| Abstract |
In a circular economy and sustainability context, CO2 utilization is key. For photochemical or electrochemical transformations, CO2 absorption in liquids has become crucial and even a limiting step. This work aimed to establish an average mass transport coefficient (kLa) characteristic of the CO2 absorption in water and in alkaline solutions in capillary absorbers (2-4 mm) under Taylor flow and recirculation mode. A correlation among prevailing dimensionless numbers (Sh, Re, Ca and Sc) was also established. To achieve so, the absorption of CO2 was conducted in both, water and NaOH solutions (0.5 mol/dm3), and its concentration was monitored by measuring total inorganic carbon and pH. The gas and liquid flowrates used for the tests were 1.66x10-4 L/s and 2.5x10-4 L/s, respectively. The effect of temperature was investigated in the range of 283 and 308 K. The highest kLa was found to be 12 x 10-2 and 2.1 x 10-2 s1, for water and NaOH solutions, respectively. The modelling and simulation of the carbon species formation and production was also conducted and a determination coefficient (R2) of 0.99 was found. (c) 2023 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved. |
