A novel approach to fabricate macrovoid‐free and highly permeable PVDF hollow fiber membranes for membrane distillation

The commercial polypropylene (PP) and Teflon (PTFE) hollow fiber membranes commonly applied for membrane distillation process are associated with drawbacks that limit the highest achievable flux through process. These fibers are normally fabricated by melt spinning and sintering that makes it difficult to fabricate membranes with high porosity (higher than 70%) and high degree of pores interconnectivity. Therefore, it is of great interest to fabricate alternative membrane contactors such as PVDF hollow fibers through phase inversion processes that provide more freedom to optimize membrane properties. Some progress has been made in fabrication of these fibers recently; however, optimizing membrane properties in accordance with some specific applications is yet to be investigated. Before we address the objectives of this article, we briefly review the essential characteristics of an ideal hollow fiber membrane applied in membrane distillation (MD).

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