Vapor-Liquid Equilibria of Water plus Alkylimidazolium-Based Ionic Liquids: Measurements and Perturbed-Chain Statistical Associating Fluid Theory Modeling
authors Passos, H; Khan, I; Mutelet, F; Oliveira, MB; Carvalho, PJ; Santos, LMNBF; Held, C; Sadowski, G; Freire, MG; Coutinho, JAP
nationality International
journal INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
keywords INFINITE DILUTION MEASUREMENTS; DIRECTIONAL ATTRACTIVE FORCES; AQUEOUS BIPHASIC SYSTEMS; 2ND VIRIAL COEFFICIENTS; EQUATION-OF-STATE; ORGANIC SOLUTES; THERMODYNAMIC PROPERTIES; PRESSURE MEASUREMENT; PHYSICOCHEMICAL PROPERTIES; BINARY-SYSTEMS
abstract The industrial application of ionic liquids (ILs) requires the knowledge of their physical properties and phase behavior. This work addresses the experimental determination of the vapor-liquid equilibria (VLE) of binary systems composed of water + imidazolium-based ILs. The ILs under consideration are 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium thiocyanate, 1-butyl-3-methylimidazolium tosylate, 1-butyl-3-methylimidazolium trifluoroacetate, 1-butyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium methanesulfonate, and 1-butyl-3-methylimidazolium acetate, which allows the evaluation of the influence of the IL anion through the phase behavior. Isobaric VLE data were measured at 0.05, 0.07, and 0.1 MPa for IL mole fractions ranging between 0 and 0.7. The observed increase in the boiling temperatures of the mixtures is related with the strength of the interaction between the IL anion and water. The Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) was further used to describe the obtained experimental data. The ILs were treated as molecular associating species with two association sites per IL. The model parameters for the pure fluids and the binary interaction parameter k(ij) between water and ILs were determined by a simultaneous fitting to pure-IL densities, water activity coefficients at 298.15 K and VLE data at 0.1 MPa. Pure-IL densities, water activity coefficients, and VLE data were well described by PC-SAFT in broad temperature, pressure, and composition ranges. The PC-SAFT parameters were applied to predict the water activity coefficients at infinite dilution in ILs, and a satisfactory prediction of experimental data was observed.
publisher AMER CHEMICAL SOC
issn 0888-5885
year published 2014
volume 53
issue 9
beginning page 3737
ending page 3748
digital object identifier (doi) 10.1021/ie4041093
web of science category Engineering, Chemical
subject category Engineering
unique article identifier WOS:000332684500033

Sponsors

1suponsers_list_ciceco.jpg