Separation of ethyl acetate and ethanol by room temperature ionic liquids with the tetrafluoroborate anion

Liquid-liquid equilibrium data are presented for mixtures of 1-ethyl-3-methylimidazolium tetrafluoroborate ([emim]BF4) or 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([C(2)OHmim]BF4) or 1-ethyl-2,3-dimethylimidazolium tetrafluoroborate ([edmim]BF4) or 1-(2-hydroxyethyl)-2,3-dimethylimidazolium tetrafluoroborate ([C(2)OHdmim]BF4) + ethanol + ethyl acetate at 298.15 K. The distribution ratio and selectivity values, derived from the tie line data, show that [C(2)OHmim]BF4 has better extraction capacity than other studied ionic liquids and that a hydroxyl group on the cation and a CH3 group at the 2-position can obviously affect the interaction between the ionic liquid and ethanol. The experimental results show that [C(2)OHmim]BF4 is potentially a candidate to separate ethyl acetate and ethanol by liquid-liquid extraction. The experimental tie lines were correlated with the NRTL equation.