Influence of 1-butyl-3-methyl imidazolium bromide, ionic liquid as co-solvent on aqueous solubility of acetaminophen

In this work, influence of 1-butyl-3-methyl imidazolium bromide, ionic liquid on the aqueous solubility of acetaminophen was investigated at different temperatures and mass fraction of ionic liquid. The obtained results reveal that the solubility of acetaminophen was increased by increasing temperature and concentration ionic liquid. Thermodynamic functions of dissolution, mixing and transfer process were calculated by Van't Hoff equation. The obtained results reveal that the main contributor to standard Gibbs free energy of solution process of Acetaminophen in all studied ionic liquid fractions was enthalpy (>0.68). Also standard Gibbs free energy of solution process was decreased (from 15.385 to 11.855 kJ.mol(-1)) by increasing mass fraction of ionic liquid (from 0 to 0.1500). The experimental solubility data of acetaminophen were correlated with the activity coefficient models such as Wilson and NRTL models. The obtained average relative deviation reveals that the Wilson and NRTL models were excellently correlated the experimental solubility data of acetaminophen in aqueous ionic liquid. (C) 2016 Elsevier B.V. All rights reserved.