Polyacrylonitrile supported thin film composite hollow fiber membranes for forward osmosis

• Shell-side TFC hollow fiber for FO was fabricated. • Polyacrylonitrile was used as the support polymer material. • Different pore structures of fibers were considered by altering the fabrication technique. • Our best membrane exhibited a structural parameter of ~300 μm.

In this work, we investigated polyacrylonitrile supported TFC hollow fiber membranes for use in forward osmosis. The intrinsically hydrophilic PAN substrate material was used to mitigate ICP by ensuring wetting of the supporting structure. We also described a simple way to adjust the structure of the fibers in order to elucidate the structure– performance relationships of TFC hollow fiber membranes during osmosis. While exhibiting good osmotic performance overall, our best performing membrane exhibited one of the lowest structural parameter of TFC hollow fiber membranes reported in the open literature. Our thinnest membrane had a wall thickness of ~50 μm and was shown to have excellent performance when compared to the flat sheet counterparts and other shell-selective hollow fiber membranes reported in the literature. Acknowledgments We acknowledge funding from the U.S. Environmental Protection Agency (#R834872), the National Science Foundation (CBET #1160098), the 3M Nontenured Faculty Award, the Dupont Young Faculty Award, and the GE Graduate Fellowship for Innovation.