Binary mixtures of HMIMPF6 ionic liquid and n-butyl acetate cosolvent in the extraction of acetone from aqueous solutions

• Published in: Chemical engineering communications Vol. 205; no. 8; pp. 1096 - 1104
• Main Authors: Mohammadi Sarab Badieh, Marjan, Saien, Javad
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 03.08.2018; Taylor & Francis Ltd
• Subjects: Acetone; Activity coefficients; Binary mixtures; Cosolvent; extraction; Ionic liquids; Ions; Liquid-liquid equilibrium; Liquid-liquid extraction; NRTL model; physical properties; Quaternary systems; Solvents; Viscosity
• ISSN: 0098-6445; 1563-5201
• DOI: 10.1080/00986445.2018.1433665

A remarkable disadvantage of pure ionic liquids, to be used as a solvent in different processes, is their high viscosity and density. Here, n-butyl acetate was used as a cosolvent in the liquid-liquid system of {water + acetone + 1-hexyl-3-methylimidazolium hexafluorophosphate (HMIMPF 6 ) ionic liquid}. Mixtures of the ionic liquid and the cosolvent were used as the organic phase to extract acetone from aqueous phase. A drastic decrease in viscosity and a significant decrease in density of the ionic liquid were achieved in the presence of cosolvent. Accordingly, the liquid-liquid equilibrium of different provided systems was studied under temperature of 298.2 K and atmospheric pressure of 81.5 kPa. Binary phase regions and corresponding tie-lines and binodal curves were obtained for ternary and quaternary systems. Results show the extension of the binodal solubility region as well as enhancements up to 41.8% in the acetone separation factor. The tie-line data consistency was confirmed by the Othmer-Tobias and the Hand equations. Moreover, the nonrandom two-liquid model of activity coefficient was applied satisfactorily to reproduce the equilibrium data with a root-mean-square deviation of only 1.95%.