Measurement and correlation of isobaric binary vapor-liquid equilibria for water and 2-propanol each with 1-butyl-1-methypyrrolidinium chloride and 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate

Abstract

Binary vapor-liquid equilibria (VLE) for water and each of 1-butyl-1-methypyrrolidinium chloride ([BMPy][Cl]) and 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate ([BMPy][OTf]), and 2-propanol with the same ionic liquids are experimentally measured and reported at 50, 75, 100 kPa. The VLE data were experimentally generated using a two-phase circulation ebulliometer. The experimental results are then modeled using two well-known liquid phase models, i.e., the Non-Random, Two-Liquid model (NRTL), and the modified one-parameter NRTL model (M1NRTL), which utilizes the critical properties to predict the binary interaction parameters. Based on the observed boiling point elevation, it is concluded that, in comparison with [BMPy][OTf], [BMPy][Cl] has a higher interaction with both solvents. It was also found that the NRTL model well describes the experimental data for both solvents, with a root-mean-square deviation (RMSD) < 0.015, while the M1NRTL model suffers especially for the water-containing system, with an RMSD as high as 0.1.