293.15K时乙腈+水+[Hmim]Cl三元系统及其二元系统的折光率测定与关联

efractive Indices for Acetonitrile+Water+[Hmim]Cl and Its Binary Systems at 293.15 K

主要通过折光率来研究离子液体对乙腈+水系统物理性质的影响。采用折光仪测定了乙腈+水+[Hmim]Cl(1-己基-3-甲基咪唑氯盐)三元系统及相应的乙腈+水、水+[Hmim]Cl、乙腈+[Hmim]Cl二元系统在293.15 K时的折光率,并获得了这些系统的过量折光率,建立了折光率与组成间的经验关系。结果表明,在全部浓度范围内过量折光率均为正值,且乙腈+水的折光率随组成变化出现极大值,而水+[Hmim]Cl、乙腈+[Hmim]Cl的折光率均随离子液体组成的增加而增加。用Redlich-Kister、Cibulka模型和Singh模型分别关联了二元和三元系统的过量折光率,证实可采用Kohler方程估算三元系统的折光率。

This work investigated the effect of ionic liquid on the physical properties of acetonitrile ＋ water with the refractive indices,which were measured for the ternary system（acetonitrile ＋ water ＋ Cl（1-hexyl-3-methylimidazolium chloride）） and its binary systems（acetonitrile ＋ water,water ＋ Cl and acetonitrile ＋ Cl） at 293.15 K by a refractometer.The excess refractive indices of the mixtures were obtained and the relationship of refractive indices with mole fractions was established with an empirical model.It was shown that the excess refractive indices were positive over the whole range of compositions,and there was a maximum for the refractive indices over the range of the investigated mole fraction in acetonitrile ＋ water and the refractive indices in water ＋ Cl and acetonitrile ＋ Cl increased as the mole fraction of the ionic liquid increased.Furthermore,the excess refractive indices for the binary and ternary systems were fitted to the Redlich-Kister,Cibulka and Singh equations,respectively.As a result,the Kohler equation can successfully predict the refractive indices for the ternary system.