ABSTRACT

The diffusivity of carbon dioxide and hydrogen sulfide was studied in five ionic liquids containing two different cations and four anions, namely, 1-ethyl-3-methylimidazolium (emim) based ionic liquids with bis-(trifluoromethyl)sulfonylimide (NTf2) anion and 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate, (eFPT) as well as 1-(2-hydroxyethyl)-3-methylimidazolium (hemim) based ionic liquids (ILs) with different anions, viz. hexafluorophosphate (PF6), trifluoromethanesulfonate (OTf) and bis-(trifluoromethyl)sulfonylimide (NTf2). Experimental trials were carried out at temperatures of 303.15, 313.15 and 323.15 K and low initial pressures by means of semi-infinite volume method. The results show that the diffusion coefficients of CO2 and H2S in RTILs increase with increasing temperature, but with different orders, and the diffusivity of CO2 and H2S in (emim) based ILs is greater than that in (hemim) based ILs. In addition, the measured diffusion coefficients of CO2 and H2S have been fitted through Wilke-Chang empirical equation.

Compounds

#	Formula	Name
1	H2S	hydrogen sulfide
2	CO2	carbon dioxide
3	C12H11F18N2P	1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate
4	C8H11F6N3O4S2	1-ethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide
5	C8H11F6N3O5S2	1-(2-hydroxyethyl)-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide
6	C6H11F6N2OP	3-(2-hydroxyethyl)-1-methylimidazolium hexafluorophosphate
7	C7H11F3N2O4S	3-(2-hydroxyethyl)-1-methylimidazolium 1,1,1-trifluoromethanesulfonate

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 4	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 2; Liquid	Liquid	Gas absorption technique	5
POMD	2 3	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 2; Liquid	Liquid	Gas absorption technique	3
POMD	2 5	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 2; Liquid	Liquid	Gas absorption technique	3
POMD	2 6	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 2; Liquid	Liquid	Gas absorption technique	3
POMD	1 4	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 1; Liquid	Liquid	Gas absorption technique	3
POMD	1 3	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 1; Liquid	Liquid	Gas absorption technique	3
POMD	1 5	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 1; Liquid	Liquid	Gas absorption technique	3
POMD	1 6	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 1; Liquid	Liquid	Gas absorption technique	3
POMD	1 7	Binary diffusion coefficient, m2/s ; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Mole fraction - 1; Liquid	Liquid	Gas absorption technique	3

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Experimental diffusion coefficients of CO2 and H2S in some ionic liquids using semi-infinite volume method

Shokouhi, Mohammad, Sakhaeinia, Hossein, Jalili, Amir Hossein, Zoghi, Ali Taghi, Mehdizadeh, Ali

ABSTRACT