A novel nanofiltration (NF) membrane with a positively and negatively dual-charged layer was finely designed in this study. The membrane was prepared by co-deposition of 4-tert-butylpyrocatechol (TBC) and polyethyleneimine (PEI) and electrostatic interaction to assemble positively and negatively charged functional layers on a substrate which is polyamide (PA)-based NF membrane. The NF membrane achieved excellent retention capacity through the combined effects of Donnan repulsion and electrostatic field trapping. The prepared membrane had a dense but thin surface layer with an average pore size of 0.84 nm, enabling an improved membrane flux of 8.66 L/(m·h·bar) and high rejection to divalent inorganic salt ions (93.56 % Mg, 99.56 % SO). The membrane was used to treat acid mine drainage (AMD) and achieved an excellent retention capacity for ions in AMD (93.25 % Mg, 91.58 % Ca, 94.22 % Mn, 95.96 % SO), meeting industrial wastewater discharge standards. In addition, the NF membrane demonstrated good anti-fouling performance during the AMD treatment and significant potential for environmental remediation applications.

中文翻译：

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一种具有双电荷层的新型纳滤膜，可同时去除酸性矿山排水中的阴离子和阳离子


本研究精心设计了一种具有正负双电荷层的新型纳滤（NF）膜。该膜是通过共沉积 4-叔丁基邻苯二酚 (TBC) 和聚乙烯亚胺 (PEI) 并通过静电相互作用在聚酰胺 (PA) 基纳滤膜基底上组装带正电和带负电的功能层来制备的。通过唐南斥力和静电场捕获的综合作用，纳滤膜实现了优异的截留能力。制备的膜具有致密但薄的表面层，平均孔径为0.84 nm，膜通量提高到8.66 L/(m·h·bar)，并且对二价无机盐离子具有高截留率（93.56 % Mg，99.56 %所以）。该膜用于处理酸性矿山废水（AMD），对AMD中的离子（93.25% Mg、91.58% Ca、94.22% Mn、95.96% SO）具有优异的截留能力，满足工业废水排放标准。此外，NF膜在AMD处理过程中表现出良好的防污性能，在环境修复应用中具有巨大的潜力。