Solubility of CO₂ in Water + Diethanolamine + 2-Amino-2-methyl-1-propanol

This work presents new experimental results for the CO 2 solubility in aqueous blends of diethanolamine (DEA) + 2-amino-2-methyl-1-propanol (AMP) in the temperature range of (303 to 323) K and CO 2 partial pressure of (1 to 100) kPa. The mass fractions of the aqueous amine blends were 1.5 % DEA + 28.5 % AMP, 3 % DEA + 27 % AMP, 4.5 % DEA + 25.5 % AMP, and 6 % DEA + 24 % AMP. A rigorous thermodynamic model is developed to correlate and predict the vapor−liquid equilibrium (VLE) of CO 2 in aqueous blends of DEA and AMP. The modified Clegg−Pitzer equations have been used to develop a model for the quaternary system (CO 2 + AMP + DEA + H 2 O) using the interaction parameters derived from the VLE data of the corresponding ternary systems (CO 2 + AMP + H 2 O) and (CO 2 + DEA + H 2 O). Simulated annealing has been used for parameter estimation and for the determination of equilibrium composition of various species present in the liquid phase. The model predictions are in good agreement with the experimental data of CO 2 solubility in DEA + AMP blends of this work as well as those reported in the literature.