Applicability of different equations in modeling the thermodynamic and transport properties of aqueous and non-aqueous ionic liquid solutions

• Modeling of osmotic coefficient for IL solutions was tested with different models.
• Density values for IL solutions were also modeled.
• Modeling of viscosity for IL solutions was also considered with Eyring’s theory.
• Better results are obtained considering partial dissociation of ionic liquid.
• Better results are obtained for thermodynamic and transport properties by NRF–mNRTL.

Applicability of different electrolyte based models has been tested in correlating the osmotic coefficient values of aqueous and nonaqueous binary ionic liquid solutions considering both the complete and partial dissociation of the ionic liquids. In local composition models the sum of a long-range and a short-range term is used. When the partial dissociation of ionic liquid is considered, the Pitzer–Debye–Hückel and Fowler–Guggenheim equations were used to calculate the long-range electrostatic interaction. In the Fowler–Guggenheim equation, for calculating Debye inverse length the necessary degree of association has been determined from osmotic coefficient data by Chemical Model (CM1). The correlation equations for excess molar volume of the NRTL–NRF, mNRTL, NRF–Wilson and NRF–mNRTL models for ionic liquid or electrolyte solutions were also derived. The performance of these equations was compared with the other available models for correlating the excess molar volume of ionic liquid solutions. Taking into account of complete or partial dissociation of ionic liquids, fitting quality of solution viscosities of various ionic liquids were examined using the Eyring’s absolute rate theory and different electrolyte local composition models and Clegg–Pitzer equations.