| 摘要: | 本篇論文主要是合成具有雙官能基的中孔洞材料及其應用，共分為兩個部分，第一部分利用 Brij 76 (C18H37(OCH2CH2)10OH) 作為模板試劑，1,4-bis(triethoxysilyl)benzene (BTEB) 與Carboxyethylsilanetriol sodium salt (CES) 為共同矽源，在酸性條件下合成具有苯環與羧酸官能基之中孔洞材料，之後利用 48 % H2SO4 於高溫下裂解模板 Brij 76，即可得孔壁具有苯環排列且表面修飾上羧酸官能基之中孔洞材料，而羧酸官能基含量可高達80 %，且仍具有良好之結構規則度。以上實驗利用 X-ray 粉末繞射、固態核磁共振光譜、熱重分析儀、等溫氮氣吸脫附、穿透式電子顯微鏡及掃描式電子顯微鏡等儀器鑑定材料的特性，藉此瞭解在不同 CES 含量比例之孔洞性質變化趨勢，且對植入的羧酸官能基定量。 而第二部份則是利用上述所合成的中孔洞材料 (簡稱為BC-X，X指 [CES/(CES+BTEB)]之莫耳比例) 應用於吸附染料亞甲基藍(Methylene blue)。研究吸附過程中影響吸附的因素，包括孔洞材料中羧酸官能基的負載量、亞甲基藍吸附系統的溫度及pH值等。由實驗結果可得知，由於孔洞材料的高表面積，羧酸官能基的良好親和力及苯環間 pi-pi 作用力， BC-X系列之中孔洞材料對於亞甲基藍具極佳吸附效果，且具良好的重複使用性，故BC-X系列之中孔洞材料對移除廢水中的亞甲基藍具應用潛力。由吸附實驗結果顯示 Langmuir 等溫吸附模式比 Freundlich 等溫吸附模式更適合描述 BC-X 吸附亞甲基藍的系統，顯示本實驗的吸附形式為單層吸附模式。The thesis is divided into two parts. In the first part, carboxylic acid functionalized mesoporous benzene-silica (BC-X materials, X refers to the [CES /(CES + BTEB)] molar ratio) have been synthesized with Brij 76 as the structure-directing agent under acidic conditions via co-condensation of 1,4-bis(triethoxysilyl)benzene (BTEB) and carboxyethylsilanetriol sodium salt (CES). The BC-X materials are ordered and uniformed mesoporous with a high loading of carboxylic acid groups (up to 80 mol% based on silica). In this study, a varief of techniques was adopted to characterized the BC-X materials, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), 13C CP-MAS NMR, 29Si MAS NMR , nitrogen sorption measurements, thermogravimetric analyzer (TGA), Fourier transform infrared spectrometer (FTIR) and powder X-ray diffraction (XRD). In the second part, the BC-X samples with high loadings of carboxylic group is therefore acted as adsorbents for the removal of methylene blue. The adsorption process is carefully studied with various systematic factors, including the loading amount of CES, the quanity of methylene blue, temperature and pH of adsorption system. Due to the high surface area, good affinity of arboxylic groups and pi-pi interaction of benzene rings, the BC-X materials exhibits excellent performance on methylene blue adsorption. The experimental data for the adsorption were analyzed using Freundlich and Langmuir isotherm models. It is found that the Langmuir equation provides an accurate description of these adsorption data, suggesting that monolayer adsorption occurred in all cases of the performed sorption processes. |
