製備超親水/超疏油薄膜於油水分離之應用

Design of Superhydrophilic/Superoleophobic Membranes for Oil/Water Separation

張家瑜(Chia-Yu Chang)

指導教授 ： 費安東 ； 張雍

中原大學/工學院/化學工程研究所/碩士(2017年)

https://doi.org/10.6840/cycu201700431

摘要

本研究以聚偏二氟乙烯(Polyvinylidene fluoride, PVDF)為基材，利用蒸氣誘導式相轉換法(Vapor-induced phase separation, VIPS)之程序製備薄膜；接著，利用疏水性苯乙烯(Styrene)與親水性極佳之磺基甜菜鹼甲基丙烯酸酯(Sulfobetaine methacrylate, SBMA)合成不同比例親疏水性之高分子(PS-r-PSBMA)，藉由反應誘導自沉積法(reaction-induced self-deposition process)，以邊合成邊塗佈的方式對PVDF薄膜進行改質。目的為製備超親水/超疏油薄膜於油水分離之應用。
將改質之PVDF薄膜以表面接觸角量測儀(Contact angle)測量其水/油接觸角以鑑定其親水/疏油程度、以掃描式電子顯微鏡(Scanning electron microscope, SEM)觀察其表面形態、X射線光電子能譜儀(X-ray photoelectron spectroscopy, XPS)與傅立葉轉換紅外線光譜儀(Fourier transform infrared spectroscopy, FT-IR)檢測其表面元素與鍵結，最後藉由油水分離實驗以及水份儀(Karl Fischer)量測含水率以檢測改質之PVDF薄膜過濾的分離效能。
反應時間、單體比例和固體含量等不同反應參數會使薄膜具有不同的親水程度，實驗結果顯示，當改質條件反應時間為5小時、styrene/SBMA單體比例為40/60和固體含量為5 wt%時具有最佳的親水與水中疏油性質，其水接觸角在數秒內降為0˚，水中油接觸角高達140˚。另外，以五種不同的油製備油水乳化物，分別為甲苯、己烷、十六烷、才油和大豆油，並在低壓下(0.5 atm)進行油水分離的測試。接著利用卡式水分儀測試含水率，分離效率高達99%，證明了此材料在廢水處理¬-油水分離方面是具有發展潛力的。

關鍵字

原位聚合 ； 自組裝 ； PVDF薄膜 ； PS-r-PSBMA共聚物 ； 油水分離

並列摘要

In this study, we prepared poly(vinylidene fluoride) (PVDF) membranes by vapor-induced phase separation (VIPS) process. Then, we modified the membranes using styrene and sulfobetaine methacrylate (SBMA) (PS-r-PSBMA) via reaction-induced self-deposition process, in which the polymerization and coating of styrene and SBMA on the membranes occur at the same time. The goal was to prepare superhydrophilic/superoleophobic membranes that can easily separate oil-in-water emulsions by gravity separation process.
The membranes were characterized by water and oil contact angle measurement, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FT-IR). Oil-in-water emulsion separation was performed by filtration under low transmembrane pressure (0.5 atm), Karl Fischer method enabled to evaluate the composition of the permeate and of the retentate, and thus the separation efficiency of the membrane.
Different reaction parameters such as the reaction time, the monomer ratio and the solid content were varied in order to optimize the surface hydrophilicity of the membranes. The results showed that the reaction carried out for 5 hours, using a styrene/SBMA ratio of 40/60 and a total solid content of 5 wt% led to desirable hydrophilic property as the water contact angle was found to be 0˚ within 10 seconds after contact between the water droplet and the membrane. And oil contact angle under water was 140 ˚. Then, toluene, hexane, hexadecane, diesel and soybean oil were used to prepare oil-in water emulsions and separated by membrane filtration under low transmembrane pressure (0.5 atm). In addition, a separation efficiency higher than 99% was measured in both cases. Thus these membranes hold promise as potential materials for breaking of O/W emulsions.

並列關鍵字

In-situ polymerization ； self-assembling ； PVDF membrane ； PS-r-PSBMA copolymer ； O/W separation

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