Pre-oxidized PAN/PVP nanofibrous membranes with enhanced mechanical robustness and chemical stability for high-flux separation of oily wastewater from petroleum productionOA

Discharge of oily wastewater,generated from oil and gas production can lead to severe marine and soil contamination,posing long-term threats to ecosystems and water security.Therefore,developing environmentally sustainable,high-flux,and chemically robust separation membranes is crucial for green petroleum production and water reuse.In this work,pre-oxidized polyacrylonitrile/polyvinylpyrrolidone(p-PAN/PVP)nanofibrous membrane has been fabricated to address this challenge aforementioned.The PVP,during pre-oxidation,formed cross-linked junctions,reinforcing the mechanical stability and the resistance to harsh chemical conditions.Additionally,our membrane also exhibited superhydrophilicity in air,underwater super-oleophobicity,low oil adhesion,ultrahigh flux(>8500 L·m^(-2)·h^(-1)·bar^(-1)),and>99.8%separation efficiency for both crude-oil-in-water and surfactantstabilized emulsions.More importantly,the p-PAN/PVP membrane could maintain integrity and wettability under acidic,alkaline,and high-salinity environments(1 M HCl,1 M NaOH,10 wt%NaCl)as well as in organic solvents(N,N-dimethylformamide,N,N-dimethylacetamide,dimethyl sulfoxide,etc).Our study provides a sustainable strategy to protect vulnerable ecosystems and promote cleaner energy development.