Preparation of an Asymmetric Membrane from Sugarcane Bagasse Using DMSO as Green Solvent

• Published in: Applied sciences 2019-08, Vol.9 (16), p.3347
• Main Authors: Thi To Nu, Dang, Phi Hung, Nguyen, Van Hoang, Cao, Van der Bruggen, Bart
• Format: Article
• Language: English
• Subjects: Acetic acid; Acetic anhydride; Antifouling substances; asymmetric membrane; Asymmetry; Atomic force microscopy; Bagasse; Biodegradable materials; Bleaching; Calorimetry; Catalysts; Caustic soda; Cellulose acetate; Cellulose acetate membranes; Contact angle; Differential scanning calorimetry; Dimethyl sulfoxide; DMSO; Ethylenediaminetetraacetic acids; Evaluation; Fourier analysis; Fourier transforms; Functional groups; Hydrogen peroxide; Infrared analysis; Infrared spectroscopy; Lignin; Magnetic resonance spectroscopy; Membranes; Moisture content; Molecular weight; NMR; NMR spectroscopy; Nuclear magnetic resonance; phase inversion; Polymers; Pretreatment; Scanning electron microscopy; Sodium hydroxide; Solvents; Substitution reactions; Sugarcane; sugarcane bagasse; Sulfuric acid; Thermal analysis; Thermogravimetric analysis; Titration; Viscosity; Water content; X-ray diffraction
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app9163347

Asymmetric cellulose acetate membranes have been successfully fabricated by phase inversion, using sugarcane bagasse (SB) as the starting material. SB is a raw material with high potential to produce cellulose derivatives due to its structure and morphology. Cellulose was extracted from SB by pretreatment with solutions of 5 wt% NaOH, 0.5 wt% EDTA; then bleached with 2 wt% H2O2. Cellulose acetate (CA) was prepared by the reaction between extracted cellulose with acetic anhydride, and H2SO4 as a catalyst. The obtained CA exhibited a high degree of substitution (2.81), determined with 1H-NMR spectroscopy and titration. The functional groups and thermal analysis of the extracted cellulose and the synthesized CA have been investigated by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The change in the crystallinity of the extracted cellulose and CA was evaluated by X-ray diffraction (XRD) spectroscopy. Asymmetric membranes were fabricated using dimethyl sulfoxide (DMSO) as the solvent, with a casting thickness of 250 µm. The obtained membranes were studied by scanning electron microscopy (SEM), DSC and atomic force microscopy (AFM). The hydrophilicity of the membranes was evaluated, as demonstrated by the measurement of water contact angle (WCA) and water content. Furthermore, the antifouling properties of membranes were also investigated.