Study On Surface Modification Of Glass Fiber Membrane And Separation Of Oil And Water

Membrane separation technology has been widely used in oil-water separation owing to its high separation accuracy, environment friendly and small footprint. However, the existing polymer membrane materials cannot meet the actual needs of oily water wastewater owing to the poor performances including narrow operating temperature, poor chemical erosion resistance, and other shortcomings. It has very important significance to select and develop the membrane material that has good heat resistance, good solvent resistance to prepared excellent performance separation membrane. Further, the glass fiber membrane was widely used in a variety of fields due to high temperature resistance, chemical resistance, good transparency, soft, easily processed into membrane modules and other high-quality physical and chemical properties. Therefore, this study choose glass fiber membrane as the base membrane to hydrophilic modified in order to obtain the membrane with chemical corrosion resistance, heat resistance, high flux and good separation performance of oily wastewater.In this study, we grafted epoxy groups on the membrane surface based on to the SN2 reaction of the chloride group of epichlorohydrin (EPI) with the silicon hydroxyl on glass fiber membrane surface occurs nucleophilic reaction in alkaline conditions.Then polyethyleneimine (PEI) grafted on membrane surface owing to the reaction of epoxy groups with amino group to preparation super-hydrophilic membrane for oil-water separation. In this paper, three modified membranes:GF-g-PEI60000, GF-g-PEI 10000 and GF-g-PEI600 were prepared successfully. Total reflection infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the membrane surface chemical composition. The membrane surface morphology was observed by the field emission scanning electron microscopy (FESEM). The change of membrane water flux, oil-water separation capacity and membrane antifouling performance were evaluated by gravity drive dead-end filtration. The solvent resistance of the modified membrane were characterized by solvent immersion test. The membranes were boiled in 100℃ water for 15 days, then detect the change of separation performance and surface morphology of the membranes, to characterize the thermal stability performance of the membrane.The results show super-hydrophilic glass fiber modified membrane have been prepared by grafting the PEI60000, PEI10000 and PEI600 on the glass fiber membrane surface. The modified membranes have good separation for dispersed oil and the rejection for various emulsified oils can reached more than 99%. Meanwhile, the modified film also showed good chemical stability, thermal stability performance.