Journal of Chemical and Engineering Data, Vol.64, No.11, 4717-4723, 2019
Extraction of Carboxylic Acids from Aqueous Solutions by Using [BMim][NTf2] and Salting-out Agents
Levulinic and lactic acids are important feedstock in a wide range of different industries such as polymer, pharmaceutical, or food manufacture. In this work, a study about levulinic acid and lactic acid recovery from their aqueous solutions was carried out using the hydrophobic ionic liquid (IL) 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonil)imide, [BMim] [NTf2]. Liquid-liquid equilibria data for the ternary systems water + levulinic acid or lactic acid + IL were determined. The obtained experimental data were correlated by using the nonrandom two-liquid (NRTL) equation. An analysis of the influence of the acid structure and the addition of salting-out agents (potassium phosphate, ammonium sulfate, and saccharose) on the phase equilibria, was also carried out. [BMim] [NTf2] was found to be a good extractant for the recovery of levulinic acid and the extraction process was improved by the addition ammonium sulfate.