Akbari Ahmad, Fakharshakeri Zahra, Mojallali Rostami Sayed Majid
Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan, Iran E-mail:
Water Sci Technol. 2016;73(4):776-89. doi: 10.2166/wst.2015.538.
In this paper, a novel positively charged membrane was prepared through interfacial polymerization technique between polyethyleneimine in aqueous phase and trimesoyl chloride in organic phase. Next, cross-linking of polyamide (PA) layer using ρ-xylylene dichloride (XDC) and glutaraldehyde (GA) was studied. The influences of cross-linking concentrations on the separation and permeation performance of membrane were also investigated. Membranes were characterized in terms of their chemical structure, the cross-sectional and surface morphologies, contact angles, molecular weight cut-off (MWCO) and effect of pH feed solution. The salt rejection sequence of CaCl2 >NaCl > Na2SO4 showed a positive charge at the membrane surface after cross-linking reaction. The MWCO of primary PA membrane decreased from 1,135 to 775 and 885 Da for XDC and GA, respectively. XDC membrane shows highest CaCl2 divalent cationic rejection (95.5%) and lowest water flux (21.1 L/m(2).h). This study illustrates a promising method for fabrication of positively charged membrane in cation separation.
本文通过水相中的聚乙烯亚胺与有机相中的均苯三甲酰氯之间的界面聚合技术制备了一种新型带正电荷的膜。接下来，研究了使用对二氯苄（XDC）和戊二醛（GA）对聚酰胺（PA）层进行交联。还研究了交联浓度对膜的分离和渗透性能的影响。通过膜的化学结构、横截面和表面形态、接触角、截留分子量（MWCO）以及进料溶液pH值的影响对膜进行了表征。交联反应后，CaCl2>NaCl>Na2SO4的盐截留顺序表明膜表面带正电荷。对于XDC和GA，初级PA膜的截留分子量分别从1135 Da降至775 Da和885 Da。XDC膜表现出最高的CaCl2二价阳离子截留率（95.5%）和最低的水通量（21.1 L/m²·h）。本研究说明了一种在阳离子分离中制备带正电荷膜的有前景的方法。
