Facile fabrication of organic superhydrophobic corn silk-derived cellulose acetate nanofiber for the effective sequestration of oil from oil–water mixture

• Published in: Water science and technology Vol. 88; no. 6; pp. 1608 - 1620
• Main Authors: R, Sivashankar, K, Anand Kishore
• Format: Journal Article
• Language: English
• Published: London IWA Publishing 15.09.2023
• Subjects: Acetates; Acetic acid; Acids; Analytical methods; Calorimetry; Cellulose; Cellulose acetate; Cleaning; Contact angle; Corn; corn silk cellulose acetate; Differential scanning calorimetry; Emulsions; Fabrication; Fourier transforms; Gravity; Hydrophobic surfaces; Hydrophobicity; Infrared analysis; Infrared spectroscopy; Membranes; Mineral oils; Mixtures; Morphology; nanofiber; Nanofibers; Oil spills; oil–water sequestration; Petroleum; Polyacrylonitrile; Polymers; Scanning electron microscopy; Separation; Silk; Solvents; Sorbents; Spectrum analysis; superhydrophobic membrane; Temperature; Thermogravimetric analysis; Toluene; Viscosity; Water; X-ray diffraction
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2023.293

Abstract Oil spills and subsequent cleanup by oil–water separation remain a global concern. For the first time, corn silk-derived cellulose acetate (CSCA) and polyacrylonitrile (PAN) composite nanofiber are reported to create a superhydrophobic oil–water sequestration membrane. CA : PAN solutions with various PAN concentrations were evaluated for viscosity and conductivity. A CSCA nanofiber membrane was fabricated through electrospinning, which was superhydrophobic and oleophilic in water. Scanning electron microscope, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis/differential scanning calorimetry were used to analyze the membrane's morphological features. CSCA nanofibers formed a highly spherical bead with a maximum contact angle of 156° (>120°) in pure water solutions, demonstrating their superhydrophobicity. This study found that membranes can remove oil from oil–water mixtures and emulsions, as gravity is the only force required for propelling the system. Mineral oil had the highest oil sorption capability (908%), while toluene had the lowest (664%). For mineral oil–water mixtures, the CSCA membrane has the greatest separation flux at a maximum of 442 L/m2/h and the best separation efficiency at up to 99.67%. These findings provide strong support for using an as-prepared CSCA nanofiber membrane as a viable reusable oil sorbent in oil spill cleaning.