Kinetics of CO2 absorption into aqueous 1-ethyl-3-methylimidazolium glycinate solution

Abstract

The kinetic of CO2 absorption into aqueous 1-ethyl-3-methylimidazolium glycinate ([C2mim][Gly]) solution was investigated using a double stirred-cell absorber. Density and viscosity of the [C2mim][Gly]) solution were determined, then diffusion coefficient DCO2 and solubility of CO2 were estimated. The effects of [C2mim][Gly] concentration, absorption temperature and CO2 concentration in bulk gas were studied. Calculated results proved that CO2 absorption into aqueous [C2mim][Gly] solution was carried out according to a fast pseudo-first order reaction regime. Hatta number (Ha), the enhancement factor (E), the overall reaction rate constant (kOV) and the second-order rate constant (k2) were calculated by gas–liquid two-film theory. The result showed that E was linear with CILs1/2, and the second-order rate constant was expressed as following equation: k2=6.041×106exp-2801T.