Preparation and characterization of positively charged polyamide composite nanofiltration hollow fiber membrane for lithium and magnesium separation
Preparation and characterization of positively charged polyamide composite nanofiltration hollow fiber membrane for lithium and magnesium separation
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DOI：
10.1016/j.desal.2015.04.027
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发表时间：
2015-08-03
期刊：
影响因子：
9.9
通讯作者：
Cui, Zhenyu
中科院分区：
文献类型：
--
作者：
Li, Xianhui;Zhang, Chunjin;Cui, Zhenyu
以聚丙烯腈（PAN）中空纤维超滤膜为基体，通过界面聚合法制备了1，4-二（3-氨丙基）哌嗪（DAPP）和均苯三甲酰氯（TMC）荷正电的聚酰胺复合中空纤维纳滤（NF）膜，用于锂和镁的分离。采用ATR-FTIR、XPS、SEM、AFM和Zeta电位分析仪对复合膜的化学结构、形貌和表面电荷进行了表征。在0.3MPa的操作压力下用各种盐的水溶液（2000 ppm）测试复合膜的性能。结果表明，膜性能与水相中单体含量的变化有关，而与有机相中单体含量的变化无关。膜的脱盐率为MgCl_2> MgSO_4> NaCl >= LiCl。MgCl_2和LiCl的截留率之差达到47.5%。ζ电位测量表明，所得膜的表面在pH值低于9.5时带正电荷。此外，在2.0g/L MgCl 2和LiCl混合液中，Mg 2 +/Li+的质量比由初始的20：1下降到经复合膜过滤后的7.7：1。(C)2015爱思唯尔B. V.保留所有权利。
A positively charged polyamide composite nanofiltration (NF) hollow fiber membrane for lithium and magnesium separation was fabricated by the interfacial polymerization of 1,4-Bis(3-aminopropyl)piperazine (DAPP) and trimesoyl chloride (TMC) on the polyacrylonitrile (PAN) ultrafiltration hollow fiber membrane. The chemical structure, morphology and surface charge of the composite membrane were characterized by using ATR-FTIR, XPS, SEM, AFM and zeta potential analyzer. The performance of the composite membrane was tested with various salts in aqueous solution (2000 ppm) at the operating pressure of 0.3 MPa. The results showed that the membrane performance was related to the changes of the monomer content in the aqueous phase rather than that in the organic phase. Furthermore, the salt rejection order of the membrane was MgCl2 > MgSO4 > NaCl >= LiCl. The difference between the rejections of MgCl2 and LiCl reached to 47.5%. The zeta potential measurements indicated that the surface of the resultant membrane was positively charged at pH values below 9.5. Moreover, the mass ratio of Mg2+/Li+ decreased from initial 20:1 in the feed of 2.0 g/L MgCl2 and LiCl mixture to 7.7:1 in the permeate after the filtration by the composite membrane. (C) 2015 Elsevier B.V. All rights reserved.