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

• Published in: Chemical engineering science 2012-10, Vol.81, p.251-259
• Main Authors: Sema, Teerawat, Naami, Abdulaziz, Liang, Zhiwu, Idem, Raphael, Tontiwachwuthikul, Paitoon, Shi, Huancong, Wattanaphan, Pathamaporn, Henni, Amr
• Format: Article
• Language: English
• Subjects: Absorption; Absorption, stripping; Amine Bronsted plot; Applied sciences; Carbon dioxide; Chemical engineering; Chemical reactions; Exact sciences and technology; Heat and mass transfer. Packings, plates; Kinetics; Mass transfer; Mathematical models; Rate constants; Reaction kinetics; Reaction rate constant; Reactors; Solvents
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2012.06.028

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,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,DEAB can also be simply predicted using a predictive correlation developed based on the Brφnsted 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,DEAB based on the Brφnsted plot was developed. ► DEAB was found to be a potentially alternative solvent for capturing CO2.