One-pot fabrication of SF-DA@PVDF membrane for dye adsorption and oil-in-water emulsion separation

Abstract

With industry development, the reuse of water and oil resources has become an urgent problem. At present, the evolution of simple-minded approaches to attain modification on the membrane surface for a more complex circumstance, such as oily wastewater and dyes at the same time, has become a red-hot but challenging topic for research. Membrane separation technology has successfully built up to cope with these issues, such as oil-in-water emulsion separation and dye adsorption owning to its benign mechanical characteristics and low power consumption. Therefore, we report a simple-minded one-step approach for uses in oil-in-water emulsion separation and dye adsorption. In this work, a new multifunctional membrane surface is constructed via the concurrent incorporation of silk fibroin (SF) and dopamine hydrochloride (DA) in co-deposition to reach a large flux for complex wastewater separation. The qualified membrane has super hydrophilic in the air and has brilliant oil adhesion resistance underwater. It works comfortably on oil-in-water emulsions (over 10400 L m−2 h−1 bar−1) or dyes (above 3738.68 mg m−2). More importantly, excellent adsorption efficiency (>99%) and extensive adsorption capability (over 2071.91 mg m−2) were achieved by the oil-in-dye emulsion that stabilized with surfactant. It not only possesses a broad span of use outlooks but also enlightens imports for the evolution of functional coating in the future.