High-performance filtration PAN-based electrospun nanofibers membranes with hierarchical structure for oil separation

Abstract

Nanofibers-based membranes are essential separation membranes due to their several advantages for oil-water separation. However, the low mechanical strength is the weak point of nano-fibers membranes due to their small fiber diameters, extremely porous structure, and insufficient fiber bonding. This study fabricated a multilayers configuration of polyacrylonitrile (PAN) electrospun nanofibers membrane of a hierarchical structure by electrospinning three solutions of different PAN concentrations (10, 13, and 16 wt.%) consequently. Then, the solvent-vapor method was used as a post-treatment modification approach to improve the mechanical properties of the fabricated PAN-based multilayers nanofibers membrane via solvent-induced fusion of interfiber junction points. The surface morphology, fibers size, porosity, and mechanical properties were investigated to evaluate the modification effect on the fabricated membranes. According to the analysis results, the post-treated multilayers PAN-based nanofibers membranes significantly enhanced their strength and flexibility. In addition, the fabricated membranes were applied in emulsified oil filtration using a cross-flow cell filtration system. The post-treated multilayers PAN-based membrane by vapor-solvent showed a high performance with a long operating time.