Heat of absorption of CO2 in aqueous N,N-diethylethanolamine?+?N-methyl-1,3-propanediamine solutions at 313?K

Differential heat of absorption of CO_2 in aqueous solutions of N,N-diethylethanolamine(DEEA) and activated DEEA solutions up to a total concentration of 2 mol·L~(-1) was measured as a function of CO_2 loading at 313.15 K using a reaction calorimeter. In order to analyze the performance of N-methyl-1,3-propanediamine(MAPA)as an activator, DEEA blended solutions containing 0.05, 0.1 and 0.2 mol·L~(-1) MAPA were studied. The heat of CO_2 absorption in single DEEA solutions was unaffected by changing the DEEA concentration in the range of(0.5–2) mol·L~(-1). On the other hand, increasing the concentration of MAPA in aqueous amine mixtures of(DEEA + MAPA) raised the heat of absorption.