Experiments and Modeling of Vapor-liquid Equilibrium in DEEA-CO2-H2O System

Abstract New vapor-liquid equilibrium (VLE) experimental data has been collected for DEEA in the concentration range of 1 to 4 M at temperatures of 293K, 313K, 333K, and 353K for CO 2 partial pressure in the range from 6.2kPa-100.8 kPa. An empirical model has been established based on the experimental data. A comparison of experimental and predicted data gave absolute average deviation of 1.72%, 2.68%, 1.32%, and 10.32% for DEEA concentration of 1 M, 2 M, 3 M, and 4 M respectively. The Kent-Eisenberg (KE) model was chosen to predict vapor-liquid equilibrium for the DEEA-CO 2 -H 2 O system. Both the Henry's constant for N 2 O in aqueous DEEA and the equilibrium constant (K 10 ) for the dissociation of protonated amine were regressed. The absolute average deviations (AAD) for ln(K 10 ) for 1 M, 2 M, 3 M, and 4 M DEEA solution were 0.62%, 1.18%, 1.40% and 1.65% respectively, indicating excellent agreement. From these results, the KE model is well suited when DEEA concentration and temperature are low. The predictions in 1 M and 2 M are acceptable with the absolute average deviations of 3.28% and 5.10% respectively.