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標題: 現地溶膠-凝膠法製備PPO-Silica混合基材薄膜對氫分離與二氧化碳捕獲之應用
Preparation of PPO/Silica mixed matrix membrane through in-situ sol-gel method for H2 purification and CO2 capture
作者: 莊國良
Chuang, Kuo-Liang
關鍵字: 氣體分離;gas separation;二氧化碳;混合基材薄膜;現地溶膠-凝膠法;熱處理;carbon dioxide;mixed matrix membranes;in-situ sol-gel method;heat treatment
出版社: 環境工程學系所
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混合基材薄膜(Mixed matrix membranes,MMMs)一直是近年來廣受研究的一種新興材料,主要透過有機與無機兩種材料特性的結合,具有良好的機械性、熱性質和優異的滲透分離效能。然而,無機與有機材料間的結合情形是影響整體薄膜滲透與分離效能的重要因子,因此如何使兩相間產生理想的黏著性(adhesion)為近年來的研究重點。故本研究將利用現地溶膠-凝膠程序與後熱處理方式來製備PPO-silica的混合基材薄膜以改善兩相 的黏著情形。研究中亦將探討無機材silica的添加量對薄膜物理特性之影響,並透過電子顯微鏡(FESEM)、熱重分析儀(TGA)、X光繞射分析儀(XRD)及傅立葉紅外線轉換光譜儀(FTIR),觀察混合基材薄膜之外觀結構、熱穩定性、結晶結構和官能基等特性,並透過單一氣體滲透實驗進行效能評估。

Mixed matrix membranes (MMMs) are considered as a potential candidate for membrane separation techniques due to their attractive mechanical strength, thermal stability and superior perm-selectivity properties. In general, the MMMs consist of organic polymer and inorganic particle phases. However, the permselectivity properties of MMMs are greatly influenced by both the dispersing degree of nano-particles in the continuous phase (polymers) and the interfacial adhesion between the inorganic and organic components. Therefore, the problems MMMs faced are challenging to achieve an optimized interface structure and forming composite membrane with an ultrathin and defect-free mixed matrix skin by novel preparation technology.
In this study, the PPO-silica MMMs was synthesized through in-situ sol-gel method, and the effect of silica loading weight and heat treatment on the gas separation performance was investigated. The gas permeation was studied and the morphological, crystalline structure, thermal stability, and functional group of MMMs was obtained using SEM, TGA, XRD, and FTIR, respectively.
The results indicate that using in-situ sol-gel method to synthesize PPO-silica MMMs is beneficial for improving nano-filler dispersion. The permeability towards H2, CO2, O2, N2, and CH4 can be enhanced without increasing selectivity slightly. Further, an improvement in adhesion between both phase and crystal structure of the polymer matrix has been observed by the recrystallization process after heat treatment, which is beneficial for diffusivity of lower molecular weight of gas components. Thus, an enhanced H2 permeability from 51.26 to 117.78 GPU and the H2/CO2 separation ratio ca. 3.6 was observed from 5 wt. % PPO-silica MMMs.
其他識別: U0005-1906201314232600
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