An Experimental Study On Absorption Kinetics Of CO₂ In Aqueous Solution Of MDEA And Sulfolane

For the study on kinetics and thermodynamics of acid gas absorption with an aqueous solution of a chemical absorbent together with a physical absorbent, a vapor-liquid equilibrium measurement method was selected for the experiment. Based on the previous research work, a set of equipment was established for the measurement of gas solubility and absorption rates at low and middle pressures. The explicit characters of the equipment are its simplicity, feasibility and ease of data treatment.In this paper, solubility of carbon dioxide in the mixed-solvent aqueous solution of MDEA and sulfolane at 25.0℃ and 40.0℃ was measured. Kinetic data for the absorption of carbon dioxide with the mixed-solvent solution were also measured at different concentrations of sulfolane and at different stirring rate respectively.The results indicate that the apparent absorption reaction constant decreases with the increased concentration of sulfolane when the concentration of MDEA is fixed. The main reason is the decrease of the diffusion coefficient due to the increase of the solution viscosity. The results also indicate that the apparent absorption reaction constant reach a maximum at the stirring rate of 135 r/min.Finally, a summary and discussion about the improvement of the measurement is also given.