Solubility of hydrofluorocarbons in phosphonium-based ionic liquids: Experimental and modelling study

• Published in: The Journal of chemical thermodynamics 2014-12, Vol.79, p.184-191
• Main Authors: Sousa, José M.M.V., Granjo, José F.O., Queimada, António J., Ferreira, Abel G.M., Oliveira, Nuno M.C., Fonseca, Isabel M.A.
• Format: Article
• Language: English
• Subjects: CPA EoS; Gas solubility; Hydrofluorocarbon; Phosphonium ionic liquid; Regular solution model
• ISSN: 0021-9614; 1096-3626
• DOI: 10.1016/j.jct.2014.08.001

•Gas solubilities of CHF3, CH2F2 and CH3F in phosphonium-based ILs measured at 1atm.•CHF3, CH2F2 more soluble in [P4,4,4,2][(C2)2PO4] while CH3F is in [P6,6,6,14][Cl].•Solubility of HFC/RTIL systems were modelled using CPA-EoS and RST.•CPA-EoS describes well the experimental data with ARDs of 3.5% using a 2B scheme.•Negative enthalpy and entropy of solvation is observed for all HFC/RTIL systems. In this work, experimental values of gas solubility of hydrofluorocarbons (CHF3, CH2F2 and CH3F) in three room-temperature ionic liquids (RTILs) were determined within the temperature range 288K to 308K and at atmospheric pressure. The RTILs used were trihexyltetradecylphosphonium chloride ([P6,6,6,14][Cl]), tributyl(methyl)phosphonium methylsulfate ([P4,4,4,1][C1SO4]), and tributyl(ethyl)phosphonium diethylphosphate ([P4,4,4,2][(C2)2PO4]). The data gathered have been modelled using two approaches: the Cubic plus Association equation of state (CPA EoS) and the regular-solution theory (RST). The experimental measurements were then discussed critically and the modelling results compared.