二氧化矽/醋酸纖維素中空纖維膜製備及應用於油水分離效能之研究

Preparation and application of silicon dioxide/cellulose acetate hollow fiber membrane on the oil/water separation

楊承叡(Cheng-Jui Yang)

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(2019年)

https://doi.org/10.6840/cycu201900559

摘要

本研究製備二氧化矽(Silicon dioxide, SiO2)/醋酸纖維素(Cellulose acetate, CA) 混摻中空纖維膜，並應用在含柴油乳化液之分離。研究中，利用醋酸纖維素溶解在NMP (N-Methyl-2-pyrrolidone)溶劑中配置成紡絲液，以濕式紡絲法製備CA中空纖維薄膜，探討芯液組成對CA中空纖維薄膜結構型態與油水乳化液分離效能的影響。接著將SiO2摻入CA紡絲液中，製備SiO2/ CA混摻中空纖維薄膜，並應用於油水乳化液分離。最後，利用改質的聚多巴胺(polydopamine, PDA)塗佈SiO2（mSiO2）奈米粒子，製備mSiO2 / CA混摻中空纖維薄膜，並比較其對油水乳化液之過濾通量與抗垢能力。
首先探討紡絲時，不同芯液組成對CA中空纖維薄膜的結構型態與柴油/水乳化液分離效能影響，實驗結果發現，芯液中PEG 200 /水的比例高於75%時，可以完全消除CA中空纖維膜的內皮層，使薄膜的純水通量從340±15 LMH提升至454±24 LMH，且對柴油乳化液的阻擋率高於99%。接著在CA紡絲液中加入SiO2奈米粒子，探討不同含量的SiO2奈米粒子對於SiO2/ CA中空纖維薄膜的油水分離效能與抗垢能力的影響。利用FESEM、XPS和EDX鑑定證實，SiO2奈米粒子確實混摻入CA中空纖維薄膜。油水分離測試實驗結果顯示，加入0.1 wt%的SiO2奈米粒子所製備之CA中空纖維膜，具有最高的純水通量(534 LMH)與良好的通量回復率(77.28%)，以及較高的抗垢性能。
最後將經PDA改質之SiO2奈米粒子（mSiO2）加入CA紡絲液中，製備改質的mSiO2 / CA中空纖維混摻薄膜。利用XPS和EDX對薄膜進行分析，發現PDA塗覆的SiO2奈米顆粒均勻地分散在膜中。此外，在薄膜抗垢測試中發現，mSiO2 / CA混摻中空纖維薄膜，具有最高的通量回復率(85.75%)與最低的總結垢比(32.64%)，顯示了mSiO2 / CA混摻中空纖維薄膜具備優秀的抗垢能力。

關鍵字

醋酸纖維素 ； 中空纖維薄膜 ； 二氧化矽 ； 聚多巴胺 ； 油水分離

並列摘要

In this study, silicon dioxide (SiO2)/cellulose acetate (CA) blended hollow fiber membrane was prepared for oil/water emulsion separation. First, CA was dissolved in NMP (N-Methyl-2-pyrrolidone) to form the CA/NMP dope solution. The CA hollow fiber membrane then was prepared by a wet spinning process to investigate the effect of bore liquid composition on the morphology and diesel/water emulsion separation performance. Secondary, SiO2 was mixed into the CA spinning dope to prepare a SiO2/CA blended hollow fiber membrane, which was also applied to the separation of diesel/water emulsion. Finally, modified SiO2 (mSiO2) was preparet by coating polydopamine (PDA) onto SiO2 nanoparticle to prepare mSiO2/CA blended hollow fiber membrane to study the filtration flux and anti-fouling ability of the oil-water emulsion.
The experimental results show that when the ratio of PEG 200 / water in the bore liquid was higher than 75%, the lumen skin layer of the CA hollow fiber membrane was completely eliminated, and the pure water flux of the membrane was increased from 340±15 LMH to 454±24 LMH, and the rejection of diesel was higher than 99%. It was confirmed by FESEM, XPS and EDX identification that the SiO2 nanoparticle was actually mixed into the CA hollow fiber membrane. The oil-water separation test results showed that the CA hollow fiber membrane prepared by adding 0.1wt% SiO2 nanoparticle had the highest pure water flux (534 LMH) and good flux recovery rate (77.28%) and higher anti-fouling performance. The mSiO2/CA hollow fiber blended membrane was analyzed by XPS and EDX, and it was found that the PDA-coated SiO2 nanoparticle was uniformly dispersed in the membrane. In addition, it was found in the anti-fouling test that the mSiO2 /CA blended hollow fiber membrane had the highest flux recovery rate (85.75%) and the lowest decay ratio (32.64%), indicating that the mSiO2 /CA blended hollow fiber membrane had excellent anti-fouling ability.

並列關鍵字

cellulose acetate ； hollow fiber membrane ； silica dioxide ； polydopamine ； oil water separation

參考文獻

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