ePC-SAFT advanced: A new thermodynamic model for electrolyte solutions

Non-aqueous electrolyte liquid systems become increasingly important for innovative technical processes. However,
modeling such systems is very challenging, and still not all the physical effects are explicitly accounted for in advanced
physics-based thermodynamic models. Thus, such models still rely on extensive parameter fitting over large experimental
data sets. This does often not allow for extrapolation to other conditions as ion parameters that have been fitted to
aqueous electrolyte solutions are not transferable to non-aqueous electrolyte solutions. In this work, a concentrationdependent
dielectric constant was accounted for in the electrolyte theories of Born and Debye-Hückel, which were then
combined with a classical equation of state, Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT). The new
model, called ePC-SAFT advanced, allowed successfully predicting thermodynamic properties of alcohol+salt solutions.
The highlight is that new model parameters were not required and existing ion parameters fitted to aqueous electrolyte
solutions were transferred to the non-aqueous electrolyte solutions.