Separation Of Ethyl Acetate And 2-Propanol Using Methylimidazolium-Based Ionic Liquids As Entrainers By Extractive Distillation

Ethyl acetate and 2-propanol as important chemical raw materials and organic solvents were widely used in the chemical industry.The mixture of them would inevitably at 101.3kPa form a minimum azeotrope and the extractive distillation technology was generally used to separate them.At present,extractive distillation technology has a general separation performs,so the select the highly effective entrainers plays a crucial role.Recently,ionic liquids(ILs)have become attractive options for entrainers in extractive distillation due to their remarkable physicochemical properties.In this work,ILs were employed as entrainers to separate the ethyl acetate-2-propanol azeotropic system and the effect of ILs on the separation of azeotropic system was studied,which expand the space for the application and development of extractive distillation technology.The ILs [BMIM][Cl] and [BMIM][Ac] were synthesized in our laboratory,the structure,purity and water content of the two ILs were measured.The results showed that two ILs were completely satisfied for experimental requirement.The VLE data of the ethyl acetate(1)+ 2-propanol(2)+ ILs(3)ternary system were measured at 101.3 kPa.The separation performance of the two ILs was discussed and compared in terms of separation factor.The results showed that both ILs could significantly increase the relative volatility of ethyl acetate to 2-propanol and break the azeotropic system,and the [BMIM][Ac] outperforms the [BMIM][Cl].The experimental VLE data were well correlated with the NRTL model,indicating that NRTL model could be applied to this system.The interaction parameters obtained from correlation of experimental data with NRTL model was applied to Aspen plus software to simulated the separation of ethyl acetate-2-propanol with [BMIM][Ac] or [BMIM][Cl].The effects of the number of stage,feed and entrainer location,feed and entrainer temperature,reflux ratio and molar ratio of solvent on the extractive distillation process were studied.Taking the yield and purity rate of ethyl acetate was 99% as an standard and get the feasible opearting conditions in extractive distillation through considering the energy consumption,equipment and operating costs.