低浓度范围内盐浓度对纳滤膜截留性能的影响
作者:姜迪,徐异峰,陆国太,杨刚,邢卫红
单位: 南京工业大学 材料化学工程国家重点实验室,江苏 南京 210009
关键词: 纳滤膜;截留率;荷电密度;介电常数;模型
DOI号:
分类号: TQ028.8
出版年,卷(期):页码: 2017,37(1):64-68

摘要:
 采用Desal-DK有机纳滤膜分别对低浓度范围(1-50 mol/m3)的KCl、NaCl、Na2SO4、K2SO4、MgCl2水溶液进行纳滤实验,考察盐的浓度及类型对截留率的影响,结合道南细孔-介电DSPM-DE模型计算等效荷电密度(Xd),孔内介电常数(εp),采用DSPM模型计算等效膜孔半径(rp),研究不同类型盐的截留率变化和Xd、εp、rp的关系。结果表明:Na2SO4、K2SO4的截留率变化趋势和KCl、NaCl相同,随着盐浓度的增加而降低,其原因归结于随着浓度的增加|Xd|增加,电荷屏蔽作用增强,道南电势减弱;MgCl2的截留率随着盐浓度的增加而升高,原因是浓度的增加Mg2+与膜的羧基不断发生特性结合,|Xd|升高,εp降低,静电排斥作用变大和介电排斥作用增强的双重作用。
 Salt solutions(KCl, NaCl, Na2SO4, K2SO4, MgCl2) were filtrated with a commercially available DK nanofiltration membrane to evaluate effects of concentration and type of salt in the feed side on the membrane performance, The concentration of them was in the range from 1 to 50 mol/m3. The Donnan steric pore and dielectric exclusion(DSPM-DE) model and DSPM model was applied to calculate Volumetric membrane charge values, dielectric constant, and pore radius, to analyze the relationship between the parameters and rejection of salt. In the low concentration range, The results showed that the rejection of Na2SO4 and K2SO4 showed the same changing rule as the KCl and NaCl, the membrane charge density(|Xd|) increased when the concentration of salt solutions increased, the rejection decreased duo to charge screening. The rejection of MgCl2 increased with increasing of the concentration. the |Xd| of salt solution decreased first and then increased, duo to special combination of Mg2+ with carboxyl, The electrostatic repulsion and the dielectric exclusion influenced the rejection of MgCl2 together.

基金项目:
国家支撑计划,课题名称造纸达标尾水膜法处理工艺包设计与应用(2013BAE11B03)

作者简介:
第一作者简介:姜迪(1989—),男,河南夏邑人,硕士生,主要研究方向为膜分离;通讯作者,E-mail: yanggang@ njtech.edu.cn.

参考文献:
 [1] Labbez C, Fievet P. Retention of mineral salts by a polyamide nano?ltration membrane[J]. Separation and Puri?cation Technology, 2003, 30:47-55.
[2] Mazzoni C, Bandini S. On nano?ltration Desal-5 DK performances with calcium chloride–water solutions[J]. Separation and Puri?cation Technology, 2006, 52:232-240.
[3] Mazzoni C, Bruni L, Bandini S. Nanofiltration: Role of the Electrolyte and pH on Desal DK Performances[J]. industrial & engineering chemistry research, 2007, 46: 224-2262.
[4] Bowen W R, Welfoot J S, Williams P M. Linearized Transport Model for Nanofiltration: Development and Assessment[J]. AIChE Journal, 2002, 48: 760-773.
[5] Deon S, Escoda A, Fievet P. A transport model considering charge adsorption inside pores to describesalts rejection by nano?ltration membranes[J]. Chemical Engineering Science, 2011, 66: 2823-2832.
[6] 戚茂飞, 武海洋, 刘文强等. CaCl2对葡萄糖纳滤截留率的影响[J]. 南京工业大学学报:自然科学版, 2011, 33(4): 103-106.
[7] Schaep J, Vandecasteele C, WMohammad A W. Modelling the retention of ionic components for different nano?ltration membranes[J]. Separation and Puri?cation Technology, 2001, 22(3): 169-179.
[8] Hsich F H, Matsutura T, Souriajan S. Reverse osmosis separations of polyethylene glycols in dilute aqueous solutions using porous cellulose acetate membranes[J]. Journal of Applied Polymer Science, 1979, 23(2): 561-573.
[9] Nakao S., Kimura S. Analysis of solutes rejection in ultrafiltration[J]. Journal of Chemical Engineering of Japan, 1981, 14(1): 32-37.
[10] Bowen W. R., Mukhtar H. Characterization and prediction of separation performance of Nanofiltration membranes[J]. Journal of Membrane Science, 1996, 112(2): 263~274.
[11] Mohammada A W, Hilal N, Darwish N A. Prediction of permeate fluxes and rejections of highly concentrated salts in nanofiltration membranes[J]. Journal of Membrane Science, 2007, 289(1-2): 40-50.
[12] Koga Y, Katayanagi H, Davies J V, et al. The effects of chloride salts of some cations on the molecular organization of H2O: towards understanding the hofmeister series[J]. The Chemical Society of Japan, 2006, 79:1347-1354.
[13] Zhang Y J, Cremer P S. Interactions between macromolecules and ions: the Hofmeister series[J]. Current Opinion in Chemical Biology, 2006, 10:658-663.
[14] Bargeman G, Westerink J B, Miguez O G, et al. The effect of NaCl and glucose concentration on retentions for nano?ltration membranes processing concentrated solutions[J]. Separation and Puri?cation Technology, 2014, 134:46-57.
 

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