tert

-butanol and ethyl acetate

as fuel additives and oxygenated fuels

can improve fuels quality and reduce exhaust emissions. Therefore

the recovery of these compounds from azeotropic systems is of great significance. Ionic liquids (ILs) are promising green solvents for separating azeotropic systems. In this study

an efficient extraction strategy based on 1-butyl-3-methylimidazolium acetate ([Bmim

]

[AC

]

) is proposed. The mechanism by which ILs enable the separation of binary alcohol-ester azeotropes was revealed by evaluating the lowest conformational energy through combining an independent gradient model based on the Hirshfeld partition (IGMH) and frontier molecular orbitals

to preliminarily screen the extractants. The range of extractants was further reduced by a vapor–liquid phase equilibrium (VLE) experiment

and a modeling method for separating the alcohol–ester system and recovering the solvent using [Bmim

]

[AC

]

and 1-ethyl-3-methyl-3-imidazolium acetate ([Emim

]

[AC

]

) is established. Under the optimal operating conditions

the use of [Bmim

]

[AC

]

can reduce the total annual cost (TAC) per year by 17.78%

and the emissions of CO

2

SO

2

and NO can be reduced by 10.86%. In this study

a comprehens

ive method for screening extractants is proposed

and the simulation process is optimized in combination with the economic and environmental impact. The results have important guiding significance for realizing efficient

energy-saving

and green azeotropic separation systems in industry.