A new reactive absorption model using extents of reaction and activities. II. Application to CO2 absorption into aqueous MDEA solutions

•A new general steady-state and activity-based absorption model is proposed.•The number of differential equations in the reactive absorption problem is reduced by using extents of reactions.•Coherent literature CO2 absorption/desorption flux datasets in aq. MDEA solution are selected.•An activity-based rate constant for CO2 reaction with MDEA is derived, with 18% overall AAD.•The contributions of MDEA and HO– ion to CO2 absorption in non ideal solutions are characterized.