離子液體靜相在油品及副產物的分析與固相微萃取的應用

許瓊儀(Hsu, Chiungyi)

指導教授 ： 魏國佐

國立中正大學/理學院/化學暨生物化學系/碩士(2012年)

摘要

本研究乃探討離子液體於氣相層析、超臨界流體層析及固相微萃取的應用。
由於離子液體的高黏滯度與濕潤性，可在毛細管壁形成薄膜，且其良好的熱穩定性，所以離子液體可以作為氣相層析靜相。研究的第一部分混和不同比例的1-(p-Vinylbenzyl)-3-methyl imidazolium bis(trifluoromethyl-sulfonyl)imide（[VBMI] [NTf2]）及 1,9-Di(3-vinylimidazolium)nonane bis(trifluoromethyl-sulfonyl)imide（[C9(vim)2][NTf2]2），進行交聯反應形成離子液體聚合物做為氣相層析靜相；當操作溫度高達380℃時，理論板數仍維持在每米1000左右，此顯示離子液體聚合物做為氣相層析靜相的高熱穩定性。利用此靜相分離九種脂肪酸酸甲酯，結果顯示 [VBMI][NTf2] 所提供的π-π作用力，可成功分離含有不飽和鍵的脂肪酸甲酯。
研究的第二部分則將Octyl imidazolium bromide ( [OIM][Br] ) 修飾於 Silica gel 上，作為超臨界流體層析靜相來分離四種維他命E化合物；實驗上探討壓力、溫度、及修飾劑對分離能力的影響，結果顯示離子液體的氫鍵接收能力與π-π作用力等多重模式可以將維他命E化合物完全分離。
研究的第三部分混合[C9(vim)2][NTf2]2及1-Butyl-3-vinylimidazolium bis(trifluoromethyl-sulfonyl)imide ( [BVIM][NTf2] ) 反應成為聚合物後，做為固相微萃取靜相來萃取水溶液中的 BTEX、苯酚類及爆炸物；實驗上比較塗覆前、後進行聚合反應製備微萃取靜相對萃取效能的影響。結果顯示塗覆離子液體後再進行聚合反應所製備的微萃取靜相，可提升150% 的萃取率；此外，在離子液體中添加多壁奈米碳管 ( Muliti-Wall Carbon Nanotubes，MWCNTs ) ，利用奈米碳管的π-π作用力，可加強靜相和分析物的作用力，可進一步提升微萃取靜相整體的吸附量約75%。

關鍵字

離子液體

並列摘要

In this work, ionic liquids were employed as the stationary phases of gas chromatography (GC), supercritical fluid chromatography (SFC) and solid phase microextraction (SPME).
Owing to their high viscosity and high wetting ability of ionic liquids, they could be coated onto the inner wall of fused silica capillaries and then used as the stationary phases of GC. In the first part of this research, polymerized ionic liquid-based stationary phases were prepared by cross-linking different proportions of 1-(p-vinyl benzyl)-3-methyl imidazolium bis(tri fluoromethylsulfonyl)imide ([VBMI][NTf2]) and 1,9-di(3-vinylimidazolium)nonane bis(trifluoromethylsulfonyl)imide ([C9(vim)2][NTf2]2). When the working temperature was heated up to 380 ℃, the numbers of theoretical plates still reached 1000 (plates/m) to indicate the thermal stability of the stationary phase. With a proper composition of polymerized ionic liquid, we could successfully separate nine fatty acid methyl esters that contain different unsaturated isomers, due to the π-π interaction provided by [VBMI][NTf2].
In the second part of this research, we modified silica gel with Octyl imidazolium bromide ([OIM][Br]) to form the SFC stationary phase. The effects of the pressure, temperature, and organic modifiers on the retention behavior of vitamin E mixture of SFC were examined. Since this stationary phase can provides multi-interactions, such as the hydrogen bonding and the π-π interaction, we could separate four vitamin E isomers of palm oil successfully.
In the finial part of this research, the polymer of [C9(vim)2][NTf2]2 and 1-Butyl-3vinylimidazolium bis(trifluoromethyl-sulfonyl)imide ( [BVIM][NTf2] ) were employed as the stationary of SPME to extract the BTEX, phenols and explosives in waters. The results show that the order of coating and polymerization process affects on the extraction efficiency of the SPME fiber. Coating ionic liquid and then polymerizing the ionic liquids increases the fiber extraction efficiency 150% over than that of polymerization the ionic liquid and then coating the fiber. It is worth to note, when we added multi-wall carbon nanotubes (MWCNTs) into the ionic liquid composite of the fiber, the extraction efficiency was further increased by 75%. This may be due to the π-π interaction induced by MWCNTs in the ionic liquid composite.

並列關鍵字

ionic liquid

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