Estudio del equilibrio líquido-líquido de los líquidos iónicos de alquilamonio en la separación de las mezclas azeotrópica etanol e hidrocarburo alifáticos lineales a 298.15 K.

Abstract

The extraction processes of the current chemical plants have to be sustainable and friendly to the environment. Nowadays, chemical industry has a particular interest in these plants namely in the separation of azeotropic mixtures. The components resulting from these separations can be reused again in the industrial processes, which make them more advantageous. The most known process in the separation of azeotropes is the azeotropic or extractive distillation. However, to carry out this kind of process, it is required extreme conditions (high temperatures and high pressures). Therefore, a large amount of energy is necessary to successfully achieve the separation increasing the production costs. In the last decade, ionic liquids have proved their capacity to act as extraction solvents and have emerged as more sustainable alternative to the volatile organic solvents used in the chemical industry in this type of processes. Ionic liquids have also demonstrated their great extraction ability in the separation of azeotropic mixtures. In this work, three ionic liquids were synthesized: 2-hydroxyethylammonium formiate, [N0002(OH)][HCO2]; 2-hydroxyethylammonium propanoate, [N0002(OH)][C2H5CO2]; and 2- hydroxyethylammonium butanoate, [N0002(OH)][C3H7CO2]). All of them were used in the separation of azeotropic mixtures (ethanol + hexane and ethanol + heptane). The liquid-liquid equilibria of these systems were determined at 101.2 kPa and 298.15 K. In addition, the binary parameters of NRTL thermodynamic model were determined with the Aspen Plus V.9 simulator for experimental and literature systems. Finally, a liquid-liquid extraction plant was modelled using the Aspen Hysys V.9 simulator for the same systems in order to determine the efficacy of these ionic liquids as solvent in extraction processes at industrial scale.