Novel Thin-Film Composite Tri-Bore Hollow Fiber Membrane Fabrication for Forward Osmosis

摘要

Hollow fiber membrane with the multi-bore configuration has attracted much attention credit to its ease of module potting and improved mechanical stability. The traditional multi-bore hollow fiber consists of seven or three bore channels and a round shape outer geometry. In this work, we have developed novel tri-bore thin-film composite (TFC) hollow fiber (HF) membranes for forward osmosis (FO) processes by employing a specially designed tri-bore blossom spinneret. The resultant hollow fibers exhibit evenly-distributed three inner bores with an either round or triangle outer geometry. The newly developed triangle tri-bore hollow fibers have impressive mechanical strength with enhanced permeation properties better than the round ones. It is hypothesized that the combined effects of fast phase inversion rate, die swell effect and stretching force during nascent fiber spinning are responsible for the formation of this unique membrane geometry.