The analysis of solubility, absorption kinetics of CO₂ absorption into aqueous 1-diethylamino-2-propanol solution

In this present work, the CO₂ absorption performance of aqueous 1-diethylamino-2-propanol (1DEA2P) solution was studied with respect to CO₂ equilibrium solubility, absorption kinetics, and absorption heat. The equilibrium solubility of CO₂ in 2M 1DEA2P solution was measured over the temperature range from 298 to 333 K and CO₂ partial pressure range from 8 to101 kPa. The absorption kinetics data were developed and analyzed using the base-catalyzed hydration mechanism and artificial neural network models (radial basis function neural network [RBFNN] and back-propagation neural network [BPNN] models) with an acceptable absolute average deviation of 10% for base-catalyzed hydration mechanism, 2.6% for RBFNN model and 1.77% for BPNN model, respectively. The CO₂ absorption heat of 1DEA2P was estimated to be −43.6 kJ/mol. In addition, the ions (1DEA2P, 1DEA2PH⁺, HCO^-₃, CO^2-₃) speciation plots of the 1DEA2P-CO₂-H₂O system were developed to further understand the reaction process of 1DEA2P with CO₂. Based on a comparison with conventional amines (e.g., MEA, DEA, MDEA) and alternative amines (i.e., 1DMA2P and 4-(diethylamino)−2-butanol [DEAB]), 1DEA2P exhibited good performance with respect to CO₂ equilibrium solubility, reaction kinetics, and CO₂ absorption heat. Meanwhile, the overall evaluation of 1DEA2P for application in CCS in terms of absorption and desorption is presented, giving helpful information for the screening of these novel amines.