A study of kinetics, equilibrium solubility, speciation and thermodynamics of CO2 absorption into benzylamine (BZA) solution

Abstract

The kinetics between BZA and CO2 were investigated by the stopped-flow apparatus over the BZA concentration range from 0.05 to 0.1 mol/L (0.54–1.07 mass%), and over the temperature range from 293 to 313 K. The results also show that the predicted CO2 absorption rate exhibits good agreement with the experimental data with an absolute average deviation (AAD) of 5.15% and 4.15% with respect to the zwitterion and termolecular models, respectively. Furthermore, the NMR experiments confirmed the formation of carbamates. The VLE plots were made with speciation data obtained from NMR techniques applied to the CO2-BZA-H2O system with CO2 loading of 0–0.67 mol CO2/mol BZA at 298 K. A new VLE model was proposed, and the predicted results exhibit good agreement with the experimentaly measured results.