Ionic liquids have been the object of intense interest from both academic and industrial research groups aiming at a wide range of applications in novel processes and products. The knowledge of their thermophysical properties, or the ability to estimate them, is often required for the design of these processes and products. However, experimental data for many properties are in short supply and often contradictory among various sources available. Based on experimental data collected from the literature, predictive group contribution models were developed after a critical analysis of the data for various thermophysical properties, viz. density, viscosity, surface tension, speed of sound, refractive index, heat capacity, electrical conductivity, thermal conductivity, isobaric expansivity, and isothermal compressibility, of various families of ionic liquids. The results of the proposed models show average absolute relative deviations generally of the same orderas the experimental accuracy of the data itself. These rapid and facile predictive models are very easy to use, can provide predictions of property values for the new ionic liquids, and also allow them to be extended to new groups of cations and anions as further data become available.
