Preparation of Hollow Fiber Membranes by Nonsolvent Induced Phase Separation along with Hydrogen Gas Formation Using a Single Orifice Spinneret

Abstract Traditional nonsolvent induced phase separation (NIPS) process for fabrication of hollow fiber membranes (HFMs) faces challenges, like design and manufacture of spinneret with two concentric orifices to provide parallel and continuous feed of polymer solution and bore fluid at specific rates. These factors limit the use of traditional technique to produce HFMs. Here, a new direct spinning method for fabricating HFMs by feeding a polymer solution, containing a gas producing agent using single orifice spinneret is reported. Polysulfone‐dimethylacetamide solution containing NaBH4 is extruded through a stainless‐steel needle (single orifice spinneret) into HCl aqueous solution (coagulation bath) at specific rates. Effects of polysulfone concentration, temperature, and pH of coagulant bath on structure and performance of the HFMs are investigated. Synergy between hydrogen from NaBH4 hydrolysis and NIPS process benefits fabrication of HFMs with good hollow bore structure and high porous wall. The prepared HFMs show good dye separation.