Development of a New Group Contribution Method Based on GCVOL Model for the Estimation of Pure Ionic Liquid Density over a Wide Range of Temperature and Pressure

A new
group contribution method based on GCVOL model developed
by Elbro et al. in 1991 [Elbro, H. S.; Fredenslund, A.; Rasmussen,
P. Ind. Chem. Eng. Res. 1991, 30, 2576–2582] is proposed for the estimation of
ionic liquids density over a wide range of temperature and pressure.
A total of 102 new groups for ionic liquids were introduced to the
already 60 existing groups revised and proposed in 2003 by Ihmels
and Gmehling [Ihmels, E. C.; Gmehling, J. Ind. Chem. Eng.
Res. 2003, 42, 408–412].
These groups were proposed based on a collection of density data from
literature. The databank contains data of 864 different ionic liquids,
including dicationic and tricationic species, and a total of 21 845
data points, covering a temperature range of 251.62–473.15
K and a pressure range of 0.1–300.0 MPa. An average absolute
relative deviation (%AARD) of 0.83% was obtained, indicating that
our model is able to predict densities of a great variety of ionic
liquids accurately.