CO 2 absorption into aqueous solutions of N‐methyl‐1,3‐propane‐diamine and its blends with N,N‐diethylethanolamine—New kinetic data

Summary The rates of CO 2 absorption into aqueous solutions of N‐methyl‐1,3‐propane‐diamine (MAPA) and its mixture with N,N‐diethylethanolamine (DEEA) have been studied in a stirred cell reactor under the fast reaction regime. The experiments were carried out for 0.2 M MAPA and DEEA + MAPA blends with a total amine concentration of 2 M over the temperature range of 303 to 333 K. It was found that relatively low concentrations of MAPA ranging from 0.05 to 0.2 M in DEEA solutions significantly accelerated the rate of CO 2 absorption. Kinetic data for the reactions of CO 2 with MAPA were not available in the literature within the present experimental range. Based on the experiments in DEEA+MAPA blends, the pseudo‐first‐order rate constants were calculated and analyzed together in one global analysis. Using the termolecular mechanism, the specific kinetic rate constants for the reactions between CO 2 and MAPA were determined and correlated by the Arrhenius equation. Finally, a comparison of the efficiency of the studied MAPA with other fast amines including N‐ethylethanolamine, 1,6‐hexamethyldiamine, N‐[2‐aminoethyl] ethanolamine), and piperazine confirmed its potential as an excellent rate promoter for CO 2 absorption.