Mass transfer performance of CO2 absorption into aqueous DEEA in packed columns

A bench-scale absorption column packed with high efficiency Sulzer DX-type packing was used to determine the volumetric overall mass transfer coefficient (KGav) for CO2 absorption into an aqueous solution of DEEA. The effects of the main operating parameters, such as liquid feed temperature, DEEA concentration, lean CO2 loading, liquid flow rate, CO2 partial pressure, and inert gas flow rate were examined. The results showed that DEEA concentration, CO2 lean loading, and liquid flow rate had a significant effect on KGav while inert gas flow rate had little effect. In addition, CO2-loaded aqueous DEEA solution was observed to have a higher KGav as compared to that of aqueous MDEA solutions. Also, the performance of CO2 absorption with DEEA in structured packing in terms of KGav and cyclic capacity (Δα) were compared with the performance in a random packing column. The structured packing column performed better than the random packing column. Finally, two experimental KGav correlation models for CO2-DEEA system were proposed and found to be in satisfactory agreement with experimental results with AAD of 8 and 3%, respectively.