Deep eutectic solvent engineered MXene ultrafiltration membrane for enhanced treatment of oily wastewater

Surface modified MXene based membranes are emerging as promising technology for the effective treatment of oily wastewater. Despite their potential, achieving enhanced membrane permeability and antifouling performance while preventing MXene oxidation and aggregation remains challenging. In this study, a novel ultrafiltration membrane incorporating Deep Eutectic Solvent (DES) modified MXene nanocomposite was fabricated using the phase inversion technique for efficient separation of oil-water emulsions. Among various characterizations, X-Ray Diffraction (XRD) analysis indicated an increase in interlayer spacing after DES treatment, suggesting structural changes in MXene nanosheets whereas Fourier-Transform Infrared Spectroscopy (FTIR) analysis revealed improved functional groups associated with the surface modification. The synthesized reline based DES-MXene nanocomposite was incorporated into a Polysulfone (PSF) membrane matrix to improve the pore structure and performance of the ultrafiltration membrane at Transmembrane Pressure (TMP) of 1 bar. Compared to pristine PSF and MXene/PSF membranes, the developed DES-MXene/PSF membrane at 0.1 wt% nanocomposite concentration exhibited improved Pure Water Permeability (PWP) of 213.71 LMH/bar along with separation efficiency >99.07% for n-hexane, diesel and corn oil emulsions concentrations of 1:100 v/v. Essentially, DES intercalation within MXene layers improves the wettability that assists in water molecule transport by inhibiting oil droplet attachment on the surface of the membrane. Moreover, the antifouling property of the membranes was analyzed against Bovine Serum Albumin (BSA) and Humic Acid (HA) foulants. The comparative fouling filtration result showed that DES-MXene/PSF membrane exhibited a higher Flux Recovery Ratio (FRR) and less irreversible fouling. The FRR against BSA and HA for the optimized membrane was obtained to be 68.7% and 88.1%, respectively. Hence, the combination of anti-fouling and high permeability indicates that DES-MXene/PSF membrane can provide promising performance for efficient wastewater treatment.