Tailored nanofibrous polyimide-based membranes for highly effective oil spill cleanup in marine ecosystems

Oil spills pose significant environmental threats to marine ecosystems and indirectly affect human health. They are often caused by tanker accidents and pipeline leaks. The persistence of hydrocarbons in the marine environment and their long-term ecological impacts necessitate efficient remediation strategies. Nanofibrous membranes made from polyimides with varying hydrophobicity present a promising solution for oil spill cleanup and oil/water separation. In this study, electrospun nanofibrous membranes were fabricated using 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) combined with 3,5-diamino-2,4,6-trimethylbenzenesulfonic acid (TrMSA) and 2,3,5,6- tetramethyl-p-phenylenediamine (TMPD) to produce bead-free nanofibers at optimized concentrations. These membranes exhibited hydrophobic characteristics and high oil absorption capabilities. The 6FDA-TMPD membrane achieved a maximum adsorption capacity of 76.50 ± 7.32 g g⁻¹ for Varinca crude oil, while the 6FDA-TrMSA membrane reached 80.05 ± 6.60 g g⁻¹. In comparison, the commercial 3M™ oil sorbent had a significantly lower capacity of 29.4 ± 3.8 g g⁻¹ for the same oil. The nanofibrous membranes also demonstrated superior performance in adsorbing gasoline and diesel and maintained their effectiveness across multiple cycles, highlighting their potential to mitigate the environmental impact of oil spills.