Development of a composite membrane with underwater-oleophobic fibrous surface for robust anti-oil-fouling membrane distillation

Kunpeng Wang; Deyin Hou; Peng Qi; Kuiling Li; Ziyi Yuan; Jun Wang

doi:10.1016/j.jcis.2018.11.040

Development of a composite membrane with underwater-oleophobic fibrous surface for robust anti-oil-fouling membrane distillation

J Colloid Interface Sci. 2019 Mar 1:537:375-383. doi: 10.1016/j.jcis.2018.11.040. Epub 2018 Nov 13.

Authors

Kunpeng Wang¹, Deyin Hou², Peng Qi³, Kuiling Li¹, Ziyi Yuan⁴, Jun Wang¹

Affiliations

¹ Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China.
² Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China. Electronic address: dyhou@rcees.ac.cn.
³ School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China.
⁴ School of Resources Environmental and Chemical Engineering, Nanchang University, Nanchang 330031, China.

PMID: 30465974
DOI: 10.1016/j.jcis.2018.11.040

Abstract

Membrane fouling caused by non-polar foulants is a challenging problem for hydrophobic membranes, which hinders the industrial implementation of membrane distillation (MD). The hydrophilic coating can create a hydration layer at solid-water interface, thereby the hydrophilic surfaces are expected to supply a barrier inhibiting adhesion of hydrophobic foulants. Hence, it should be possible to develop anti-fouling composite membranes through constructing a hydrophilic skin layer onto hydrophobic MD membranes. Herein, we fabricated a novel composite membrane for excellent anti-oil-fouling performance in MD process by electrospinning polyetherimide (PEI) nanofibers on the hydrophobic polyvinylidene fluoride (PVDF) membrane surface, followed by cross-linking with ethanediamine (EDA). The membrane morphology and structure properties, surface zeta potential and wettability, thermal stability were all systematically characterized, and force spectroscopy was used to quasi-quantitatively evaluate oil-membrane adhesion force. Compared with the PVDF membrane, the PVDF/PEI-EDA composite membrane exhibited strong resistance to crude oil with underwater oil contact angle of about 145° and low oil-membrane adhesion force, which contributed to the stable performance during MD desalinating an oily and saline solution. The fabricated composite membrane with underwater-oleophobic fibrous surface can effectively mitigate oil-fouling in MD and promote MD to treat highly saline wastewater with high concentration of hydrophobic foulants.

Keywords: Composite membrane; Electrospinning; Membrane distillation; Membrane fouling; Oleophobic surface.