Composite membrane with electrospun multiscale-textured surface for robust oil-fouling resistance in membrane distillation

• DOI: 10.1016/j.memsci.2017.10.017
• Publication Date: 2017-10-14T15:45:30Z
• Authors: Deyin Hou; Zhangxin Wang; Kunpeng Wang; Jun Wang; Shihong Lin
• Keywords: Membrane fouling; 660; Oil adhesion; Membrane distillation; 02 engineering and technology; Underwater oleophobicity; 0210 nano-technology; Hydrophilicity

Abstract In this study, we developed composite membranes with a hydrophobic substrate and a hydrophilic top surface using electrospinning to mitigate oil fouling in membrane distillation (MD). The electrospinning approach can be universally applied to any hydrophobic membrane substrate and to ensure the non-wetting condition of the substrate due to the electrospun fibrous structure. Using this approach, polytetrafluoroethylene (PTFE) hydrophobic substrate was coated with two different hydrophilic fibrous networks, including a cellulose acetate (CA) fibrous network and a nanocomposite fibrous network comprising CA and silica nanoparticles (SiNPs). We characterized the pristine and the modified membranes using contact angle measurements and tensiometer-based oil probe force spectroscopy, and tested the anti-fouling performance of the different membranes in MD experiments using a saline crude-oil emulsion as the feed solution. While both coatings offered significant improvement in oil fouling resistance compared to the substrate PTFE membrane, the nanocomposite CA-SiNPs fibrous coating outperformed the CA coating in terms of hydrophilicity, oil adhesion resistance, and anti-oil-fouling performance in MD experiments.