Data from: Synthesis and investigation of physicochemical properties of dicationic ionic liquids

A series of dicationic ionic liquids (ILs) including [C4(MIM)2] [PF6] 2,
[C5(MIM)2] [PF6] 2, [C6(MIM)2] [PF6] 2and [C4(PYR)][PF6]2 were
synthesized. Their thermal stability and melting points were analyzed. It
was found that dicationic ILs presented important implications in the
design of homogeneous and heterogeneous system with water. A homogeneous
system of dicationic ILs with water could be formed at a relatively high
temperature and then a heterogeneous system was formed when the solution
was cooled to a low temperature. The recovered ILs by altering the
temperature were obtained in high yields of [C46]2(0.98 g),
[C5(MIM)2][PF6]2 (0.97 g), [C6(MIM)2][PF6]2 (0.98 g) and [C4(PYR)2][PF6]2
(0.94 g). In the other hand, [C4(MIM)2][PF6]2 and [C5(MIM)2][PF6]2
exhibited good solubility in acetonitrile and acetone. A homogeneous
system could be achieved with imidazolium-based ILs with a relatively low
amount of water and acetonitrile at room temperature. All of the
properties of dicationic ILs have a strong correlation with the nature of
dications, the linkage chain and the symmetry of dications. Dicationic ILs
may provide new opportunity for some specific applications in order to
enable the effective separation and isolation of products.