Kinetics of reactive absorption of CO2 using aqueous blend of potassium carbonate, ethylaminoethanol, and N-methyl-2-Pyrollidone (APCEN solvent)

Abstract

Employing the fall in the CO2 pressure method, the kinetics of the reactive absorption of CO2 in the aqueous blend of potassium carbonate, ethylaminoethanol, and N-methyl-2-Pyrollidone (APCEN solvent) is inspected by altering the amine concentration and the absorption temperature. The rate of the absorption of CO2 and the solubility/diffusivity of CO2 in the APCEN solvent is ascertained by using a stirred cell reactor. Based on the obtained experimental findings, the order of the absorption for CO2 in the APCEN solvent is estimated and understood to be of overall second order (1st order with respect to both EAE and CO2, respectively). The rate of the absorption of CO2 in the APCEN solvent is observed to be noticeably higher than the APCE solvent (aqueous potassium carbonate promoted by ethylaminoethanol) and numerous other secondary amines. For instance, at 303 K (with EAE concentration equal to 1.5 kmol m?3), the rate of the absorption of CO2 in the APCEN solvent is 18.8% higher than the APCE solvent. By studying the effect of the absorption temperature, the activation energy for the APCEN solvent is determined and viewed to be equivalent to the APCE solvent. Furthermore, the lumped parameter in case of the APCEN solvent is higher (1.41 ? 10? 6 kmol1/ 2 m?1/ 2 s? 1 kPa?1) as compared to the APCE solvent (1.2 ? 10? 6 kmol1/ 2 m?1/ 2 s? 1 kPa?1). In total, the rate of absorption of CO2 in the APCEN solvent is considerably higher than that of the APCE solvent, and other secondary amines such as methylmonoethanolamine (MMEA), propylmonoethanolamine (PMEA), and butylmonoethanolamine (BMEA). ? 2018 Taiwan Institute of Chemical Engineers