Polyethersulfone (PES)/quaternary ammonium polysulfone (QAPSf) blend ultrafiltration (UF) membranes with positive charge were fabricated by nonsolvent induced phase separation (NIPS) for use in dye and salt selective separation. QAPSf was synthesized by nucleophilic substitution with chloromethylated polysulfone (CMPSf). The effect of the PES/QAPSf mass ratio on the morphology and performance of blend UF membranes were studied. The membranes' zeta potentials gradually changed from negative to positive with decreases in the PES/QAPSf mass ratio. At PES/QAPSf mass ratios of 30:70 and 10:90, the zeta potentials of the membranes reached +1.8 mV and + 5.9 mV, respectively. Additionally, the contact angles of the membranes decreased from 74° to 52° as the QAPSf content increased from 0 wt% to 90 wt%. Furthermore, the membrane with a PES/QAPSf mass ratio of 30:70 showed a high water permeance (181.4 LMH bar⁻¹) and excellent dye and salt selective separation performance. The rejection ratios reached 99.1%, 87.8%, 99.6%, and 92.4% for dyes Congo red, methyl blue, Alixin blue 8GX, and basic blue 24, respectively, while those for salts Na₂SO₄, MgSO₄, MgCl₂, and NaCl were ≤ 10%. In addition, the PES/QAPSf membranes showed excellent antifouling performance and good operating stability with dye‐salt mixtures of various pHs and salt concentrations.

中文翻译：

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定制带正电荷的聚醚砜/季铵聚砜超滤膜用于染料和盐的选择性分离

通过非溶剂诱导相分离（NIPS）制备具有正电荷的聚醚砜（PES）/季铵聚砜（QAPSf）共混超滤（UF）膜，用于染料和盐的选择性分离。QAPSf是通过用氯甲基化聚砜（CMPSf）进行亲核取代合成的。研究了PES / QAPSf质量比对混合超滤膜的形貌和性能的影响。随着PES / QAPSf质量比的降低，膜的ζ电位逐渐从负变为正。在PES / QAPSf质量比为30:70和10:90时，膜的Zeta电位分别达到+1.8 mV和+ 5.9 mV。另外，随着QAPSf含量从0wt％增加到90wt％，膜的接触角从74°减小到52°。此外，^-1）和优异的染料和盐选择性分离性能。刚果红，甲基蓝，阿里信蓝8GX和碱性蓝24的拒染率分别达到99.1％，87.8％，99.6％和92.4％，而盐Na ₂ SO ₄，MgSO ₄，MgCl ₂， NaCl≤10％。此外，PES / QAPSf膜在各种pH和盐浓度的染料-盐混合物中均表现出出色的防污性能和良好的操作稳定性。