Review Of Exiting Group Contribution Methods For Predicting Of The (P,Rho,T) Data Of Even Alkyl Chains (C-2, C-4, C-6, C-8) Imidazolium Ionic Liquids With [Ntf2](-) Anion

A wide literature analysis of exiting Group Contribution Methods (GCM) for predicting the thermophysical properties of ionic liquids (ILs) was analysed. The various possibilities for a linear generalized equation for lattice potential energies/enthalpies of ILs; an approach to estimate thermo-chemical radius and close packed single ion volume data for ions of salt types was discussed. The literature recommendations for "ideal" volumetric behaviour of its, a constant variation of the molar volume with the addition of carbon atoms on alkyl chain were attended during the investigations. The new research applications in the field of hetero-segmented statistical associating fluid theory (hetero-SAFT) to describe (p,rho,T) data of imidazolium its was discussed. The following four ILs with [NTf2](-) anion (F6C2O4NS2):- 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [EMIM][NTf2],- 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [BMIM][NTf2],- 1-Hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [HMIM][NTf2],- 1-Octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [OMIM][NTf2]were examined for these methods and obtained fitting results were discussed. The chemical structure of these its was analysed and divided into the various groups. The molar volume and density of these its, at reference temperature (T = 298.15 K) and ambient pressure (p = 0.101 MPa), is defined as the reference point. As the next step, predicting the density of its across a wide range of temperatures and at reference pressure p(0) = 0.101 MPa were carried out. The measured in our laboratory (p,rho,T) data of these its across a wide temperature range and at high pressures were compared with the predicted values using a GCM and good agreement between them was obtained