Physicochemical Properties And Application Studies On Protic Ionic Liquids Composed Of N-alkylaminium As Cation And Bis (Trifluoromethylsulfonyl) Imide As Anion

Protic ionic liquids（PILs）and aprotic ionic liquids（AILs）are the two major subclasses of ionic liquids（ILs）.Here,we took up PILs,which are composed of protic alkylamines and the anion.There are proton donors and proton acceptors in their structures those lead to PILs stronger polarity because of three dimensional hydrogen-bonded network in the structure of PILs.In addition,the acidity of the Br?nsted acid（anion provider）will govern the degree of proton transfer from the acid to the base.Bis（trifluoromethylsulfonyl）imide acid（HTf₂N）is a strong acid and the proton of acid can be completely transferred to the cation site（alkyleamine）.Therefore,PILs in this study can be regarded as composing of entire anion and cations.In research,the physicochemial properties and applications for the PILs of（HHexen（Tf₂N））,（HHexam（Tf₂N））and（HEt Hexen（Tf₂N））were investigated and the results are summarized in the following three parts.1、Preparations and physicochemical properties of PILsHEt Hexen（Tf₂N）was prepared by the neutralization reaction between the corresponding base and acid.HEt Hexen（Tf₂N）is a colorless liquid at room temperature with the glass transition temperature of-67.73℃and is decomposed at343.3℃.HEt Hexen（Tf₂N）is soluble in polar solvents such as water,methanol,ethanol,acetone,n-butanol and in non-polar solvents such as chloroform,ethylether;poorly soluble in toluene,whereas it is insoluble in n-hexane and petroleum ether.The physicochemical properties such as density,dynamic viscosity and electric conductivity of HEt Hexen（Tf₂N）were studied in the range of T=303.15-353.15 K.The density linearly decreases and dynamic viscosity exponentially decreases while the electric conductivity exponentially increases with increasing the temperature.Temperature dependence of the dynamic viscosity and the electric conductivity of HEt Hexen（Tf₂N）almost follows the Arrhenius equation.2、Water effect on the physicochemical properties of PILsHHexam（Tf₂N）and HHexen（Tf₂N）dissolve a small amount of water even though they are hydrophobic.The solubility of water in PILs are 6.33wt.%（corresponding to w₀=[H₂O]/[PIL]=1.44）and 6.53wt.%（corresponding to w₀=1.65）,respectively.The effect of water content on the physicochemical properties of HHexam（Tf₂N）and HHexen（Tf₂N）were studied in the temperature range of T=303.15–353.15 K.The density linearly decreases,dynamic viscosity exponentially decreases,and the electric conductivity exponentially increases with increasing the temperature or increasing the water content.The relationship between lnη,lnσand1000/T shows liner lines and almost follows Arrhenius equation.The Walden lines for PILs are in the range of△W=0.5±0.2,and close to the line of KCl with increasing the water content,which means the ionicity increases.3、The extraction metal ions using PILsHHexen（Tf₂N）and HEt Hexen（Tf₂N）have chelate amine（ethylenediamine）in their head group,therefore,it is advantageous to trap transition metal ions.In addition,they are hydrophobic PILs.Therefore,it was tried to extract Cu²⁺、Ni²⁺and Co²⁺ions using the present PILs from their aqueous solutions(100 mmol·kg^-1).The analytical result of with inductive coupled plasma emission spectrometry measurements showed that more than 99 wt.%of Cu²⁺、Ni²⁺and Co²⁺ions were moved from the 100mmol·kg^-1aqueous layer to the HHexen（Tf₂N）and HEt Hexen（Tf₂N）layer（of equal volume）.The water contents in the metal-ion containing PILs layer were determined after the extraction and the results were as follows.7.90 wt.%（w₀=2.0）,5.76%（w₀=1.4）and 8.15%（w₀=2.1）for Co²⁺/HHexen（Tf₂N）,Cu²⁺/HHexen（Tf₂N）and Ni²⁺/HHexen（Tf₂N）layers,respectively,and 4.94%（w₀=1.3）,6.39%（w₀=1.72）and4.88%（w₀=1.29）for Co²⁺/HEt Hexen（Tf₂N）,Cu²⁺/HEt Hexen（Tf₂N）and Ni²⁺/HEt Hexen（Tf₂N）layers,respectively.These values are higher than that before the extraction and are lower or a little higher than that in the water-saturated PILs.（w₀=1.65（6.53%）and w₀=2.67,（9.58%）for HHexen（Tf₂N）and HEt Hexen（Tf₂N）,respectively）...