Multifunctional electrospun PAN/activated carbon nanofiber membranes for high-efficiency air filtration and oil–water separation

Abstract The growing environmental pollution from airborne particulates and oily wastewater has created an urgent need for advanced multifunctional filtration materials. The study evaluates electrospun polyacrylonitrile/activated carbon (PAN/AC) nanofiber membranes developed as dual-purpose filters for air-purification and oil–water separation. PAN solutions containing 5 %, 10 %, and 15 % AC were electrospun under optimized conditions. Among them, the PAN/10 % AC membrane exhibited the most uniform nanofiber morphology with an average diameter of 495–500 nm and the highest porosity (86.99 %) determined by mercury intrusion porosimetry (MIP), while maintaining structural stability. The addition of AC to PAN solutions resulted in better thermal stability according to thermogravimetric analysis (TGA) while tensile tests showed PAN/10 % AC achieved maximum mechanical strength at 2.907 MPa with 33.45 % elongation because of effective AC distribution and polymer-filler bond formation. The PAN/10 % AC membrane showed exceptional PM2.5 filtration performance with 99.29 % removal efficiency and 589.3 Pa pressure drop while achieving a QF of 0.0084 Pa -1 . Additionally, the membrane exhibited strong hydrophobic proporties, resisting water penetration for over 10 min, while showing rapid diesel oil permeation due to its oleophilic nature. Overall, the PAN/10 % AC membrane exhibits an optimal balance of structural, mechanical, and functional properties for environmental remediation applications, particularly high-performance air filtration and oil–water separation.