ABSTRACT

We have investigated the CO2 absorption properties in 1-ethyl-3-methylimidazolium (Emim) ionic liquids with the anions (TFSA, bis(trifluoromethanesulfonyl)amide; BETA, bis(pentafluoroethanesulfonyl) amide; NFBS, nonafluorobutanesulfonate; BF4, tetrafluoroborate) using a magnetic suspension balance at 313.15 K and pressures up to 6 MPa. To obtain accurate CO2 solubility, the buoyancy correction was made by taking account of the volume expansion of ionic liquids caused by CO2 dissolution. In the present work, Sanchez-Lacombe equation of state was used for such volume corrections at high pressures. As a result, the solubilities of carbon dioxide in [Emim][TFSA] are consistent with the literature data. The solubilities of carbon dioxide in the ionic liquids studied showed typical pressure dependence as physical absorption, and increased in the following order of the anion: BF4 less than NFBS less than TFSA less than BETA.

Compounds

#	Formula	Name
1	CO2	carbon dioxide
2	C8H11F6N3O4S2	1-ethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide
3	C10H11F10N3O4S2	1-ethyl-3-methylimidazolium 1,1,2,2,2-pentafluoro-N-[(pentafluoroethyl)sulfonyl]ethanesulfonamide
4	C10H11F9N2O3S	1-ethyl-3-methyl-1H-imidazol-3-ium 1,1,2,2,3,3,4,4,4-nonafluorobutane-1-sulfonate
5	C6H11BF4N2	1-ethyl-3-methylimidazolium tetrafluoroborate

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	2	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	11
POMD	2	Mass density, kg/m3 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid	Vibrating tube method	7
POMD	3	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	11
POMD	3	Mass density, kg/m3 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid	Vibrating tube method	7
POMD	4	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	8
POMD	4	Mass density, kg/m3 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid	Vibrating tube method	7
POMD	5	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Vibrating tube method	9
POMD	5	Mass density, kg/m3 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid	Vibrating tube method	7
POMD	1 2	Mole fraction - 1 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid Gas	gravimetric	7
POMD	1 3	Mole fraction - 1 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid Gas	gravimetric	7
POMD	1 4	Mole fraction - 1 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid Gas	gravimetric	7
POMD	1 5	Mole fraction - 1 ; Liquid	Pressure, kPa; Liquid	Temperature, K; Liquid	Liquid Gas	gravimetric	7

Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

CO2 absorption properties of imidazolium based ionic liquids using a magnetic suspension balance

Watanabe, M.[Masaki], Kodama, D.[Daisuke], Makino, T.[Takashi], Kanakubo, M.[Mitsuhiro]

ABSTRACT