Kinetics of CO2 Capture by Blended MEA-AMP

Carbon dioxide (CO₂) is the largest contributor among greenhouse gases (GHGs) in terms of emissions. Capturing CO₂ from industrial gas stream by aqueous alkanolamine solution is the most cost-effective technology available today. Monoethanolamine (MEA) has been commonly used in gas processing industry for decades. In recent years, a sterically hindered amine, 2-amino-2-methyl-1-propanol (AMP), has gained its popularity since it offers a higher absorption capacity and a lower energy consumption during regeneration compared to MEA. Blending MEA with AMP is predicted to combine all favorable characteristics of both solvents and overcome the unfavorable characteristics. To date, the feasibility of using this blended MEA-AMP has been investigated through fundamental studies, especially in the area of thermodynamics. This work focuses on another fundamental aspect, i.e. kinetics of aqueous MEA-AMP. The kinetic measurements were carried out in a wetted wall column under ranges of process conditions. The column made from a 100 mm-long stainless steel tubing was fitted inside a glass chamber where the temperature of absorption was precisely controlled. The reaction kinetics was interpreted in terms of overall rate constant. Results show that reaction kinetics of MEA-AMP vary with process parameters including mixing ratio of MEA and AMP and absorption temperature.