探討Graphene-TiO2/PVDF中空纖維膜之光、電催化效應對染料溶液降解之影響

Study on the photoelectrocatalytic degradation of organic dye solution using graphene-TiO2/PVDF hollow fiber membrane.

陳冠霖(Guan-Lin Chen)

指導教授 ： 李魁然 ； 洪維松

中原大學/工學院/化學工程研究所/碩士(2016年)

https://doi.org/10.6840/cycu201600594

摘要

本研究使用聚偏二氟乙烯(PVDF)做為紡絲高分子，並添加石墨烯(graphene)、二氧化鈦(TiO2)等無機材料於PVDF鑄膜液中，紡製中空纖維薄膜，並將此中空纖維混合基材薄膜應用於染料降解程序。
研究中利用FESEM、XRD、EDX、TGA、Tensile tester等鑑定儀器針對中空纖維薄膜之無機物分散性與化學特性進行鑑定。研究結果發現隨著二氧化鈦添加量在20 wt%範圍內，二氧化鈦於薄膜中具有良好分散性，經EDX鑑定並沒有團聚現象產生，且隨著無機物添加後，中空纖維薄膜之熱穩定性有著提高的趨勢。
此外，研究中亦探討石墨烯濃度變化對於薄膜之導電性以及機械性質之影響。研究結果發現，中空纖維薄膜之導電性質以及機械強度會隨著石墨烯濃度的增加而上升，於石墨烯濃度為40%的條件下，中空纖維薄膜具備最佳的導電性以及機械強度，其電阻值為394Ω、楊氏模數為51.71MPa。
將此中空纖維混合基材膜應用於染料降解程序，探討光、電催化對染料降解程序之影響。研究結果發現，染料降解效率隨二氧化鈦添加量上升而上升，電催化效果隨供電功率上升而上升。對於二氧化鈦添加量為20%之中空纖維混合基材薄膜而言，在經過7小時UV光照射後，其總有機碳去除率可達到83%；而結合了光、電兩種催化效果下，在相同催化時間下，其總有機碳去除率可達到90%。

關鍵字

中空纖維薄膜 ； 石墨烯 ； 二氧化鈦 ； 光電催化 ； 超過濾

並列摘要

In this study, polyvinylidene fluoride (PVDF) mixed-matrix hollow fiber membranes were prepared with varying amounts of graphene and titanium dioxide (TiO2) particles added into the dope solution. The prepared mixed-matrix hollow fiber membranes’ performance were investigated by discussing the degradation of dye.
FESEM, XRD, EDX, TGA, and Instron measurements were performed to characterize the morphology, mechanical properties and inorganic particles dispersity of the hollow fiber membranes. It was found that an increase in TiO2 content to 20wt%(based on polymer) still provides good dispersion across the membrane structure, and EDX analysis also show the absence of any aggregation. Moreover, an increase in inorganic particle content improves the thermal stability of hollow fiber membrane.
The effect of graphene concentrations on the mechanical property and conductivity of PVDF hollow fiber membranes were also discussed. It was found that increasing the graphene concentration significantly improves the mechanical property and conductivity of the membranes. A graphene concentration of 40% was found to have the optimal conductivity and mechanical property with an electrical resistance of 394Ω and a Young’s modulus is 51.71MPa.
The performance of the graphene-TiO2/PVDF mixed matrix hollow fiber membranes were investigated by discussing the degradation of dye with photoelectrocatalysis. Experimental results showed that with an increase in TiO2 content, the dye degradation rate also increases. In addition, electrocatalytic degradation improved when the duration of power and electricity supplied were increased. The graphene-TiO2/PVDF hollow fiber membranes prepared by adding 20% TiO2 revealed a high removal of total organic carbon (TOC) of 83% under UV irradiation for 7 hours. Lastly, the same membrane showed a 90% removal of TOC under a 7-hour photoelectrocatalytic treatment.

並列關鍵字

PVDF hollow fiber membrane ； Graphene ； TiO2 ； Photoelectrocatalytic ； Ultrafiltration (UF)

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