Chemical Engineering Journal, Vol.204, 235-243, 2012
Characterization and absorption of carbon dioxide into aqueous solution of amino acid ionic liquid [N-1111][Gly] and 2-amino-2-methyl-1-propanol
Amino acid ionic liquid tetramethylammonium glycinate ([N-1111][Gly]) was mixed with 2-amino-2-methyl-1-propanol (AMP) aqueous solution to form a new solvent for CO2 capture. The density, viscosity and pH of 0-0.40 mol L-1 ([N-1111][Gly]) + 0.95 mol L-1 AMP aqueous solution were investigated at a temperature range of 298-323 K. Solubility and diffusivity of CO2 in ([N-1111][Gly]) + AMP solutions at the same temperatures and concentrations was estimated. The reaction kinetics of CO2 absorption into ([N-1111][Gly]) + AMP aqueous solution was investigated using a double stirred-cell absorber with a planar gas-liquid interface. The results indicated that ([N-1111][Gly]) promoted the absorption of CO2 in 0.95 mol L-1 AMP aqueous solutions. The kinetics region of absorption CO2 into aqueous ([N-1111][Gly]) + AMP solution was the fast pseudo-first order reaction regime. Moreover, the enhancement factor E was linear with C-B0(1/2) and Delta E linear with the concentration of ([N-1111][Gly]) in the mixed aqueous solution, and the activation energy of ([N-1111][Gly]) + AMP aqueous solution absorbing CO2 was 40.7 kJ mol(-1). (C) 2012 Elsevier B.V. All rights reserved.
Keywords:Carbon dioxide;Absorption Kinetics;Tetramethylammonium glycinate;2-Amino-2-methyl-1-propanol