- 期刊
非離子型界面活性劑對略親水酚類化合物萃取技術之研究
Study on Nonionic Surfactant-Based Extraction Technique for Slightly Hydrophilic Phenolic Compounds
摘要
界面活性劑分子是由疏水基及親水基兩部份構成，且在水溶液中，通常可形成所謂的微胞結構。在適當的界面活性劑微胞溶液並經由溫度的改變，界面活性劑水溶液會呈現所謂的雲點現象及相分離的行為。正因如此，可將界面活性劑擁有的這些特殊性質對於水中的有機污染物進行萃取的動作。在本次實驗中，我們利用三種非離子型界面活性劑，亦即Tergitol 15-S-5、Tergitol 15-S-7以及Tergitol 15-S-9，再藉由醇類物質及鹽類的添加，對於九種酚類化合物來進行簡單的萃取，觀察萃取之後的增濃因子為何。除此之外，也對於產生相分離之後的系統進行濃度分析得出兩相濃度的分佈，並研究平衡分佈係數與增濃因子之間的關係。在實驗過程中，使用紫外光偵測器搭配液相層析儀進行定性定量以及兩相平衡之後的濃度分析。從研究的結果中，可以發現增濃因子與平衡分佈係數有某些關聯性。增濃因子下降時，其在界面活性劑兩相之間的平衡分佈係數也會變小，反之亦然。此外，被萃取的酚類化合物平衡分佈係數的對數值與其log Kow值有線性關係，對於在進行萃取之前可利用其log Kow值來大概預知哪些物質的增濃因子。
並列摘要
Surfactant molecules consist of hydrophobic moiety and hydrophilic moiety. In aqueous solutions, surfactant molecules aggregate to form ordered structures, such as micelle. Under proper conditions, micellar solutions can exhibit clouding phenomena and phase separate, which can be applied in extracting trace organic pollutants in water. In this work, three nonionic surfactants, such as Tergitol 15-S-5, Tergitol 15-S-7 and Tergitol 15-S-9, with molecular similarities are employed along with addition of alcohols and electrolytes to carry out preconcentration of nine kinds of phenolic compounds. The concentrations of these phenolic compounds in surfactant-rich and surfactant-lean phases after phase separation are analyzed with the HPLC equipped with UV/Vis detection. It is found that the logarithm of the distribution constants of these phenolic compounds in these two phase systems is a linear function of logarithm of their octanol-water distribution constant, namely log Kow value. This relationship provides great empirical convenience to predict the performance of surfactants in extraction and preconcentration of phenolic compounds.