Membrane-based filtration offers many benefits like lower energy consumption and operating cost for separation in harsh solvents. In particular, such membranes need to have high nanofiltration separation efficiency and high resistance to organic solvents. Unfortunately, the common thin film composite (TFC) - based organic solvent nanofiltration membranes often give low solvent permeance due to the dense skin layer atop the substrate. To address this, we fabricated a covalent organic framework (COF) - incorporated TFC membrane through the in-situ formation of benzene-1,3,5-tricarboxaldehyde (TFB) and graphene oxide (GO) in p-Cymene, a less toxic solvent, with p-Phenylenediamine (PPD) in aqueous phase via interfacial polymerization. The PES-COF-GO membranes exhibited optimal solvent permeance and separation efficiency at an intermediate 0.8wt% GO, which gave the highest water permeance of 16.2L/m² h bar and a molecular weight cut-off (MWCO) of around 325 gmol^-1. In addition, the crosslinked GO-COF layer endowed the membrane with chemical stability in non-polar solvents. The mechanical strength of PES-COF-GO membrane was also improved due to the COF-GO layer atop the PES substrate making the surface tighter and mechanically stronger.

基于膜的过滤具有许多优点，例如在苛刻溶剂中分离的能耗和运营成本较低。特别地，此类膜需要具有高纳滤分离效率和对有机溶剂的高耐受性。不幸的是，基于普通薄膜复合材料 (TFC) 的有机溶剂纳滤膜通常由于基材顶部的致密表层而具有较低的溶剂渗透性。为了解决这个问题，我们制造了一种共价有机框架(COF) - 通过原位形成苯-1,3,5-三甲醛 (TFB) 和氧化石墨烯 (GO) 在p -Cymene 中结合 TFC 膜，一种毒性较小的溶剂，与p-通过界面聚合在水相中的苯二胺 (PPD)。PES-COF-GO 膜在中间 0.8wt% GO 时表现出最佳的溶剂渗透性和分离效率，最高水渗透率为 16.2L/m ²  h bar，截留分子量 (MWCO) 约为 325 gmol ^-1 。此外，交联的 GO-COF 层赋予膜在非极性溶剂中的化学稳定性。PES-COF-GO 膜的机械强度也得到了提高，因为 PES 基底上的 COF-GO 层使表面更紧密且机械强度更高。