Kinetics of CO₂ Absorption in an Ethylethanolamine Based Solution

The kinetics of CO₂ absorption in ethylethanolamine based solutions were investigated using a wetted wall column (WWC) from 298 to 328 K. In the nonaqueous solutions, monoethylethanolamine (EMEA) was the reactant with a concentration range from 0.5 to 3.0 kmol m^-3, and diethylethanolamine (DEEA) was the solvent. Water with volume ratio range from 0 to 150 % was added into 3.0 kmol m^-3 EMEA + DEEA solution forming hydrated solutions. The overall reaction rate constants were obtained from the CO₂ flux under the condition of a pseudo-first-order and fast reaction regime. The reaction rate of CO₂ with nonaqueous solutions increased with either EMEA concentration or temperature, which can be represented by the termolecular mechanism. The reaction rate of CO₂ with hydrated solutions increased with water volume ratio, which can be represented by both the zwitterion and the termolecular mechanisms.