Covalent organic frameworks embedded membrane via acetic-acid-catalyzed interfacial polymerization for dyes separation: Enhanced permeability and selectivity
Covalent organic frameworks embedded membrane via acetic-acid-catalyzed interfacial polymerization for dyes separation: Enhanced permeability and selectivity
复制标题
通过乙酸催化界面聚合的共价有机框架嵌入膜用于染料分离：增强的渗透性和选择性
DOI：
10.1016/j.chemosphere.2020.127580
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发表时间：
2020-12-01
期刊：
影响因子：
8.8
通讯作者：
Xia, Shengji
中科院分区：
文献类型：
--
作者：
Wu, Chao;Wang, Xiaoping;Xia, Shengji
随着人们对高水质要求的不断提高，膜过滤技术以其占地面积小、化学品用量少、性能稳定等优点在水处理中发挥着越来越重要的作用。然而，固有的渗透选择性权衡仍然是制约膜分离广泛应用的一个重要障碍。通过在膜中掺入纳米颗粒进行亲水性改性被认为是在保持选择性的同时提高渗透率的有效方法。然而，纳米颗粒的团聚往往导致改性膜的不均匀性。本研究首先采用醋酸催化原位合成的方法制备了具有分离共价有机骨架（COF）颗粒的杂化膜，并将其均匀嵌入膜表面孔中。由于COFs中含有丰富的亲水性化学基团和可调节的分子运输通道，改性膜的水通量提高了近两倍(约200 L m（-2).h(-1)）。Bar)比原始膜，同时增强排斥水污染物（即染料）。此外，COF的纯有机结构改善了混合膜的聚合物-填料相互作用，从而降低了泄漏的风险。因此，混合膜在长期操作和不同pH条件下也表现出较高的稳定性，这使其在未来的膜应用中具有前景。(C) 2020 Elsevier Ltd.版权所有。
With the increasing demand of high water-quality, membrane filtration technologies are playing further important roles in water treatment owing to their small footprints, reduced use of chemicals and stable performances. However, the inherent permeability-selectivity trade-off is still a significant obstacle restricting the broad applications of membrane separation. Hydrophilic modification via doping nanoparticles into membranes is considered an effective solution to improve the permeability while maintaining selectivity. However, agglomeration of nanoparticles often results in inhomogeneity of the modified membranes. In this study, hybrid membranes with separated covalent organic framework (COF) particles that were uniformly embedded in the membrane surface pores were firstly fabricated via acetic-acid-catalyzed in situ synthesis. Owing to the ample hydrophilic chemical groups and tunable molecular transport channels in COFs, the modified membranes yielded almost twice higher water flux (about 200 L m(-2).h(-1).bar) than the pristine membranes with simultaneously enhanced rejection of water pollutants (i.e., dyes). In addition, the pure organic structure of COF improves the polymer-filler interaction of the mixed film, thereby reducing the risk of leakage. Therefore, the hybrid membranes also exhibited relatively high stability in long-term operations and different pH conditions, which makes them promising candidates in future membrane applications. (C) 2020 Elsevier Ltd. All rights reserved.