College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China.
College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China.
J Colloid Interface Sci. 2020 Jul 15;572:114-121. doi: 10.1016/j.jcis.2020.03.087. Epub 2020 Mar 24.
A major issue hindering development of thin film nanocomposite (TFN) nanofiltration (NF) membrane is the interfacial defects induced by nanomaterial aggregation in top layer. Although various nanomaterials surface modification strategies have been developed to eliminate the interfacial defects, they usually involve extra modification steps and complex post-treatments. Inspired by the substrate-independent coating ability of tannic acid (TA) and the fact that the phenolic hydroxyl groups in TA can react with acyl chloride group in trimesoyl chloride, a TA coating solution containing TiO nanoparticles was used as an aqueous phase of interfacial polymerization to prepare interfacial modified TFN NF membranes in this study. Surface modification of TiO nanoparticles and interfacial polymerization can be carried out in a single step without any extra pre-modification step. It was found that the TA coating on TiO nanoparticles surface could decrease TiO aggregations and enhance interfacial compatibility between TiO and polyester matrix. The TFN NF membrane prepared at a TiO loading of 0.020 wt% exhibited a pure water flux of 28.8 L m h (284% higher than that of the controlled TFC membrane), and possessed enhanced NaCl and NaSO rejections of 57.9% and 94.6%, respectively, breaking through the trade-off between permeability and selectivity.
阻碍薄膜纳米复合（TFN）纳滤（NF）膜发展的一个主要问题是纳米材料在顶层聚集引起的界面缺陷。尽管已经开发了各种纳米材料表面改性策略来消除界面缺陷，但它们通常涉及额外的改性步骤和复杂的后处理。受单宁酸（TA）的基底独立涂层能力的启发，以及 TA 中的酚羟基可以与均苯三甲酰氯中的酰氯基团反应的事实，本研究中使用含有 TiO 纳米颗粒的 TA 涂层溶液作为界面聚合的水相，制备界面改性 TFN NF 膜。TiO 纳米颗粒的表面改性和界面聚合可以一步完成，无需任何额外的预改性步骤。研究发现，TiO 纳米颗粒表面的 TA 涂层可以减少 TiO 聚集并增强 TiO 和聚酯基体之间的界面相容性。在 TiO 负载量为 0.020wt%的情况下制备的 TFN NF 膜纯水通量为 28.8L·m-2·h-1（比对照的 TFC 膜高 284%），并且具有增强的 NaCl 和 Na2SO4 截留率，分别为 57.9%和 94.6%，突破了渗透性和选择性之间的权衡。
