459680 Tri-Bore PVDF Hollow Fibers with a Super-Hydrophobic Coating for Membrane Distillation

Wednesday, November 16, 2016: 10:18 AM
Golden Gate 2 (Hilton San Francisco Union Square)
Jian Zuo, Tai-Shung Chung and Kangjia Lu, Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore

Membranes with good mechanical strength, high vapor flux and outstanding anti-wetting properties are essential for membrane distillation (MD) applications. In this work, porous polyvinylidene fluoride (PVDF) tri-bore hollow fiber membranes with super-hydrophobicity are developed to achieve these desired properties. The tri-bore hollow fiber offers better mechanical strength than the conventional single-bore fiber. To improve its anti-wetting properties, Teflon® AF 2400 is coated on the membrane surface. The effects of coating on membrane morphology, performance and anti-wetting properties have been thoroughly investigated. With an optimal coating condition (0.025 wt% of Teflon® AF 2400, 30 s), a super-hydrophobic surface with a contact angle of 151o is achieved. The resultant membrane shows an increase of 109% in liquid entry pressure (LEP) with a slight sacrifice of 21% in flux. Long term direct contact MD tests have confirmed that the Teflon® AF 2400 coated membrane has enhanced stability with an average flux of 21 kg m-2 h-1 and rejection of 99.99% at 60 C for desalination application.

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See more of this Session: Membrane Distillation and Membrane Contactors
See more of this Group/Topical: Separations Division