State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
ACS Appl Mater Interfaces. 2020 Aug 19;12(33):37515-37526. doi: 10.1021/acsami.0c06037. Epub 2020 Aug 6.
We report a new robust and green facile platform for nonoxidizing chemical grafting to simultaneously improve antifouling and antibacterial properties of thin film composite (TFC) polyamide (PA) reverse osmosis (RO) membranes. In this work, alginate dialdehyde (ADA) was used as a green platform to graft chlorhexidine (CH), a nonoxidizing chemical, on TFC-RO membrane surface. A synergistic effect due to ADA and CH grafting was revealed. The modified membrane surfaces were characterized using XPS, FT-IR, AFM, SEM-EDS, contact angle, and zeta potential analysis. A simple two-step Schiff base reaction was performed. Improved salt rejection performances were observed for the grafted PA membranes at the expense of negligible flux drop for the CH-ADA-PA membranes (38 to 42 L m h) compared with the pristine PA membrane (45 L m h). All the CH-ADA-PA membranes had excellent antibacterial activity against along with a highly superior resistance to the formation of biofilms. Organic fouling behaviors with a protein (bovine serum albumin, BSA) and a surfactant (dodecyl trimethylammonium bromide, DTAB) were investigated as typical foulants for the grafted PA membranes. The results indicated that the CH-ADA-PA membranes showed the best antifouling performance followed by the ADA-PA membranes, the pristine membrane being the most inferior. Hence, these results pave the way for a new robust and green bioinspired route for practical application in RO membrane fouling control.
我们报告了一种新的稳健且绿色的简便平台，用于非氧化化学接枝，以同时提高薄膜复合（TFC）聚酰胺（PA）反渗透（RO）膜的抗污和抗菌性能。在这项工作中，海藻酸钠二醛（ADA）被用作绿色平台，将非氧化化学物质洗必泰（CH）接枝到 TFC-RO 膜表面。由于 ADA 和 CH 接枝的协同作用，揭示了协同作用。使用 XPS、FT-IR、AFM、SEM-EDS、接触角和 zeta 电位分析对改性膜表面进行了表征。进行了简单的两步席夫碱反应。与原始 PA 膜（45 L m h）相比，接枝 PA 膜的盐截留性能得到了改善，而通量下降可忽略不计（38 至 42 L m h）。所有 CH-ADA-PA 膜对具有出色的抗菌活性，并且对生物膜的形成具有高度优越的抵抗力。用蛋白质（牛血清白蛋白，BSA）和表面活性剂（十二烷基三甲基溴化铵，DTAB）作为典型的污染物研究了接枝 PA 膜的有机污染行为。结果表明，CH-ADA-PA 膜表现出最佳的抗污性能，其次是 ADA-PA 膜，原始膜的性能最差。因此，这些结果为 RO 膜污染控制的实际应用铺平了一条新的稳健且绿色的仿生途径。
