Kinetics of the reactive absorption of carbon dioxide in high CO2-loaded, concentrated aqueous monoethanolamine solutions

The kinetics of the reaction between carbon dioxide and high CO2-loaded, concentrated aqueous solutions of monoethanolamine (MEA) were investigated over the temperature range from 293 to 333 K, MEA concentration range from 3 to 9M, and CO2 loading from similar to 0.1 to 0.49 mol/mol. The experimental kinetic data were obtained in a laminar jet absorber at various contact-times between gas and liquid. The obtained experimental data were interpreted with the aid of a numerically solved absorption-rate/kinetic model. The results showed that only the termolecular mechanism of Crooks and Donnellan could be used to explain all observed kinetic phenomena. These results allowed us to develop a new termolecular-kinetics model for CO2 reaction with MEA solutions, which proved to be better than previously published kinetic models. The model was comprehensive enough to describe for the first time the absorption Of CO2 in highly concentrated and high CO2-loaded aqueous MEA solutions for a wide temperature range. (C) 2003 Elsevier Ltd. All rights reserved.