Abstract:

Water shortage has become a global problem. Membrane distillation (MD) is widely used in seawater desalination and high-salt wastewater treatment due to its advantages. However, membrane wetting, membrane contamination and other problems still hinder the large-scale application of MD technology. In recent years, the omniphobic membrane can repel all kinds of liquids, and greatly improve the permeability, pollution resistance and stability of MD. In this work, the basic principles of anti-wetting and anti-pollution of omniphobic membranes are reviewed from the aspects of surface roughness, surface free energy, contact angle and liquid entry pressure, in the framework of membrane distillation application process. The preparation process of omniphobic membrane was summarized from the two basic steps of re-entrant rough surface construction and fluorination, and the potential application fields of omniphobic membrane were summarized. Finally, the challenges and future research directions of omniphobic membranes were discussed. This review had important guides for the structure design, preparation and application of polymer membranes for MD.

Key words: membrane distillation, omniphobic membrane, anti-wetting, anti-pollution

摘要：

水资源短缺成为全球共同面临的问题，膜蒸馏法（MD）凭借其优点被广泛应用于海水淡化和高含盐废水处理。然而，膜浸润、膜污染等问题仍然阻碍着膜蒸馏技术的大规模应用。近年来，全疏膜可以排斥各种液体，极大地提高了膜蒸馏的渗透性能、抗污染性能和稳定性能。本文在面向膜蒸馏应用过程的理论框架内，从膜的表面粗糙度、表面自由能、接触角以及液体进入压力等方面综述了全疏膜抗浸润、抗污染的基本原理。从可重入粗糙表面的构筑和氟化两个基本步骤总结了全疏膜的制备过程，概括了全疏膜目前潜在的应用领域。最后对全疏膜面临的挑战和未来研究方向进行了研讨。本文对膜蒸馏过程中聚合物膜结构的设计、制备及应用过程具有重要的指导意义。

关键词: 膜蒸馏, 全疏膜, 抗浸润, 抗污染