Abstract: High flux of polyethersulfone (PES) nanofiltration (NF) membrane was fabricated with triblock copolymer Pluronic F127 as additive using a special casting machine by phase inversion method for dye concentration and desalination. The effects of additive content in the casting solution, solvent evaporation temperature and evaporation time during membrane fabrication on the structure and performance of the PES NF membrane were examined, and the separation performance of the PES NF membrane for dyes at different operation pressure and temperature was investigated. The scanning microscopy observation, contact angle test, porosity data and protein adsorption test show that the pore structure of the membrane is improved, its porosity and antifouling performance are enhanced with the addition of Pluronic F127. Pure water flux, rejection and membrane surface pore size characterization indicate that with the Pluronic F127 content in the caste solution at 3%, the solvent evaporation temperature at 90℃ and the solvent evaporation time at 18 s, the fabricated membrane presents the best separation performance. The rejection of the PES NF membrane for Eriochrome Black T is 99%, with a flux of 110.2 L·m^-2·h^-1, while the rejection for NaCl is only 5.5% at 0.6 MPa. The desalination and purification experiment exhibits that the rejection for the dye remains over 99% throughout the whole experiment, indicating that the PES NF membranes could be successfully applied in the dye purification and desalination process.

Key words: nanofiltration, desalination, waste water, antifouling

摘要： 以聚醚砜（PES）为膜材料，以嵌段式聚醚 Pluronic F127为添加剂，利用特制刮膜设备通过相转化法制备出高通量PES/Pluronic F127复合纳滤膜，并将其用于染料的浓缩脱盐。研究了添加剂含量、溶剂蒸发温度和蒸发时间对膜结构和膜性能的影响，考察了不同操作压力和操作温度下膜对染料的分离性能。扫描电镜 （SEM）、接触角、孔隙率数据和蛋白吸附测试结果表明，Pluronic F127改善了膜孔结构，提高了孔隙率，并且显著提高了膜的抗污染性能。纯水通量、截留率以及膜表面孔径表征结果表明，当Pluronic F127含量为3%、溶剂蒸发温度为90℃、 蒸发时间为18 s时，膜的分离性能最佳。在0.6 MPa下该膜对低分子量染料的截留率可达99.9%，且通量达到110.2 L·m^-2·h^-1，对NaCl的截留率仅为5.5%。在12 h的染料浓缩脱盐中，膜对染料的通量维持在较高水平且截留率始终保持在99%左右，具有良好的稳定性和抗污染性。

关键词: 纳滤, 脱盐, 废水, 抗污染