| Ionic liquid(IL) provides a new entrainer for improving the extractive distillation technology.In this paper,we choose ethanol,1-propanol,2-propanol and tert-butyl alcohol four systems containing water to study the selective of some ionic liquids.Also we measured vapor-liquid equilibrium (VLE) data for the ternary systems congtaning ionic liquid and established thermodynamic modeling of IL-containing system,which propose the basic data sets and design foundation for the design of extractive distillation.In this work,we studied the selective of ILs for the systems(water + ethanol + eight ILs and water + tert-butyl alcohol + six ILs),and discussed the influence of ionic liquids with different cations and anions for activity coefficient and relative volatility Several ILs were investigated,cation including[emim]+,[bmim]+,[hmim]+;anion including[BF4]-,[N(CN)2]-, [OAc]-,[Cl]-.Results showed that,the effect of ionic liquid mainly depends on anion.Considering the relatively low viscosity and melting point,with good selective,this IL with[OAc]-might be favorable candidate as entrainer for potential industrial application.Also we measured vapor-liquid equilibrium(VLE) data for a ternary system water(1) + ethanol(2) +[hmim][Cl](3) at p = 100 kPa.Six data sets of forty-eight data points were obtained,which were regularly distributed at w3 = 0.1 to 0.8,in an interval of 0.1,and at x'2 = 0.1,0.2,0.4, 0.6,0.8,and 0.98.And also in this paper,we studied the establishment of thermodynamic modeling and the prediction of ternary system containing IL.Results indicated that,the NRTL equation was used for correlation and revealed adequate for the ternary system in the experimental composition range.The quality of correlation appeared to be sensitive to the parameters used for water + ethanol.Because of higher molecular weight and non-volatile for ionic liquid,VLE of a ternary system containing IL can be correlated and predicted by binary system datas,but it would have larger deviation.By correlating the two data sets,respectively at x'2 = 0.1 and 0.98,all of the six data sets were reproduced satisfactorily,withδT = 0.49 K andδy = 0.0042.Futher,we studied the VLE behavior of five IL-containing systems (water + ethanol / 2-propanol / 1-propanol + bmimCl,water + ethanol / 2-propanol +[bmim][OAc]).Results showed the e-NRTL equation is also suitable for the ternary system containing IL as NRTL equation.VLE of ternary systems can be preferably predicted by correlation of data at x'2 = 0.1 and x'2≈0.9.In this paper,we also dicussed that the influence of different alcohols and ionic liquids containing different anions for activity coefficients of volatile component and relative volatility.
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