(722a) Thermally and Chemically-Treated Polyacrylonitrile Hollow Fiber Membranes for Organic Solvent Nanofiltration

Polyacrylonitrile (PAN) hollow fiber membranes suitable for organic solvent nanofiltration (OSN) were fabricated. To obtain pristine ultrafiltration-level hollow fibers possessing the desired morphology of a sponge-like cross-section with minimal macrovoids, the dope composition was adjusted while hollow fiber spinning parameters such as the take-up speed were changed. Hydrazine monohydrate was subsequently used for the cross-linking process and the effects of cross-linking duration on the hollow fibers’ separation performances were investigated. X-ray photoelectron spectroscopy was used to provide insight into the possible reactions that might have occurred during the modification process and generally indicated the successful cross-linking of the PAN membranes. Using ethanol and dyes as model feed solutions, the hollow fiber membranes were subjected to OSN tests. With this straightforward and effectual modification, the PAN hollow fiber membranes were able to achieve a pure ethanol permeance of 2.32 L m^-2 h^-1 bar^-1 and a remarkable Remazol Brilliant Blue R (M_w 626.54 g mol^-1) rejection of more than 99.9%. Considering the relative simplicity of fabrication, these PAN membranes represent a noteworthy advancement in the use of hollow fiber membranes for OSN with potential applications in larger-scale operations.