Measurement and correlation of the solubilities of luteolin and rutin in five imidazole-based ionic liquids

The solubilities of luteolin and rutin in five pure imidazole-based ionic liquids including 1-butyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide and 1-hexyl-3-methylimidazolium hexafluorophosphate were determined using a dynamic method involving a laser monitoring system under atmospheric pressure. The solubilities of luteolin and rutin in the selected hydrophilic ionic liquids increased as the temperature increased. The experimental data were correlated via a three-parameter empirical equation and the λh equation.