Modeling of CO2 solubility in aqueous alkanolamine solutions with an extended UMR-PRU model

Abstract

The phase and chemical equilibria in aqueous alkanolamine solutions containing CO2 is examined in this work. The alkanolamines considered are monoethanolamine (MEA), methyldiethanolamine (MDEA), as well as blends of these two amines. For the vapor-liquid equilibrium calculations, the UMR-PRU model has been extended by incorporating the extended UNIQUAC activity coefficient model to account for the long range electrostatic interactions. The parameters of the UMR-PRU model are either taken from the literature, when available, or determined in this work through fitting vapor-liquid equilibrium experimental data. Very satisfactory results are obtained in all cases examined, which are similar or better than those obtained by other models proposed in the literature, indicating that the UMR-PRU model is able to accurately describe the phase and chemical equilibria in aqueous solutions of alkanolamines and carbon dioxide.