透過蒸氣式誘導相轉化方法調整聚(偏二氟乙烯-六氟丙烯)薄膜的型態有效分離富含油相的乳化物

Adjusting the morphology of poly(vinylidene fluoride-co-hexafluoropropylene) membranes by the VIPS process for efficient oil-rich emulsion separation

張翔諭(Hsiang-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(2019年)

https://doi.org/10.6840/cycu201900506

摘要

在該研究中，PVDF-co-HFP共聚物與2-吡咯烷酮溶劑一起使用以形成平板膜。2-吡咯酮是PVDF-co-HFP的弱溶劑，其將產生高黏度的鑄膜液。高黏度溶液可在蒸氣誘導相分離的過程中提供快速的相分離，以產生雙連續結構。為了防止在膜形成之前聚合物溶液凝膠化，將恆濕恆溫箱溫度設定為60℃，PVDF-co-HFP濃度為12％，15％，17％，20％和25％。在製備的膜中，15％PVDF-co-HFP膜具有最佳的機械性能和形態。然後，在用於重力過濾和掃流過濾中，在使用或不使用界面活性劑的情況下，將薄膜應用於分離油包水的乳化物。在每種情況下，獲得了高通量和分離效率，並且膜在各個方面（通量，分離效率，機械可持續性）優於具有相似孔徑/孔隙率的商業疏水性聚（偏二氟乙烯）（PVDF）膜。在油包水分離中的性能而言，與具有相似孔徑的商業PVDF膜（66L/m2 h）相比，PVDF-co-HFP膜具有更高的通量（700L/m2 h）。PVDF-co-HFP膜可用於分離不同油的乳化物，分別為甲苯，己烷，十六烷，柴油和大豆油，分離效率為99.58％，99.7％，99.76％，99.78％和99.1％。

關鍵字

P（VDF-co-HFP）薄膜 ； 控制結構 ； VIPS製程 ； 油水分離 ； 富含油相的乳化物。

並列摘要

In this study, PVDF-co-HFP copolymer was used together with a 2-pyrroildone solvent to form a flat sheet membrane. 2-pyrroildone is a weak solvent for PVDF-co-HFP that will yield a high viscosity casting solution. The viscosity solution can provide a fast phase separation during vapor induced phase separation to create a bi-continuous structure. To prevent gelation of the polymer solution before membrane formation, the temperature was set to 60°C in chamber and the PVDF-co-HFP concentration was between to 12%, 15%, 17%, 20% and 25%. Among the prepared membranes, the 15% PVDF-co-HFP membrane has the best mechanical property and morphology. Then, the membrane is fully characterized before being applied to the separation of water-in-oil emulsions, from versatile oil-rich phases, with or without the use of surfactants, in both dead-end gravity driven process and cross-flow process.
In each situation, high flux and separation efficiencies were obtained, and the membrane outperformed commercial hydrophobic poly(vinylidene fluoride) (PVDF) membranes of similar pore size/porosity in every aspect (flux, separation efficiency, mechanical sustainability). In terms of its performance in water-in-oil separation, the PVDF-co-HFP membranes had a higher flux (700L / m2 h) compared to the commercial PVDF membrane (66L / m2 h) with similar pore size. PVDF-co -HFP membranes were used to separate emulsions of water with different types of oils such as toluene, hexane, hexadecane, diesel and soybean oil, obtaining separation efficiencies of 99.58%, 99.7%, 99.76%, 99.78% and 99.1%, respectively.

並列關鍵字

P(VDF-co-HFP) membrane ； structure control ； VIPS process ； W/O separation ； oil-rich emulsions.

參考文獻

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