Modelling thermodynamic properties of iodoalkane plus alkane systems usinggroup contribution models

The experimental data available in the literature for the binary systems 1- iodoalkane and alpha,omega -diiodoalkane with alkanes are used to determine the interaction parameters of the iodine and methyl or methylene groups of the Nitta-Chao equation-of-state group contribution model and of three ver sions of the UNIFAC model due to Tassios et al., Larsen et al. and Gmehling et al. The results for the thermodynamic properties obtained using the new parameters of the three versions of the UNIFAC and Nitta-Chao models are c ompared with those of the DISQUAC model. Liquid-liquid equilibria data of a lpha,omega -diiodoalkane + alkane mixtures were used to check the obtained interaction parameters. An analysis of the dispersive and non-dispersive in teractions is presented with the estimation of the changes of the mean numb ers of contacts between the iodine, methyl and methylene groups during the mixing process.