Abstract:
Supported membranes and mixed matrix membranes have a limitation of harming the mass transfer due to the incompatibility between the support layer or the matrix and the active components of the membrane. Self-standing membranes, which could structurally abandon the support layer, altogether avoid the adverse effect, thus greatly facilitating the transmembrane mass transfer process. However, the abandonment of the support layer also reduces the membrane\'s mechanical properties and formability. In this review, our emphasis will be on self-standing membranes within the realm of materials and separation engineering. We will explore the materials employed in the fabrication of self-standing membranes, highlighting their ability to simultaneously enhance membrane performance and promote self-standing characteristics. Additionally, we will delve into the diverse techniques utilized for crafting self-standing membranes, encompassing interfacial polymerization, filtration, solvent casting, Langmuir-Blodgett & layer-by-layer assembly, electrospinning, compression, etc. Throughout the discussion, the merits and drawbacks associated with each of these preparation methods were elucidated. We also provide a brief overview of the applications of self-standing membranes, including water purification, gas separation, organic solvent nanofiltration, electrochemistry, and membrane reactor, as well as a brief description of the general strategies for performance enhancement of self-standing membranes. Finally, the current status of self-standing membranes and the challenges they may encounter were discussed.
摘要:
由于支撑层或基质与膜的活性组分之间的不相容性,支撑膜和混合基质膜具有损害传质的限制。自立膜,这可能会在结构上放弃支撑层,完全避免不利影响,从而极大地促进了跨膜传质过程。然而,支撑层的废弃也降低了膜的机械性能和成形性。在这次审查中,我们的重点将是材料和分离工程领域内的自立膜。我们将探索用于制造自立膜的材料,突出了它们同时增强膜性能和促进自立特性的能力。此外,我们将深入研究用于制作自立膜的各种技术,包括界面聚合,过滤,溶剂浇铸,Langmuir-Blodgett和逐层组装,静电纺丝,压缩,等。在整个讨论过程中,阐明了这些制备方法的优缺点。我们还简要概述了自立膜的应用,包括水净化,气体分离,有机溶剂纳滤,电化学,和膜反应器,以及对自立膜性能增强的一般策略的简要描述。最后,讨论了自立膜的现状及其可能遇到的挑战。