Characterization and kinetics of CO2 absorption into aqueous 1-ethyl-3-methylimidazolium glutamate solution

Abstract

The kinetic of carbon dioxide (CO2) into aqueous 1-ethyl-3-methylimidazolium glutamate ([Emim]2[Glu]) solution was investigated by a double stirred-cell absorber. The Density and viscosity of [Emim]2[Glu] solution were measured with concentrations ranging from 0.3 to 1.5molL−1 at temperatures from 298.15 to 323.15K. The diffusivity of CO2 in [Emim]2[Glu] solution were estimated at the same temperatures and concentrations. The effects of the [Emim]2[Glu] concentration, absorption temperature and CO2 concentration were studied. The results showed that absorption CO2 into aqueous [Emim]2[Glu] solution was the fast pseudo-first order reaction regime. The enhancement factor E, the overall reaction kinetic constant kOV and the second-order rate constant k2 were calculated by the two-film theory. The result showed that E was linear with CILs1/2, and the second-order rate constant could be expressed as following equation: k2=9.253×107exp(−3665/T).