Determination of Distribution Coefficients in 1-Ethyl-3-Methyl Imidazolium Chloride-Methylimidazole Mixtures by Zone Melting

The first experimental results concerning the differential distribution coefficient, k_diff, for crystallization of 1-ethyl-3-methyl imidazolium chloride (EMIMCl) out of EMIMCl- methylimidazole (MIM) mixtures (5 wt % MIM) are presented. The mixture was purified using the zone melting technique at a fixed crystallization rate of 1.44 mm/h. For quantification of the MIM content after purification an analytical method consisting of the combination of ion chromatography and UV/Vis detection was developed. A distribution coefficient of k_diff = 0.2 was found.