Electrospun polysulfone hybrid nanocomposite fibers as membrane for separating oil/water emulsion

Abstract

Commercial polymer membranes are largely utilized to separate oil/water mixtures, however membrane fouling, flux decline and short lifetime often inhibit their high performance. In order to resolve these drawbacks of the commercial membranes, we introduce a surface modification strategy following the electrospinning method. Electrospun fibers of polysulfone (PSf)/iron oxide (FeO)/halloysite nanotubes (HNT) nanocomposite is applied to modify the polyether sulfone (PES) standard membrane support surface for developing highly efficient oil/water emulsion separating membranes. This facile and simple spinning process for shorter periods ensures nanocomposite coatings on the standard PES membranes and allows better oil/water separation process. We analyze the structural and morphological characteristics of the modified membrane surface in addition to the hydrophilicity from contact angle studies. FeO nanoparticles of 2-5 nm and HNTs of <50 nm size mixed in PSf produce fibers of 531 ± 162 nm average diameter at a relatively lower applied electrical voltage 14.5 kV, compared to PSf. Under water and under oil contact angle values are used to prove the surface characteristics of the membranes and TOC values for the emulsion separation performance. From PES support to PSf and to PSf/HNT-FeO, the TOC values respectively change from 67 % to 75 % and to 79 %. We find the moderately hydrophilic membranes resulting in the higher permeate flux and quicker separation performance. We believe this study provides a notable solution to modify the surface of commercial membranes for better emulsion separation performance.