鑒於傳統油-水分離方法的缺點，利用表面特殊潤濕性的創造，可望開發出新穎的油-水分離方法。透過表面特殊潤濕性油-水分離機制的深入探討，更預期可以設計出高效率、降低能源消耗和快速簡單的分離程序。本研究以聚酯纖維紡織品做為基材，水性鐵氟龍分散液 (PTFE DISP)為浸鍍液，透過不同濃度及不同的塗佈次數，將其修飾成疏水/親油的分離膜。並用以處理不含界面活性劑 (surfactant-free) 的水在油中 (W/O) 及油在水中 (O/W) 乳化液。利用水滴的靜態接觸角及滑落角鑑定分離膜的疏水潤濕型態(Meta或Wenzel)，並測定分離膜的分離成效，探討其分離機制。
研究結果顯示，聚酯纖維紡織品經由PTFE DISP (30, 40, 60 wt%) 分別塗佈2和3次，可以成功分離水在甲苯中 (W/O) 乳化液。在分離機制的探討中顯示，表面的孔徑大小是決定分離與否成功的主要因素，若表面孔徑太大，會使得乳化液直接通過分離膜並依然呈現乳白色；若孔徑足夠小，水滴得以被分離，過濾液會變成澄清無色。而且在分離過程中，因為甲苯會潤濕分離膜，因此，分離前類似蓮葉或玫瑰花瓣的表面在分離過程中會轉變成類似豬籠草口緣的滑溜表面。由於疏水機制事實上已經轉變，原本乾的分離膜的潤濕型態並不會影響到分離效能。此外，若處理大量乳化液時，會因為被分離出來的小水滴累積成水層，進而阻隔乳化液與分離膜的接觸。此時，可以將分離裝置傾斜，使水滴滑落，露出乾淨的分離膜表面，使得分離得以持續進行。
另外，聚酯纖維紡織品經由PTFE DISP (30, 40, 60 wt%) 塗佈1~3次的分離膜皆可以成功分離甲苯在水中 (O/W) 的乳化液。但是，成功分離的主要因素是油滴接觸到疏水/親油分離膜的機率，並非受到分離膜本身的潤濕型態或孔徑大小的影響。本研究透過在乳化液上方加裝攪拌葉，增加油滴接觸分離膜的機率，促使原本無法分離的O/W乳化液得以成功分離。結果也顯示轉速越高，分離時間就越短。另外，分離大量O/W乳化液時，分離膜先是被甲苯潤濕而達到飽和，繼而過多的甲苯會通過分離膜被分離。

In view of disadvantages of traditional methods for oil-water separation, it’s expected to develop novel method by creating special wettability surface. Through the discussion of oil-water separation mechanisms of special wettability surface, it can be expected to deign a separation procedure with high efficiency, low energy consumption and simple method. In our research, we create the hydrophobic/oleophilic membrane by coating PTFE dispersion with different concentration and coating times. The separation membranes are used to separate surfactant-free W/O(water-in-oil) and O/W(oil-in-water) emulsions.
From the experimental results, separation membranes coated by PTFE DISP(30, 40, 60 wt%) with twice and three coating times are successful to separate water-in-toluene emulsions. And discussion on separation mechanism, pore size is the main factor to dominate the separation whether is successful or failed. Furthermore, there exists water repellency transition during separation process. Since toluene wets the separation membrane, the surface would become slippery surface Owing to this transition, the wetting modes of dry surfaces don’t influence the separation. In addition, in case of separating large amounts of emulsions, water would become an layer to resist the emulsion to be separated. Therefore, the separation device could be tilted and then remove water from device.
Separation membranes coated by PTFE DISP(30, 40 , 60 wt%) with 1~3 coating times can separate toluene-in-water emulsion. However, contact probability of oil droplets with separation membrane is the main factor to dominate the separation. We add a stirring blade above the emulsion to increase the contact probability in this study. When we increase the rotation speed, the separation time would reduce.

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