Abstract Three ionic liquids, including 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]), 1-butyl -3-methylimidazolium acetate ([BMIM][Ac]) and 1-hexyl -3-methylimidazolium acetate ([HMIM][Ac]), were selected as entrainers to separate the azeotropic system of acetonitrile + isopropanol. Isobaric vapor liquid equilibrium data of the acetonitrile + isopropanol + ILs ternary systems were determined at 101.3 kPa. The separation performance of the three ionic liquids were analyzed and compared. The nonrandom two-liquid (NRTL) model was used to correlate the experimental data. The addition of [EMIM][Ac] and [BMIM][Ac] could increase the relative volatility of acetonitrile to isopropanol at acetonitrile-rich region, whereas [HMIM][Ac] produced an salting-out effect on acetonitrile at full-concentration region and the effect was more obvious with the increase of its content. All three ILs could break the azeotropic point as their content reach a certain value. The NRTL model was proved to be applicable to the acetonitrile and isopropanol systems containing the three ILs. The separation performance of the three ionic liquids is [HMIM][Ac]>[BMIM][Ac]>[EMIM][Ac].

中文翻译：

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使用乙酸根阴离子作为夹带剂的离子液体分离乙腈 + 异丙醇共沸混合物

摘要 三种离子液体，包括1-乙基-3-甲基咪唑乙酸盐([EMIM][Ac])、1-丁基-3-甲基咪唑乙酸盐([BMIM][Ac])和1-己基-3-甲基咪唑乙酸盐([ HMIM][Ac]) 被选为夹带剂以分离乙腈 + 异丙醇的共沸体系。乙腈 + 异丙醇 + ILs 三元系统的等压气液平衡数据在 101.3 kPa 下确定。对三种离子液体的分离性能进行了分析比较。非随机两液体 (NRTL) 模型用于关联实验数据。[EMIM][Ac]和[BMIM][Ac]的加入可以增加乙腈在富乙腈区域对异丙醇的相对挥发性，而[HMIM][Ac]在全浓度区对乙腈产生盐析作用，且随着其含量的增加作用更明显。当它们的含量达到一定值时，所有三种离子液体都可以打破共沸点。NRTL 模型被证明适用于含有三种离子液体的乙腈和异丙醇系统。三种离子液体的分离性能为[HMIM][Ac]>[BMIM][Ac]>[EMIM][Ac]。