Kinetics of CO2 absorption by aqueous mixtures of N,N′‐diethylethanolamine and polyamines

Abstract Aqueous solutions of N , N ʹ‐diethylethanolamine (DEEA) are prospective high‐capacity CO 2 ‐capturing solvents. Their reactivity can be enhanced by promotion with absorption activators. Two polyamines were chosen as activators in this work, viz. (methylamino)propylamine (MAPA) and diethylene triamine (DETA). In a stirred cell reactor, kinetics of CO 2 absorption into aqueous DEEA/MAPA and DEEA/DETA mixtures was studied at 303 K. The molarity of DEEA was varied in the 2–2.5 M range, whereas the polyamine concentration was changed between 0.1 and 0.5 M. Pseudo–first‐order rate constants were reported. Second‐order rate constants for the CO 2 reactions with MAPA and DETA were determined too. DETA reacts faster than MAPA.