Membrane fouling, essentially originated from the interactions between foulant and membrane surface, is a big obstacle to use membrane distillation (MD) for ionic liquid recycling from its aqueous solution. By applying the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) approach and surface element integration method, this study mainly investigated the fouling behavior of three kinds of hydrophobic membranes during the vacuum MD (VMD) separation of 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) solutions. Effects of membrane surface chemical properties (e.g. elemental composition and zeta potential), membrane surface morphology (e.g. roughness), and [Bmim]Cl concentration on the interaction energy between [Bmim]Cl and membrane surface were studied. The results showed that the Lifshitz-van der Waals (LW) and electrostatic interaction (EL) components were positive (repulsion), while the acid-base (AB) interaction component was negative (attraction). Roughening membrane surface significantly decreased the interaction energy barrier, indicating a greater risk of being fouled. Even so, membrane surface chemical properties had more important impact on membrane fouling than surface morphology. Energy barrier would be also reduced when [Bmim]Cl concentration increased, signifying a severer membrane fouling potential in a concentration process. These results were expected to help to understand ILs-fouling mechanism in VMD process and guide the selection and fabrication of promising membrane for ILs recovery.

膜结垢主要源于污垢与膜表面之间的相互作用，这是使用膜蒸馏（MD）从其水溶液中回收离子液体的一大障碍。通过应用扩展的Derjaguin-Landau-Verwey-Overbeek（XDLVO）方法和表面元素整合方法，本研究主要研究了在1-MDT-3-甲基咪唑鎓真空MD（VMD）分离过程中三种疏水膜的结垢行为氯化物（[Bmim] Cl）溶液。研究了膜表面化学性质（例如元素组成和ζ电位），膜表面形态（例如粗糙度）和[Bmim] Cl浓度对[Bmim] Cl和膜表面之间相互作用能的影响。结果表明，Lifshitz-van der Waals（LW）和静电相互作用（EL）成分为正（排斥），而酸碱（AB）相互作用成分为负（吸引力）。粗糙的膜表面显着降低了相互作用能垒，表明被污染的风险更大。即使这样，膜表面化学性质对膜结垢的影响也比表面形态更重要。当[Bmim] Cl浓度增加时，能垒也将减少，这表明在浓缩过程中更严重的膜污染可能性。这些结果有望帮助理解VMD过程中的ILs结垢机理，并指导ILs回收的有前途的膜的选择和制造。而酸碱（AB）相互作用成分为负（吸引力）。粗糙的膜表面显着降低了相互作用能垒，表明被污染的风险更大。即使这样，膜表面化学性质对膜结垢的影响也比表面形态更重要。当[Bmim] Cl浓度增加时，能垒也将减少，这表明在浓缩过程中更严重的膜污染可能性。这些结果有望帮助理解VMD过程中的ILs结垢机理，并指导ILs回收的有前途的膜的选择和制造。而酸碱（AB）相互作用成分为负（吸引力）。粗糙的膜表面显着降低了相互作用能垒，表明被污染的风险更大。即便如此，膜表面化学性质对膜结垢的影响比表面形态更重要。当[Bmim] Cl浓度增加时，能垒也将减少，这表明在浓缩过程中更严重的膜污染可能性。这些结果有望帮助理解VMD过程中的ILs结垢机理，并指导ILs回收的有前途的膜的选择和制造。膜表面化学性质对膜结垢的影响比表面形态更重要。当[Bmim] Cl浓度增加时，能垒也将减少，这表明在浓缩过程中更严重的膜污染可能性。这些结果有望帮助理解VMD过程中的ILs结垢机理，并指导ILs回收的有前途的膜的选择和制造。膜表面化学性质对膜结垢的影响比表面形态更重要。当[Bmim] Cl浓度增加时，能垒也将减少，这表明在浓缩过程中更严重的膜污染可能性。这些结果有望帮助理解VMD过程中的ILs结垢机理，并指导ILs回收的有前途的膜的选择和制造。