隨著環保意識的高漲，已具有回收容易，揮發性低，不易燃等特性的 ” 綠色溶劑 “ 離子熔液來取代傳統易燃、有毒、及揮發性高的有機溶劑是必然的趨勢。本研究是採用[emim][PF6]、[bmim][PF6]為離子熔液，針對離子熔液和水的兩元系統的相平衡作為探討離子熔液中對自然界的影響，而藉由測量[emim][PF6]在1-octanol與水的液液相平衡中的三相圖，進而探討離子熔液的正辛醇/水分配係數（1-octanol/water partition coefficient ），得以作為綠色溶劑的參考此外，為了了解[emim][PF6] 在有機醇與水的系統中的三相平衡，還選用N-butyl Alcohol 、以及ethanol當有機溶劑，測量其離子熔劑在其相平衡的分布。
研究在離子熔液與水的液液平衡中，溫度恆溫在30℃、40℃、50℃下，使用UV量測水相中離子熔液的濃度，Karl-Fischerh測量離子熔液相中水的濃度，如此，得到離子熔液在水中的飽和溶解度。而離子熔液在水與1-octanol的液液相平衡中的分布係數，則用TGA測量水相及1-octanol相中離子熔液的濃度；UV測量水相中離子熔液的濃度；Karl-Fischer測量1-octanol中含水的濃度。此外，為了了解[emim][PF6] 在有機醇與水的系統中的三相平衡，還選用N-butyl Alcohol、以及ethanol當有機溶劑，測量其離子熔劑在其相平衡的分布。

首先，在離子熔液與水在各個溫度下的液液相平衡中，得到離子熔液在水中的溶解度比預估的大的多，也就是說離子熔液可能會藉由溶解在水中流失到自然界中。因此，接下來探討離子熔液的正辛醇/水分配係數，而在水相中分別用TGA以及UV來分析離子熔液的濃度，得到的數據相當的吻合。GC分析1-octanol的濃度。在1-octanol相的部分則用Karl-Fischer分析水的含量以及用TGA分析油相中離子熔液的濃度。但是在水相中的1-octanol上無法準確得到，此外用TGA分析離子熔液的部分，因為離子熔液在高溫下有可能產生裂解的情形，仍然有相當的問題。

雖然目前尚無法建立相當準確的數據來計算離子熔液的正辛醇/水分配係數，但從TGA的分析可以估計離子熔液在油相的溶解度是相當小的，也就是說離子熔液的正辛醇/水分配係數相當小，推測將是很有潛力的綠色溶劑。

Room temperature ionic liquid, which are nonvolatile, inflammable, and good solvation power, has attracted a lot of recent attention as a "green solvent" alternative. In this work, solid-liquid and liquid-liquid equilibria of [emim][PF6]+water and liquid-liquid equilibria of [bmim][PF6]+water are studied. UV was used to measure the solubility of ionic liquid in water phase. Karl-Fischer was used to measure the solubility of water in ionic phase. The solubility of [bmim][PF6] in water phase (2.36+0.08 wt% at 303 K to 3.67+0.2 wt% at 323 K) is less than that of [emim][PF6] and increases with increasing temperatures. The solubility of water in liquid [bmim][PF6] phase changes from about 2.70+0.03 wt% at 303 K to 3.70+0.03wt% at 323 K.
While solubilities of ionic liquids in water are small, they are far from negligible. Hence cautions must be taken to prevent lost into environment when these chemicals are used. So we are conducting experiments to measure the partition of ionic liquids between water and biocompatible organic liquids such as 1-octanol and other alcohols. UV and TGA was used to measure the solubility of ionic liquid in water phase. GC was used to measure the solubility of 1-octanol in water phase. Karl-Fischer was used to measure the solubility of water in 1-octanol phase. TGA was also used to measure the solubility of ionic liquid in 1-octanol phase. But the solubility of 1-octanol in water phase and the solubility of ionic liquid in 1-octanol phase remained to be investigated.

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