Membrane fouling is inevitable during nanofiltration of industrial liquids. Understanding the influence of membrane physicochemical properties and structures on its antifouling performance can guide the membrane selection and preparation. In this study, the antifouling ability of three commercial nanofiltration membranes (NF270, NFA4 and DK) was assessed using organic foulants with different charge patterns. Besides, the pristine and fouled membranes were systematically characterized. The results showed that although the negatively charged polyamide membrane had a strong antifouling ability to negatively charged substances, the fouling extent was still affected by the membrane pore size distribution. For the small foulants with positive charge, driven by electrostatic adsorption effect, they were easier to be anchored on the membrane surface with higher roughness. Due to the synergistic effect of membrane charge and roughness, the flux decay ratio increased from 5.1% for the NFA4 to 63.1% for the DK with more negative charge and highest roughness. Moreover, according to FTIR, XPS deep profiling and SEM cross-section analysis, it was found that the structure of the separation layer (e.g., single/double layer or cross-linking density in horizontal/longitudinal) closely related to its antifouling performance. Therefore, a nanofiltration membrane with narrow pore size distribution, moderate charge, smooth and hydrophilic surface is more prone to resist organic fouling formation. The outcomes of the work also offer several strategies to prepare antifouling nanofiltration membranes.

在工业液体的纳滤过程中，膜污染是不可避免的。了解膜的理化性质和结构对其防污性能的影响可以指导膜的选择和制备。在这项研究中，使用具有不同电荷模式的有机污染物评估了三种商用纳滤膜（NF270、NFA4 和 DK）的防污能力。此外，系统地表征了原始膜和污染膜。结果表明，虽然带负电荷的聚酰胺膜对带负电荷的物质具有较强的抗污染能力，但污染程度仍受膜孔径分布的影响。对于带正电荷的小污染物，在静电吸附作用的驱动下，它们更容易锚定在具有较高粗糙度的膜表面上。由于膜电荷和粗糙度的协同作用，通量衰减率从 NFA4 的 5.1% 增加到负电荷更多和粗糙度最高的 DK 的 63.1%。此外，根据FTIR、XPS深剖面和SEM截面分析发现，分离层的结构（如单层/双层或水平/纵向的交联密度）与其防污性能密切相关。因此，孔径分布窄、电荷适中、表面光滑亲水的纳滤膜更容易抵抗有机污染的形成。这项工作的成果还提供了几种制备防污纳滤膜的策略。由于膜电荷和粗糙度的协同作用，通量衰减率从 NFA4 的 5.1% 增加到负电荷更多和粗糙度最高的 DK 的 63.1%。此外，根据FTIR、XPS深剖面和SEM截面分析发现，分离层的结构（如单层/双层或水平/纵向交联密度）与其防污性能密切相关。因此，孔径分布窄、电荷适中、表面光滑亲水的纳滤膜更容易抵抗有机污染的形成。这项工作的成果还提供了几种制备防污纳滤膜的策略。由于膜电荷和粗糙度的协同作用，通量衰减率从 NFA4 的 5.1% 增加到负电荷更多和粗糙度最高的 DK 的 63.1%。此外，根据FTIR、XPS深剖面和SEM截面分析发现，分离层的结构（如单层/双层或水平/纵向交联密度）与其防污性能密切相关。因此，孔径分布窄、电荷适中、表面光滑亲水的纳滤膜更容易抵抗有机污染的形成。这项工作的成果还提供了几种制备防污纳滤膜的策略。负电荷较多、粗糙度最高的 DK 为 1%。此外，根据FTIR、XPS深剖面和SEM截面分析发现，分离层的结构（如单层/双层或水平/纵向的交联密度）与其防污性能密切相关。因此，孔径分布窄、电荷适中、表面光滑亲水的纳滤膜更容易抵抗有机污染的形成。这项工作的成果还提供了几种制备防污纳滤膜的策略。负电荷较多、粗糙度最高的 DK 为 1%。此外，根据FTIR、XPS深剖面和SEM截面分析发现，分离层的结构（如单层/双层或水平/纵向的交联密度）与其防污性能密切相关。因此，孔径分布窄、电荷适中、表面光滑亲水的纳滤膜更容易抵抗有机污染的形成。这项工作的成果还提供了几种制备防污纳滤膜的策略。单/双层或横向/纵向交联密度）与其防污性能密切相关。因此，孔径分布窄、电荷适中、表面光滑亲水的纳滤膜更容易抵抗有机污染的形成。这项工作的成果还提供了几种制备防污纳滤膜的策略。单/双层或横向/纵向交联密度）与其防污性能密切相关。因此，孔径分布窄、电荷适中、表面光滑亲水的纳滤膜更容易抵抗有机污染的形成。这项工作的成果还提供了几种制备防污纳滤膜的策略。