Absorbent characterization for CO2 capture using wetted-wall column and reaction calorimetry

The absorption characteristics of chemical solvents for CO2 capture have been investigated using a wetted-wall column and reaction calorimetry. The overall mass transfer coefficient (KG) and reaction heat (ΔHR) of subject solvents have been measured. Aqueous solution of monoethanolamine (MEA), 2-amino-2-methyl-1-propanol (AMP), and KIER-C3, a newly proposed chemical, have been used for the study. It was found that KG value of MEA exhibited the highest among the test solvents. The order of KG values with different absorbent solution was found to be ∼10−10 kmol/m2⋅s⋅Pa or higher. The reaction heats of solvents were obtained from the measurement of heat associated with the absorption reaction between the solution and absorbed CO2 molecules. The observed value of reaction heat of MEA was ∼80 kJ/mol at lower loading or less than 0.5 mol CO2/mol-MEA. It is noted that the other criteria such as the absorption capacity, corrosiveness, thermal degradation properties, etc. together with absorption characteristics should be further investigated for the development of absorbent chemical.