The use of Differential Scanning Calorimetry (DSC) to characterize phase diagrams of ionic mixtures of 1-n-butyl-3-methylimidazolium chloride and niobium chloride or zinc chloride

The thermal behavior of the BMICl/NbCl5 and BMICl/ZnCl2 mixtures was investigated by DSC and correlated with previous studies using Raman spectroscopy. Combining both results, it was possible to built the phase diagram for these mixtures and suggest the formation of different compounds and the equilibria in the euthetic mixtures. The phase diagram of BMICl and NbCl5 mixture showed that probably only one compound is formed at XNbCl5 = 0.50 (BMINbCl6) and euthetic mixtures are present in the 0 ≤ XNbCl5 ≤ 0.50 composition range. For the BMICl and ZnCl2, four different compounds were detected: (BMI)2(ZnCl4) for XZnCl2 = 0.35; (BMI)2(Zn2Cl6); (BMI)2(Zn3Cl8) and (BMI)2(Zn4Cl10) for XZnCl2 = 0.70, and between these isoplets euthetic mixtures are formed.