ABSTRACT

The liquid liquid equilibria of ionic liquid-based systems with water and/or acetic acid have been studied at 293.15 K and atmospheric pressure. One hydrophilic ionic liquid and a series of hydrophobic ionic liquids were investigated in order to examine their effect on the separation of water and acetic acid mixtures. The ionic liquids studied were [P666,14]Cl, [P666,14][NTf2], [C4mmim][NTf2], [Cnmim][NTf2] (n = 2, 4, 6, 8, or 10), [C4mpyrr][NTf2], [N1114][NTf2], and [C2mim][EtSO4]. [C2mim][EtSO4] is totally miscible with water and acetic acid in all compositions. Comparing [P666,14]Cl with [P666,14][NTf2], the former showed higher extraction selectivities; however, due to the larger viscosity of [P666,14]Cl, the [NTf2]- based ionic liquids offer a better solvent choice for the liquid extraction processes. As expected, as the solubility of water decreases with increasing the chain length of ionic liquids, this in turn leads to [C10mim][NTf2] showing greater acetic efficiency than [C2mim][NTf2] for the separation of water and acetic acid. The experimental data obtained for ternary systems containing the [C4mmim][NTf2] demonstrated that the modification of the C(2) position on the imidazolium ring does not significantly affect the selectivity compared with [C4mim][NTf2]. Tetraalkyl ammonium and N-alkyl pyrrolidinium based ionic liquids were also studied with the [NTf2]- anion with the results for the system containing the [C4mpyrr][NTf2] demonstrating a higher selectivity for the separation of water and acetic acid than the other [NTf2]- based systems studied. All experimental data were then correlated using the UNIQUAC model within an accuracy close to 1.6%. Finally, the ionic liquids were also compared with standard molecular extraction solvent, for example, methyl tert-butyl ether and methyl isobutyl ketone. The organic solvents showed an advantage over the [Cnmim][NTf2]-based ionic liquids but only over a narrow composition range. In all ionic liquid systems, the selectivity remains high at low acetic acid concentration compared with that found in the organic solvents, which is important for practical operation and demonstrates the advantages of using an ionic liquid for the extraction.

Compounds

#	Formula	Name
1	H2O	water
2	C2H4O2	acetic acid
3	C5H12O	2-methoxy-2-methylpropane
4	C6H12O	4-methylpentan-2-one
5	C32H68ClP	trihexyl(tetradecyl)phosphonium chloride
6	C34H68F6NO4PS2	trihexyl(tetradecyl)phosphonium bis[(trifluoromethyl)sulfonyl]imide
7	C8H11F6N3O4S2	1-ethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide
8	C10H15F6N3O4S2	1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide
9	C11H17F6N3O4S2	1-butyl-2,3-dimethyl-1H-imidazolium bis(trifluoromethylsulfonyl)amide
10	C12H19F6N3O4S2	1-hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide
11	C14H23F6N3O4S2	1-octyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide
12	C16H27F6N3O4S2	1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide
13	C11H20F6N2O4S2	1-butyl-1-methylpyrrolidinium bis[(trifluoromethyl)sulfonyl]imide
14	C9H18F6N2O4S2	butyltrimethylammonium bis(trifluoromethylsulfonyl)imide

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 3 1	Mole fraction - 3 ; Liquid mixture 1 Mole fraction - 2 ; Liquid mixture 2 Mole fraction - 3 ; Liquid mixture 2	Temperature, K; Liquid mixture 2 Mole fraction - 2; Liquid mixture 1	Pressure, kPa; Liquid mixture 2	Liquid mixture 1 Liquid mixture 2	NMR NMR NMR	18
POMD	2 4 1	Mole fraction - 4 ; Liquid mixture 1 Mole fraction - 2 ; Liquid mixture 2 Mole fraction - 4 ; Liquid mixture 2	Mole fraction - 2; Liquid mixture 1	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2	Liquid mixture 1 Liquid mixture 2	NMR NMR NMR	11
POMD	2 1 5	Mole fraction - 5 ; Liquid mixture 2 Mole fraction - 5 ; Liquid mixture 1 Mole fraction - 2 ; Liquid mixture 1	Mole fraction - 2; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	OTHER OTHER OTHER	22
POMD	2 1 6	Mole fraction - 2 ; Liquid mixture 1 Mole fraction - 6 ; Liquid mixture 2 Mole fraction - 2 ; Liquid mixture 2	Mole fraction - 6; Liquid mixture 1	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2	Liquid mixture 1 Liquid mixture 2	NMR NMR NMR	6
POMD	2 1 7	Mole fraction - 2 ; Liquid mixture 2 Mole fraction - 7 ; Liquid mixture 1 Mole fraction - 2 ; Liquid mixture 1	Mole fraction - 7; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR NMR NMR	10
POMD	2 1 8	Mole fraction - 2 ; Liquid mixture 2 Mole fraction - 8 ; Liquid mixture 1 Mole fraction - 2 ; Liquid mixture 1	Mole fraction - 8; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR NMR NMR	13
POMD	2 1 9	Mole fraction - 2 ; Liquid mixture 1 Mole fraction - 9 ; Liquid mixture 2 Mole fraction - 2 ; Liquid mixture 2	Mole fraction - 9; Liquid mixture 1	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2	Liquid mixture 1 Liquid mixture 2	NMR NMR NMR	10
POMD	2 1 10	Mole fraction - 10 ; Liquid mixture 2 Mole fraction - 2 ; Liquid mixture 1 Mole fraction - 10 ; Liquid mixture 1	Mole fraction - 2; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR NMR NMR	16
POMD	2 1 11	Mole fraction - 11 ; Liquid mixture 2 Mole fraction - 2 ; Liquid mixture 1 Mole fraction - 11 ; Liquid mixture 1	Mole fraction - 2; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR NMR NMR	10
POMD	2 1 12	Mole fraction - 12 ; Liquid mixture 2 Mole fraction - 2 ; Liquid mixture 1 Mole fraction - 12 ; Liquid mixture 1	Mole fraction - 2; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR NMR NMR	9
POMD	2 1 13	Mole fraction - 13 ; Liquid mixture 2 Mole fraction - 2 ; Liquid mixture 1 Mole fraction - 13 ; Liquid mixture 1	Mole fraction - 2; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR NMR NMR	9
POMD	2 1 14	Mole fraction - 14 ; Liquid mixture 2 Mole fraction - 2 ; Liquid mixture 1 Mole fraction - 14 ; Liquid mixture 1	Mole fraction - 2; Liquid mixture 2	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR NMR NMR	10
POMD	3 1	Mole fraction - 3 ; Liquid mixture 2	Temperature, K; Liquid mixture 1	Pressure, kPa; Liquid mixture 1	Liquid mixture 2 Liquid mixture 1	NMR	2
POMD	3 1	Mole fraction - 3 ; Liquid mixture 1	Temperature, K; Liquid mixture 1	Pressure, kPa; Liquid mixture 1	Liquid mixture 1 Liquid mixture 2	NMR	2
POMD	4 1	Mole fraction - 4 ; Liquid mixture 2	Pressure, kPa; Liquid mixture 1 Temperature, K; Liquid mixture 1		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 5	Mole fraction - 5 ; Liquid mixture 1	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	OTHER	1
POMD	1 6	Mole fraction - 6 ; Liquid mixture 2	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 7	Mole fraction - 7 ; Liquid mixture 1	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1
POMD	1 7	Mole fraction - 7 ; Liquid mixture 2	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 8	Mole fraction - 8 ; Liquid mixture 1	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1
POMD	1 8	Mole fraction - 8 ; Liquid mixture 2	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 9	Mole fraction - 9 ; Liquid mixture 1	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1
POMD	1 9	Mole fraction - 9 ; Liquid mixture 2	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 10	Mole fraction - 10 ; Liquid mixture 1	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1
POMD	1 10	Mole fraction - 10 ; Liquid mixture 2	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 11	Mole fraction - 11 ; Liquid mixture 1	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1
POMD	1 11	Mole fraction - 11 ; Liquid mixture 2	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 12	Mole fraction - 12 ; Liquid mixture 1	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1
POMD	1 12	Mole fraction - 12 ; Liquid mixture 2	Temperature, K; Liquid mixture 2 Pressure, kPa; Liquid mixture 2		Liquid mixture 2 Liquid mixture 1	NMR	1
POMD	1 13	Mole fraction - 13 ; Liquid mixture 1	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1
POMD	1 14	Mole fraction - 14 ; Liquid mixture 1	Pressure, kPa; Liquid mixture 2 Temperature, K; Liquid mixture 2		Liquid mixture 1 Liquid mixture 2	NMR	1

Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Liquid-Liquid Equilibria of Ionic Liquids-Water-Acetic Acid Mixtures

Wang, S.[Silu], Liu, J.[Jingyi], Hembre, R.[Robert], Barnicki, S.[Scott], Goodrich, P.[Peter], Hughes, T.-L.[Terri-Louise], Rooney, D. W.[David W.], Sink, C.[Chester], Jacquemin, J.[Johan], Hardacre, C.[Christopher]

ABSTRACT