CO2 removal in tray tower by using AAILs activated MDEA aqueous solution

A tray tower was designed to verify the absorption performance of CO 2 in 1-butyl-3-methylimidazolium glycinate ([Bmim][Gly]), 1-butyl-3-methylimidazolium lysinate ([Bmim][Lys]) and tetramethylammonium glycinate ([N 1111 ][Gly]) activated MDEA ( N -methyldiethanolamine) aqueous solutions. The simulated flue gas was composed of 15% (mole fraction) CO 2 and 85% N 2 and the experiments were performed at 313.2 K. To find a suitable absorbent composition, the mass fractions of MDEA and amino acid ionic liquids (AAILs) respectively ranged from 0.200 to 0.400 and 0.025 to 0.100. The removal efficiency of CO 2 ( η CO 2 ) and the overall volumetric mass transfer coefficient ( K G a v ) were determined. The effects of absorbent composition ( w ), absorbent flow rate ( L ), gas flow rate ( G ) and plate number ( N p ) on η CO 2 and K G a v were demonstrated. Our results showed that, when activated by AAILs, MDEA aqueous solution was able to absorb CO 2 in tray tower efficiently, and both η CO 2 and K G a v were significantly increased, e.g., in the case of w MDEA  = 0.200, η CO 2 and K G a v were increased from 43.48% to 95.55% and from 0.0069 (kmol m −3  h −1 ·kPa −1 ) to 0.0350 (kmol m −3  h −1 ·kPa −1 ), respectively, when w [N1111][Gly] was changed from 0 to 0.100, indicating AAILs activated MDEA aqueous solution is of great potential for industrial application in CO 2 capture process.