Defective Covalent Organic Frameworks Interlayer Modified Polyamide Nanofiltration Membrane for Selective Ion Sieving

作     者：Fang, Yin-Xin Xu, Zhen-Liang Xu, Sun-Jie 

作者机构：State Key Laboratory of Chemical Engineering Membrane Science and Engineering R&D Lab Chemical Engineering Research Center School of Chemical Engineering East China University of Science and Technology Shanghai200237 China School of Materials Science and Engineering East China University of Science and Technology Shanghai200237 China Shanghai Electronic Chemicals Innovation Institute East China University of Science and Technology Shanghai200237 China 

出 版 物：《SSRN》 

年 卷 期：2024年

核心收录：

主　　题：Nanofiltration 

摘      要：Generally, thin-film composite (TFC) membrane prepared via piperazine (PIP) and trimesoyl chloride (TMC) has a good rejection of Na2SO4, but the rejection of MgCl2 was not satisfactory. Herein, a defective covalent organic frameworks (COFs) interlayer is fabricated via interfacial polymerization (IP) method by changing the catalyst concentration. The effect of the COFs layer is modifying the pore size of polyamide (PA) layer to improve the rejection of divalent cation. The results shows that the pore size of PA layer decreases and the surface morphology of the membrane transfers from nodule to hybrid morphologies of ridge-and-valley’’ and nodule, indicating that the residual unreacted amine groups on the COFs interlayer have successfully reacted with the acyl chloride groups. Meanwhile, the optimal PIP/COF-A/PES membrane has high rejections of divalent ions (Na2SO4 of 98.3%, MgCl2 of 94.3%), and the membrane shows an excellent mono/divalent ions separation performance. Therefore, this work raises a novel method to prepare NF membrane by modifying the PA layer for the enhancement of divalent cation rejection. © 2024, The Authors. All rights reserved.