Determination of three physical properties of quinoline ionic liquids with hexafluorophosphate

Densities of one acidic ionic liquid (IL) Quinolinum hexafluorophosphate ([HBpy][PF 6 ]), and four neutral dicationic ionic liquids (ILs) based on quinoline and hexafluoro-phosphate and linked with poly(ethylene glycol) (PEG): ([PEG 200 -DIL][PF 6 ] 2 , [PEG 400 -DIL][PF 6 ] 2 , [PEG 800 -DIL][PF 6 ] 2 and [PEG 1000 -DIL][PF 6 ] 2 ) were determined. In addition, the solubilities of six ILs in six lower alcohols, water, acetonitrile and diethyl ether were measured at 288.15 K; and the hydroscopicity of above five ILs were measured at the temperature of 298.15 K and relative humidity of 79% for 24 h. Densities of five ionic liquids were determined between 283.15 and 333.15 K. Then the densities of five binary system (ILs/acetonitrile) were explored between 283.15 and 333.15 K, the type of the ionic liquid, the concentration of five ILs in CH 3 CN, and the effect of temperature on the binary systems, were correlated with the measured data.