Absorption heat, solubility, absorption and desorption rates, cyclic capacity, heat duty, and absorption kinetic modeling of AMP-DETA blend for post-combustion CO2 capture

This study investigated the absorption heat, equilibrium CO2 solubility, absorption and desorption rates, cyclic capacities, heat duty, and absorption kinetic modeling of amine blends containing AMP and DETA. The AMP and DETA concentrations were varied (1-2.5 kmol/m3 and 0.5-2 kmol/m3, respectively) while the total amine concentration was constant at 3 kmol/m3. The absorption experiment was conducted at 15 %v/v CO2 and 313 K while the desorption temperature was at 363 K. Experimental results revealed that the absorption rates, cyclic capacities and desorption rates of some AMP-DETA blends were higher than those of 5 kmol/m3 MEA. The absorption heat of the blends is comparable to that of MEA while the heat duty of some AMP-DETA blends are much lower than that of 5 kmol/m3 MEA. The optimal amine blend was confirmed to be 2 kmol/m3 AMP - 1 kmol/m3 DETA. A model similar to the power law kinetic model showed that CO2 composition in the feed gas affected the initial absorption rates as compared to AMP/DETA molar concentration ratio. The model predicted the initial absorption rate with a %AAD of 0.52%. These results provide good prospects for AMP-DETA blends towards CO2 capture.