关键词: 膜蒸馏, 特殊浸润性, 膜污染, 超疏水, 膜结垢

Abstract:

Membrane distillation technology has broad application space in fields of hypersaline wastewater treatment, high-value salt recovery and freshwater extraction. Until now, membrane distillation technology has not been widely promoted and applied yet for various reasons, among which membrane fouling is particularly prominent. Special wettable membrane has been recognized as an effective way to alleviate fouling in membrane distillation. Therefore, this article mainly reviewed the research progress on the antifouling characteristics of special wettable porous membranes from several aspects, e.g. the theoretical models of special wettable surfaces, membrane preparation and antifouling characteristics. Firstly, a brief introduction was given to membrane distillation technology and the types and processes of membrane fouling in membrane distillation, while the research hotspots and publications related to membrane distillation and membrane fouling in the past five years were discussed. Secondly, the fabrication principles of special wettable surfaces were systematically elaborated based on the Young model, Wenzel model and Cassie-Baster model. The design, fabrication and antifouling characteristics of special wettable porous membranes were illustrated with examples. Finally, the difficulties and challenges for the application of special wettable porous membrane in antifouling membrane distillation were raised, including complex preparation processes, fragile micro/nano structures, lack of low surface energy materials and inconsistent evaluation standards. The development of special wettable porous membranes with low toxicity, low cost, broad-spectrum antifouling ability, and acid and alkali resistance would become a key research direction.

Key words: membrane distillation, special wettability, membrane fouling, superhydrophobic, membrane scaling