離子液體水溶液比熱及電導度量測研究

Measurement of Heat Capacity and Electrical Conductivity of Aqueous Solutions of Ionic Liquids

林姵吟(Pei-Yin Lin)

指導教授 ： 李夢輝

中原大學/工學院/化學工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200900860

摘要

本實驗量測四個離子液體水溶液之熱容量與電導度，主要量測系統如下: [Bmim][CF3SO3] (1-butyl-3-methylimidazolium trifluoromethanesulfonate) + H2O, [Bmim][MeSO4] (1-butyl-3-methylimidazolium methylsulfate) + H2O, [Emim][CF3SO3] (1-ethyl-3-methylimidazolium trifluoromethanesulfonate) + H2O, [Emim][C2H5SO4] (1-ethyl-3-methylimidazolium ethylsulfate) + H2O；主要利用示差掃描熱量計(Differential Scanning Calorimeter, DSC)量測熱容量，溫度範圍為303.2–353.2 K，其不確定性為  0.015 (kJkg-1K-1)；並利用電導度計量測電導度，溫度範圍為293.2–353.2 K，其不確定性為  0.001 (Sm-1)。本實驗研究值與文獻值有良好之符合性，實驗所量測之離子液體比熱值與電導度值以溫度與濃度為變數做迴歸計算，熱容量值是利用 代入Redlich-Kister equation予以迴歸計算；電導度值是使用其他學者所提出之模式與修正模式來迴歸計算，比較其迴歸結果再加以討論，迴歸計算值與實驗值亦有良好之符合性。本研究成果可作為工程設計基礎數據與計算依據。

關鍵字

電導度 ； 比熱 ； 離子液體

並列摘要

The heat capacities and electrical conductivities of four binary aqueous solutions of ionic liquids had been measured. The investigated ionic liquid systems were as follows: [Bmim][CF3SO3] (1-butyl-3-methylimidazolium trifluoromethanesulfonate) + H2O, [Bmim][MeSO4] (1-butyl-3-methylimidazolium methylsulfate) + H2O, [Emim][CF3SO3] (1-ethyl-3-methylimidazolium trifluoromethanesulfonate) + H2O, and [Emim][C2H5SO4] (1-ethyl-3-methylimidazolium ethylsulfate) + H2O. The heat capacities were measured over the temperature range from (303.2 to 353.2) K using a differential scanning calorimeter (DSC). The electrical conductivities were measured using a commercial conductivity meter in the temperature range from (293.2 to 353.2) K. The estimated uncertainties of heat capacity CP and electrical conductivity  measurements were  0.015 (kJkg-1K-1) and  0.001 (Sm-1). The heat capacities and electrical conductivities were presented as a function of temperature and composition. For the studied aqueous ionic liquid systems, the excess molar heat capacity values were represented by typical Redlich-Kister expansion and the  values were correlated using equations from other investigators and its modified forms. The correlations give satisfactory results. The heat capacities and electrical conductivities presented in this work are, in general, of sufficient accuracy for most engineering-design calculations.

並列關鍵字

heat capacity ； ionic liquid ； electrical conductivity

參考文獻

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