Analysis of reaction kinetics of CO2 absorption into a novel reactive 4-diethylamino-2-butanol solvent

In the present work, a comprehensive numerically solved reaction rate/kinetics model that takes into account the coupling between chemical equilibrium, mass transfer, and chemical kinetics of all possible chemical reactions for CO2 absorption into aqueous 4-diethylamino-2-butanol (DEAB) was successfully developed. The second order reaction rate constant of DEAB (k2,DEABk2,DEAB) was extracted from the model and can be expressed and ranked as: k2,DEAB=(4.01×1013)exp(−7527.7T) and PZ»MEA»DEAB∼AMP∼DEA>MDEA, respectively. The predicted CO2 absorption rates obtained from the developed reaction rate/kinetics model fit favourably with the experimental results with an AAD of 6.5%. In addition, k2,DEABk2,DEAB can also be simply predicted using a predictive correlation developed based on the Brφφnsted plot with an AAD of 7.6%.

► Kinetics in DEAB–CO2–H2O was studied using laminar jet absorber.
► Reaction kinetics data were interpreted using 1D numerically solved model.
► Reaction kinetics can be ranked as: PZ»MEA»DEAB∼AMP∼DEA>MDEA.
► Predictive correlation of k2,DEABk2,DEAB based on the Brφφnsted plot was developed.
► DEAB was found to be a potentially alternative solvent for capturing CO2.