“共价”型全疏/滑移表面构建及膜蒸馏性能研究  

Engineering a covalently constructed omniphobic/slippery membrane for high-performance membrane distillation

作　　者：李鹏 李猛 薛宇轩[2] 张庆五 陈晓玲 张轩 LI Peng;LI Meng;XUE Yucuan;ZHANG Qingwu;CHEN Xiaoling;ZHANG Xuan(Nanjing Water Group Co.,Ltd,Nanjing 210002,China;Key Laboratory of New Membrane Materials Ministry of Industry and Information Technology,Nanjing University of Science&.Technology,Nanjing 210094,China)

机构地区：[1]南京市水务集团有限公司,南京210002 [2]新型膜材料工信部重点实验室,南京理工大学,南京210094

出　　处：《膜科学与技术》2024年第1期27-36,共10页Membrane Science and Technology

基　　金：中央高校基本科研业务费专项资金项目(30923010905);企业横向合作项目(南京水务集团有限公司);江苏省自然科学基金青年项目(BK20210359);国家自然科学基金青年项目(52100046)。

摘　　要：由于孔隙润湿、矿物结垢或结构不稳定等引起的膜功能层失效问题是膜蒸馏(MD)技术的关键挑战,严重影响其长期运行稳定性.本文提出一种“全共价”接枝修饰的方法,制备具有优异MD性能的全疏/滑移膜蒸馏膜材料.具体而言,通过使用聚多巴胺型插层将纳米硅球共价键合在聚偏氟乙烯(PVDF)膜表面,并采用巯基-烯烃点击化学进行直接表面氟化改性.通过接触角测试,发现所制备的PDA/PVDF-C膜具有超高的静态水接触角(163.5°±0.9°)和极低的滚动角(5.6°±1.2°).在不同表面张力液体的侵蚀作用下,该膜均未出现膜孔的润湿现象,体现出优异的抗润湿性能.由于该膜表面特殊的全疏/滑移特性,该膜能够持久并稳定地处理含有表面活性剂的高盐卤水,延缓石膏垢的形成,运行性能显著优于商用疏水膜.该膜初始通量约为23.5 L/(m^(2)·h),运行前后始终保持对盐高达99%的截留.本研究提供了一种新颖而有效的方法开发“全共价”型MD膜,该膜具有优异的抗润湿、抗无机结垢以及结构稳定性,可用于高盐废水的资源化处理.The functional loss of membranes caused by pore wetting,mineral scaling,or structural instability is a critical challenge in membrane distillation(MD),severely impacting its long-term operational stability.In light of this,we provide a novel strategy to fabricate an omniphobic/slippery MD membrane via"covalent"grafting modification.Specifically,spherical silica nanoparticles were covalently bonded to the surfaces of polyvinylidene fluoride(PVDF)membranes using polydopamine(PDA)interlayer,followed by direct surface fluorination through thiol-ene click chemistry.Contact angle(CA)measurements reveal that the resulting membrane(PDA/PVDF-C)exhibits an ultrahigh water contact angle(163.5°±0.9°)and low sliding angle(5.6°±1.2°).Besides,the membrane shows excellent wetting resistance toward various liquids with low surface tension surface tension liquids,and outstanding anti-wetting properties for the short-term treatment of high-salinity brines containing surfactants.Due to its unique omniphobic/slippery characteristics,the membrane can durably and stably handle high-salinity brines containing surfactants,delaying the formation of gypsum scale.The membrane exhibits an initial flux of approximately 23.5 L/(m^(2)·h)and maintains a salt rejection of up to 99% during the whole operation.Overall,this study presents a novel and effective approach for fabricating high-performance membrane distillation(MD)membranes with high performance even under harsh operating conditions.

关 键 词：膜蒸馏 全疏/滑移 润湿 结垢 高盐水 

分 类 号：TQ028.8[化学工程]