Extractive Distillation Of Tetrahydrofuran-ethanol Azeotrope By Ionic Liquid

Tetrahydrofuran and ethanol are widely used in industrial production. Tetrahydrofuran and ethanol are a important organic chemical raw materials. However, in101.32Kpa, THF and ethanol form a binary azeotrope Department. Effective separation must use special distillation method.This paper is divided into two parts, The first part is a three-component isobaric vapor-liquid equilibrium data, which includes Ionic liquid1-Helsinki3-methylimidazolium tetrafluoroborate ([OMIM] BF4)-tetrahydrofuran-ethanol, it provides the basis for the separation and optimization process. The experimental results show that:added the ionic liquid [OMIM] BF4, deviated the vapor-liquid equilibrium line. Because [OMIM] BF4showed the salt effect, it changed the relative volatility of tetrahydrofuran to ethanol. Common boiling point of Tetrahydrofuran-ethanol eliminated. Add [OMIM]] BF4more, the deviation of the vapor-liquid equilibrium line is greater, Salt effect is more obvious, the relative volatility of tetrahydrofuran to ethanol is more obviously increase. Ideal [OMIM] BF4the extractant proportion is30%.The second part is extractive distillation, when Tetrahydrofuran-ethanol binary systems add the ionic liquid [OMIM] BF4. Study the impact of factors on the separation, which includes different reflux ratio, the flow rate of extractant and extractant, determine optimum process conditions. The experimental results show that, when the reflux ratio R=5, the extractant proportion30%(volume fraction), the extractive agent flow rate4ml/min, THF purity is more than98%, the yield can reach more than81%.