The kinetics absorption Of CO2 into aqueous blends of 2-(1-piperazinyl)-ethylamine (PZEA) and N-methyldiethanolamine (MDEA) were studied at 303, 313, and 323 K using a wetted wall column absorber. The PZEA concentrations in the blends with MDEA varied from 0 to 0.3 kmol m(-3) to see the effect of PZEA as an activator in the blends with two different total amine concentrations (1.0 and 2.0 kmol m(-3)). Based on the pseudo-first-order condition for the CO2 absorption, the overall second-order reaction rate constants were determined from the kinetic measurements. The kinetic rate parameters were calculated and presented at each experimental condition. (c) 2008 Elsevier Ltd. All rights reserved.