聚醯胺/三醋酸纖維素複合薄膜之製備及其奈米過濾之應用

Preparation of Polyamide/Cellulose Triacetate Composite Membrane for Nanofiltration

羅正嚴(Zheng-Yan Luo)

指導教授 ： 李魁然 ； 蔡惠安

中原大學/工學院/化學工程研究所/碩士(2018年)

https://doi.org/10.6840/cycu201800074

摘要

本研究利用非對稱三醋酸纖維素薄膜作為基材，以相較於其他胺單體較具抗氯潛力的Piperazine (PIP)與油相單體Trimesoyl chloride (TMC)經界面聚合反應，於三醋酸纖維素基材膜上形成聚醯胺層，製備成聚醯胺/三醋酸纖維素複合膜，並應用於奈米過濾分離程序。
研究中探討製膜條件中PIP水相單體以及TMC有機相單體濃度對薄膜特性以及奈米過濾分離效能的影響。並利用最佳製膜條件所製備之薄膜探討奈米過濾操作條件，如鹽類與染料種類、進料濃度、進料溫度及操作壓力等對奈米過濾分離效能之影響。研究中同時測定其截留分子量以及抗氯效能。
在薄膜鑑定方面，利用場發射掃描式電子顯微鏡 (FESEM)觀察薄膜表面與截面之結構型態、利用原子力顯微鏡(AFM)觀察薄膜表面粗糙度、利用全反射傅立葉紅外線光譜 (ATR-FTIR)分析薄膜表面化學結構、以水接觸角測試薄膜親疏水性，並利用電位分析儀測試薄膜表面界達電位。
研究結果顯示，當PIP濃度為0.05 wt.%、TMC濃度為0.3 wt.%時，所形成之聚醯胺/三醋酸纖維素複合薄膜具有最佳奈米過濾分離效能，其純水透過通量為179 Lm-2h-1，硫酸鈉阻鹽率為98 %。對無機鹽類阻鹽率之順序為硫酸鈉>硫酸鎂>氯化鈉>氯化鎂。本薄膜為一帶負電荷之奈米過濾薄膜，其負電染料之截留分子量為600 g/mol、中性溶質Polyethylene glycol (PEG)截留分子量為1600 g/mol。此該薄膜經15,000 ppm次氯酸鈉處理一小時後，對Brilliant Blue R 染料的截留仍能維持99 %以上。

關鍵字

奈米過濾 ； 聚醯胺 ； 三醋酸纖維素 ； 薄膜 ； 染料 ； 鹽類

並列摘要

In this study, Polyamide(PA)/cellulose triacetate (CTA) composite nanofiltration membrane were fabricated through interfacial polymerization (IP) by using piperazine (PIP) and trimesoyl chloride (TMC) as monomer to form PA layer on to cellulose triacetate substrate.
The effect of IP conditions, such as PIP concentration and TMC concentrations on the properties and performances of prepared membranes were investigated. Moreover, the effects of nanofiltration operation conditions, such as salt and dye type, feed concentration, feed temperature and operating pressure, on the nanofiltration performances were also discussed. In addition, the molecular weight cut-off (MWCO) and chorine resistance of prepared membranes were also tested. The resultant PA/CTA composite membranes were characterized by using attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR), field-emission scanning electron microscope (FESEM), atomic force microscope (AFM), water contact angle and Zeta potential analyzer.
The results showed that the PA/CTA composite membrane had the best nanofiltration performances when the PIP concentration and TMC concentration was 0.05 wt.% and 0.3 wt.%, respectively. A nanofiltration performances with 179 Lm-2h-1 pure water permeation flux at 6 kg/cm2 and 98% sodium sulfate rejection were obtained through the resultant PA/CTA composite membrane. The salt rejection followed the order of Na2SO4 > MgSO4 > NaCl > MgCl2.
The prepared PA/CTA composite membrane in this study is a negatively charged nanofiltration membrane with a molecular weight cut-off of 600 g/mol for negative charge dye and a molecular weight cut-off of 1,600 g/mol for neutral solute polyethylene glycol (PEG). After treatment with 15,000 ppm sodium hypochlorite for 1 hour, the rejection of Brilliant Blue R dye by the prepared membrane is still above 99 %.

並列關鍵字

nanofiltration ； polyamide ； cellulose triacetate ； membrane ； dye ； salt

參考文獻

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