This study aims to demonstrate, for the first time, the potential of organic solvent nanofiltration (OSN) for ethanol recovery from a soybean oil/ethanol mixture. At the same time, it focuses on the practicality of the process by addressing simple membrane fabrication and enhancing the trade-off between permeability and selectivity. To this end, organic-resistant membranes were de-veloped using polyvinylidene fluoride (PVDF) as the base polymer, incorporating highly hydrophilic graphene hydroxyl (GOH) nanoparticles. The membranes were fabricated via non-solvent induced phase separation (NIPS), and the impact of GOH incor-poration at five different concentrations (0.25, 0.5, 0.75, 1, and 1.25 wt%) on their structural characteristics and functional performance was systematically investigated. Comprehensive characterization was carried out using field emission scanning electron microscopy (FESEM), attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), and energy-dispersive X-ray spectroscopy (EDX). Additionally, membrane properties were evaluated through contact angle measurements, swelling tests, and tensile strength analysis. The results revealed that increasing the GOH content up to 0.75 wt% led to the formation of more pronounced and elongated finger-like voids, improving membrane morphology. Furthermore, the addition of GOH significantly reduced the water contact angle, indicating enhanced hydrophilicity. Performance testing in the OSN process showed that membranes containing up to 0.75 wt% GOH exhibited an improved trade-off, achieving a maximum flux of 1.77 L/m2 h bar while maintaining an oil rejection of approximately 99%.

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