Characterization of Six Hygroscopic Ionic Liquids with Regard to Their Suitability for Gas Dehydration: Density, Viscosity, Thermal and Oxidative Stability, Vapor Pressure, Diffusion Coefficient, and Activity Coefficient of Water Krannich, M.; Heym, F.; Jess, A.; Journal of Chemical & Engineering Data 2016, 61, 1162-1176