA/MA/TEOS membrane [J]. Separation Purification Technology, 2014, 127(6): 10-17.
LUO H, ABOKI J, JI Y, et al. Water and salt transport properties of triptycene-containing sulfonated polysulfone materials for desalination membrane applications [J]. ACS Appl Mater Interfaces, 2018, 10(4): 4102-4112.
QUIÑONES-BOLAÑOS E, ZHOU H, SOUNDARARAJAN R, et al. Water and solute transport in pervaporation hydrophilic membranes to reclaim contaminated water for micro-irrigation [J]. Journal of Membrane Science, 2005, 252(1): 19-28.
KAI-SHIUN C, YI-CHUN C, TZU-HUAI Y, et al. Free volume and alcohol transport properties of PDMS membranes: insights of nano-structure and interfacial affinity from molecular modeling [J]. Journal of Membrane Science, 2012, 417/418(11): 119-130.
KHODAPARAST-KAZEROONIAN F, AMJAD-IRANAGH S, MODARRESS H. Molecular dynamics simulation study of carboxylated and sulfonated poly(arylene ether sulfone)membranes for fuel cell applications [J]. International Journal of Hydrogen Energy, 2015, 40(45): 15690-15703.
0
浏览量
5
下载量
1
CSCD
关联资源
相关文章
相关作者
相关机构
京公网安备11010802024621