Hybrid behaviors of CO2 absorption into blended DEEA‐based solution for the improvement of capture performance

Abstract

AbstractBACKGROUNDAt present, the chemical absorption method of CO2 capture is considered to be an effective means to reduce carbon emissions. The development of blended amine systems with excellent CO2 capture performance is the focus of research.RESULTThe hybrid behaviors of N,N‐diethylethanolamine (DEEA) with addition of monoethanolamine (MEA), 2‐(methylamino)ethanol(MAE) and 2‐((2‐aminoethyl)amino)‐ethanol(AEEA) as absorbents were investigated and developed to reduce the energy consumption for solvent regeneration in the CO2 capture process. The equilibrium solubility of CO2 for blended DEEA/MEA, DEEA/MAE and DEEA/AEEA with a series of molar ratios (0.0:2.0, 0.5:1.5, 1.0:1.0, 1.5:0.5 and 2.0:0.0) was examined. The experimental results showed that the values of CO2 equilibrium solubility of amine blends exhibited a compromise behavior between each individual amine solution. Additionally, the effects of molar ratios on the relative CO2 absorption rate, regeneration rate and CO2 cyclic capacity for the tested amine blends were studied using an improved rapid absorbent screening method.CONCLUSIONThe experimental data showed that the blended DEEA/MAE solution exhibits much higher CO2 cyclic capacity than that of DEEA/AEEA under the nitrogen atomic conservation. However, the mixing DEEA and AEEA could obviously reduce the CO2 equilibrium solubility and CO2 cyclic capacity compared with that of individual AEEA solution, indicating the DEEA had an inhibiting effect on AEEA. Furthermore, the mass transfer performances of DEEA, DEEA/MAE and DEEA/AEEA were tested in order to validate the accuracy of the improved rapid absorbent screening method. © 2024 Society of Chemical Industry (SCI).