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 K_Ga_v 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 K_Ga_v model was proposed and developed on basis of the observed experimental value of K_Ga_v, which gave a much better predication performance in comparison with empirical Kohl-Risenfield-Astarita model and Sheng model with respect to AAD.