Eco‐Friendly Hollow Fiber Nanofiltration Membranes for Efficient Water Desalination

ABSTRACT Water scarcity is a critical global issue requiring sustainable and efficient desalination. This study introduces a novel eco‐friendly hollow fiber nanofiltration membrane for water desalination, employing a wet spinning method to create membranes from polyether sulfone (PES), polyethylene glycol (PEG), and polyvinylpyrrolidone (PVP). The prepared membrane demonstrated significant improvements in pure water permeability (PWP) and salt rejection rates, achieving up to 94% rejection. Scanning Electron Microscopy (SEM) analysis revealed a unique asymmetric structure characterized by small macro‐voids towards the outer edge of the membrane. Increasing the dope extrusion rate (DER) from 2.0 to 2.5 cm 3 /min notably enhanced molecular orientation, optimizing rejection rates. Additionally, increasing the pH elevation from 5.5 to 6.5 further improved rejection due to altered membrane surface charges. Long‐term and thermal stability assessments confirmed robust membrane performance over a temperature range of 10°C–70°C, indicating its viability for diverse applications. This research significantly contributes to overcoming existing knowledge gaps, particularly regarding the effects of the dope extrusion rate (DER), and advances practical, sustainable desalination technology.