Phase equilibria study on bromide-based ionic liquids with glycols and sulfolane. Experimental data and correlation

Abstract

In this work new experimental data on (solid + liquid) phase equilibria of nine binary mixtures composed of bromide-based ILs, namely: 1-ethyl-1-methylmorpholinium bromide, [EMMOR][Br], 1-butyl-1-methylmorpholinium bromide, [BMMOR][Br] and 1-butyl-3-methylimidazolium bromide, [BMIM][Br] with diethylene glycol, triethylene glycol and sulfolane are presented. One of the tested IL, [BMIM][Br] has been synthesized and the structure was confirmed by NMR technique. The experimental SLE data for the tested binary systems have been determined using dynamic method. NRTL and Wilson equations were used to correlate the experimental data. Additionally, the basic characterization of pure ILs have been done; temperature and enthalpy of melting have been determined using DSC technique. The density and dynamic viscosity of pure organic solvents have been determined at wide temperature range. The influence of IL’s structure on mutual solubility with diethylene glycol, triethylene glycol and sulfolane is discussed.