Abstract

Patterned membranes prepared via spray-modified non -solvent induced phase separation (s-NIPS) have successfully shown enhanced fluxes and better fouling control, thanks to the increased surface area and high fluid shear at the membrane/feed interface. These novel membranes are now taken a step further by using them as support for interfacial polymerization (IP) to create thin-film composite (TFC) membranes with increased fluxes. The successful deposition of a dense polyamide top layer on a wave-patterned support (pattern height: similar to 100 mu m) is now demonstrated. Different methods were compared for the challenging removal of excess monomer above the grooved support surface. Spin-drying assisted IP (s-IP) led to the best membrane performance. Hence, s-IP was further optimized for patterned supports via systematic investigation of the effects on the membrane performance of monomer compositions, number of IP reactions, and properties of the patterned support. The micropatterned TFC membranes prepared via s -IP showed significantly higher permeance ( +280 %) than flat TFC membranes prepared via conventional IP without reduction in MgSO4 retentions (98.7 +/- 1.8 %), thanks to the corrugations and the modified IP procedure.

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