Carbon dioxide absorption kinetics in potassium threonate

Abstract

The absorption of carbon dioxide in potassium threonate aqueous solutions is studied at concentrations ranging from 0.1 to 3 M and temperatures from 293 to 313 K. This study includes experimental density, viscosity, solubility of N 2O and absorption kinetics of CO 2 (using a stirred cell reactor) data obtained for the various potassium threonate solutions. The diffusion coefficients of CO 2 and potassium threonate in the absorption solutions are estimated using a modified Stokes–Einstein relation. N 2O solubility is interpreted using the Schumpe [1993. The estimation of gas solubilities in salt-solutions. Chemical Engineering Science 48(1), 153–158] model and CO 2 physical solubility estimated. Physical absorption experiments were performed in the stirred cell in order to determine the physical mass transfer coefficients. The kinetics results are interpreted using both the pseudo-first-order and the DeCoursey approaches. It was concluded that CO 2 absorption in the aqueous potassium threonate solutions is well represented by - r CO 2 = 4.13 × 10 8 exp - 3580 T C S exp ( 0.90 C S ) C CO 2