Comparison of mass transfer coefficients and desorption rates of CO2 absorption into aqueous MEA plus ionic liquids solution

The mixed solvent of ionic liquids and ethanolamine (MEA) was used to absorb CO2 from mixed gases using a packed column. The density and viscosity of aqueous MEA + ionic liquids solution were determined at temperatures ranging from 303.15 to 323.15 K and ionic liquids mass concentrations from 20% to 30%, respectively. A comparison among the mass transfer of CO2 absorption into MEA + ionic liquids ([Bmim][Br], [Emim][Br]) and MEA was performed at 303.15-323.15 K. Meanwhile, the effects of the temperature, liquid flow rate and gas flow rate on the K(G)a(v) value were discussed in this paper, respectively. At last, the desorption rates of rich solution were calculated by determining the volume of CO2 released from rich solution. The result showed that aqueous MEA + 20% [Emim] [Br] solution had superior performance for CO2 capture. Moreover, as CO2 was absorbed by the mixture of MEA and ionic liquids, the catalytic action of ionic liquids was not obvious. (C) 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.