Abstract:

A novel nanocofitration membrane was prepared with SPES owning excellent performance by manual coating method. The tetrabutyl titanate and the TiO₂ nanoparticles were utilized to modify the separation performance. Meanwhile, the microstructure and permeability of NaCl and dye of the original and mixed matrix membrane were measured to evaluate the effect of the additive on the nanofiltration membrane performance. The permeate flux of the mixed matrix membrane fabricated by casting solution with a TBT concentration of 0.35% (mass) raised from 27.3 L·m^-2·h^-1 to 38.9 L·m^-2·h^-1, and the rejection of the NaCl of reduced from 91.2% to 82.5%. Compared with neat SPES membrane, modified membrane owned a bigger pore size, enlarging form 1.51 nm to 2.28 nm. Due to the addition loadings increasing, the nanoparticles obtained from gradually hydrolyzing could integrate, increased and formed further larger nanoparticles. The tetrabutyl titanate used as additive could improve the flux of the mixed matrix membrane and reduce the defect leaded by TiO₂ nanoparticles agglomeration. The butanol gained form the tetrabutyl titanate hydrolysis could also increase quantity of the pores on the neat SPES membrane skin layer and have an important influence on the separation performance of the mixed matrix membrane.

Key words: sulfonated polyether sulfone, nanoparticle, in-situ generated, nanofiltration, agglomeration

摘要：

采用涂覆法将磺化聚醚砜（SPES（浓度为0.7%（质量（的铸膜液制备成膜，并使用钛酸四丁酯（TBT（和TiO₂纳米颗粒作为添加剂来对比改善膜性能。通过对纳滤膜的微观结构表征，以及膜对NaCl与染料的分离性能等方面来分析其性能。当钛酸四丁酯的含量为0.35%（质量（时，膜的通量从27.3 L·m^-2·h^-1提升至38.9 L·m^-2·h^-1，而截留率则有91.2%降至82.5%。与纯SPES膜相比，改性纳滤膜的平均孔径更大，由1.51 nm增大为2.28 nm。TBT改性膜表面有TiO₂纳米颗粒形成，而且随着TBT的浓度增大，颗粒逐渐增大，而直接添加TiO₂纳米颗粒的纳滤膜的表面呈现明显的团聚现象。使用钛酸四丁酯代替TiO₂纳米颗粒作为添加剂，在增加膜通量的同时也能降低纳米颗粒团聚而导致的膜缺陷。由钛酸四丁酯水解生成的正丁醇的致孔作用对膜的性能具有很大的影响。

关键词: 磺化聚醚砜, 纳米粒子, 原位生成, 纳滤, 团聚