上海科技大学知识管理系统

Membrane fouling during long-term usage severely restricts the practical application of membrane separation technology for oil-in-water emulsion treatment. Underwater superoleophobic/superhydrophilic membrane with superior self-cleaning and flux recovery performance is highly desirable, owing to its high anti-fouling ability in an oil-in-water emulsion. Herein, a polyglycidyl methacrylate-/iminodiacetic acid (IDA)/Fe(III) superhydrophilic layer was fabricated onto a polyvinylidene fluoride (PVDF) microfiltration membrane via radiation-induced graft polymerization, and subsequent adsorption of Fe(III) as the photo-Fenton activation site, labeled as Fe@PVDF, in which the loading capacity of Fe(III) was 18.31 wt%. The grafted layer acts as both, an underwater superoleophobic/superhydrophilic layer (OCA˃150o) for highly effective oil-in-water emulsion separation (99.4 %) and as a photo-Fenton activation layer for self-cleaning in 10 min under visible light irradiation with high flux (⁓2300 L m−2 h−1 bar−1). The mineralization of contaminants on the membrane surface was then systematically investigated using a series of experiments, X-ray absorption fine structure (XAFS) measurements, and density functional theory (DFT) calculations, demonstrating that the Fe/IDA site with an Fe(III) atom acts as the active site with an optimal energy gap for photo-Fenton self-cleaning activation and greatly accelerates the Fe (III) to Fe (II) cycle. Moreover, our work shows a pathway for photo-Fenton self-cleaning membranes combining excellent stability (15 cycles), and satisfactory oil-in-water emulsion separation with quick and reliable flux recovery performance, revealing their huge potential application in advanced sewage treatment. © Elsevier B.V.