CO2 capture performance of AMP-EAE amine blends: Absorption in the microchannel and desorption from saturated solutions

Abstract

Blended organic amine solutions are considered an effective strategy for developing highly efficient and low energy-consuming absorbents due to the possibility of combining the advantages of single amine. The 2-amino-2-methyl-1-propanol (AMP) and 2-(ethylamino)ethanol (EAE) amine blends were prepared in three molar ratios: blend-1 (n_AMP:n_EAE = 3:1), blend-2 (n_AMP:n_EAE = 1:1), and blend-3 (n_AMP:n_EAE = 1:3). The impacts of gas-liquid flow rate, amine concentration, molar ratio, temperature, and CO₂ concentration on absorption performance were investigated using the serpentine microchannel. Additionally, the effects of amine concentration and molar ratio on the desorption performance of saturated solutions were also explored. The performance of amine blends in absorption and desorption was evaluated by measuring absorption rate, efficiency, and loading, as well as desorption efficiency, energy consumption, cycle capacity, and average desorption rate. The desorption results were compared to those of the benchmark solvent, 30 wt% MEA, under identical operating conditions. The results indicate that the 25 wt% blend-2 solution performs exceptionally well, exhibiting a 15 % increase in absorption efficiency compared to the AMP aqueous solution at a gas-liquid ratio of 20. Additionally, the cycle capacity and average desorption rate are 1.7 times higher than those of the 30 wt% MEA solution. Notably, the energy consumption of the 25 wt% blend-2 solution for desorption is only 60 % of the 30 wt% MEA solution.