关键词: 离子液体, 汽液平衡, 三乙基铵硫酸氢盐, 乙醇, 水

Abstract: At 101.32 kPa, Isobaric vapor-liquid equilibrium data for the ethanol-water and acetic acid-water system containing the ionic liquid (IL) triethylammonium hydrogen sulfate ([N2,2,2,H]HSO4) were measured in a ellis still. The vapor-liquid equilibrium curve of the ethanol-water system begins to deviate from the line when the mole fraction of [N2,2,2,H]HSO4 reaches 5%. When the mole fraction of [N2,2,2,H]HSO4 is 10% or 20%, the deviation from the line increases. The salt effect of IL changes the relative volatility of water and ethanol, and even leads to the disappearance of the azeotropic point. The more IL is added to the system, the more obvious is the salt effect. The relative volatility of ethanol to water increases as the increases of IL. As a result, it is concluded that [N2,2,2,H]HSO4 can be employed as an entrainer for the extractive distillation of the ethanol-water system.

Key words: ionic liquid, vaporliquid equilibrium, triethylammonium hydrogen sulfate, ethanol, water