A Study on CO 2 Absorption Kinetics by Aqueous Solutions of N , N ‐Diethylethanolamine and N ‐Ethylethanolamine

N ‐Ethylethanolamine (EEA) and N , N ‐diethylethanolamine (DEEA) represent promising candidate alkanolamines for CO 2 removal from gaseous streams, as they can be prepared from renewable resources. In this work, the reaction rate constant for the reaction between CO 2 and EEA was determined from the absorption rate measurements of CO 2 in a blend comprising DEEA, EEA and H 2 O. A stirred‐cell reactor with a plane, horizontal gas‐liquid interface was used for the absorption studies. While the DEEA concentration in the formulated solution was varied in the range of 1.5–2.5 kmol/m 3 , the initial EEA concentration was 0.1 kmol/m 3 . A zwitterion mechanism for EEA and a base‐catalyzed hydration mechanism for DEEA were used to describe the reaction kinetics. At 303 K, the second‐order reaction rate constant for the CO 2 reaction with EEA was found to be 8041 m 3 /(kmol s). The liquid‐side mass transfer coefficient was also estimated, and its value (0.004 cm/s) is in line with those typical of stirred‐cell reactors.