Mass transfer mechanism and model of CO2 absorption into a promising DEEA-HMDA solvent in a packed column

Mass transfer performance plays an important role in solvent evaluation as well as design and scale-up of CO2 absorption process. The mass transfer process of CO2 absorption into blended DEEA -HMDA solution was studied over different operating conditions in a lab-scale absorption column packed with Sulzer DX structured packing. The effect of those operating parameters on KGav was fully investigated and discussed in this work. Meanwhile, mass transfer mechanism of CO2 absorption into blended DEEA-HMDA solution was comprehensively presented by identifying the rate-controlling step of mass transfer and the reaction zone of CO2 with amines, which could provide the operation guideline for running plans. In addition, a new KGav model was proposed and developed on basis of the observed experimental value of KGav, which gave a much better predication performance in comparison with empirical Kohl-Risenfield-Astarita model and Sheng model with respect to AAD.