Fabrication of Forward Osmosis Membrane using Nata-de-Coco as Raw Materials for Desalination

以椰果為原料製作可進行海水淡化的正滲透膜

10.6937/TWC.202003/PP_68(1).0004

Liza Bautista-Patacsil；Mayzonee V. Ligaray；John Paulo C. Sayao；Joule Renniel F. Belosillo；Ramon Christian P. Eusebio；Aileen H. Orbecido；Arnel B. Beltran

Desalination ； Forward Osmosis ； Nata de coco ； 海水淡化 ； 正滲透膜 ； 椰果

台灣水利

68卷1期（2020 / 03 / 01）

36 - 43

英文

A Forward Osmosis (FO) membrane was fabricated using a locally available material nata de coco (NDC) to form a bacterial cellulose (BC) film. Sodium alginate was used to form composites with the BC film. Two concentrations (10% and 15%) of cross-linking agent, CaCl_2, were compared in terms of its performance as a FO membrane for application in desalination. Two salts were compared as draw solution: 2M sucrose (C_(12)H_(22)O_(11)) and 2M magnesium chloride (MgCl_2). The performance of the fabricated NDC-FO membrane was investigated in terms of water flux, salt flux and percent salt rejection in a laboratory-scale FO system. The 15% CaCl_2 solution was observed to give high water flux, low salt flux, and high salt rejection compared to the 10% CaCl_2. The 15% CaCl_2 solution produced a more tensile membrane compared to 10% CaCl_2, one endures pressure at the suction points of the FO module while the other breaks after some time of operation, respectively. The NDC-FO membrane has an average contact angle of 14.13° with an average thickness of 0.159 mm. The 2M MgCl_2 performs better than sucrose as a draw solution. The commercial Cellulose Tri-Acetate (CTA) FO membrane was used to benchmark the performance of NDC-FO membrane. The NDC-FO membrane produces a water flux of 4.01 LMH with 88.39% salt rejection, which is comparable to the water flux of CTA with 7.97 LMH and 100% salt rejection. Results showed the potential of nata de coco as raw material for FO membrane.

本研究通過使用當地特產的椰果（NDC）作為材料製作正滲透（FO）膜，從而形成細菌纖維素（BC）膜。同時使用海藻酸鈉，與BC膜形成複合材料。本文比較了10%與15%兩種不同濃度的CaCl_2交聯劑作為FO膜應用於脫鹽的表現。同時也比較了作為提取液的兩種鹽：2M蔗糖（C_(12)H_(22)O_(11)）以及2M氯化鎂（MgCl_2）。本文根據正滲透系統的實驗室標準，從水通量、鹽通量和脫鹽率幾個面向，分析了製備的椰果正滲透膜（NDC-FO）的表現。15%的CaCl_2相比10%的CaCl_2而言，呈現出高水通量、低鹽通量以及較高的脫鹽率，並且能產生拉力較大的膜。前者在正滲透模塊的吸入點承受壓力，後者則在運行中途破裂。椰果正滲透膜（NDC-FO）的平均接觸角為14.13°，平均厚度為0.159 mm。2M氯化鎂（MgCl_2）作為提取液的表現優於2M蔗糖（C_(12)H_(22)O_(11)）。纖維素三醋酸酯（CTA）的正滲透膜作為基準，被用於橫向比較椰果正滲透膜（NDC-FO）的表現。椰果正滲透膜（NDC-FO）的水通量為4.01 LMH，並且具有88.39%的脫鹽率；而纖維素三醋酸酯（CTA）的水通量為7.97 LMH，並且具有100%的脫鹽率。此研究結果顯示，椰果（nata de coco, NDC）具有一定潛力可成為正滲透（FO）膜原材料。

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