The vapor liquid equilibrium test bench was set up

and the data of vapor liquid equilibrium of CO2 in aqueous mixture of 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim] [BF4]) and monoethanolamine (MEA) were measured. The desorption energy consumption of this absorbent was calculated. The results showed that with the increase of temperature

the corresponding CO2partial pressure of the solution increased

and the change of the mass fraction of[Bmim] [BF4] had little influence on the vapor liquid equilibrium. Compared with 30% MEA

the main advantage of this absorbent in terms of energy consumption lies in the reduction of sensible heat and latent heat during desorption. The reaction heat decreased significantly after the CO2 loading was greater than 0.45

and the decrease of latent heat was mainly due to the decrease of the partial pressure and mole fraction of H2O in gas phase in the desorption tower. When the mass fraction of[Bmim] [BF4] was bigger than 30%

the energy consumption of sensible heat could be decreased by more than 30%

and the main reasons for the decrease were the decrease of specific heat capacity and the increase of amine concentration in rich phase liquid.