Absorption of CO2 into aqueous blends of alkanolamines prepared from renewable resources

N-ethylethanolamine (EEA) and N,N-diethylethanolamine (DEEA) are potentially attractive chemical solvents for gas purification, as they can be prepared from renewable resources. In this work, the kinetics of the reaction of CO2 with aqueous formulated solutions containing EEA and DEEA was studied in a stirred cell reactor with a plane, horizontal gas-liquid interface, in the range of temperatures 298-308 K. The DEEA concentration in the formulated solution was varied in the range 1.5-2.5 kmol/m(3). EEA was found to act as an effective activator in aqueous DEEA solution. The overall reaction of CO2 with aqueous blends of DEEA and EEA could be regarded as a reaction between CO2 and DEEA in parallel with the reaction of CO2 with EEA. A combined parameter, consisting of the reaction rate constant and the diffusivity and solubility of CO2 in solution, was evaluated. (C) 2007 Elsevier Ltd. All rights reserved.