ABSTRACT

This work presents a solubility isothermal titration calorimetry (solITC), a new calorimetric method that allows the determination of solubility product (Ksp) and heat of solution (.Delta.solHo) of hydrophobic ionic compound in water. Based on a single titration of dilute ionic solution into its counterionic solution the method consists of observing the abrupt change of the heat flow signal due to hydrophobic phase separation and fitting the integrated heats to exact thermodynamic model. A priori analysis shows that the applicability range spans for Ksp determination over five orders of magnitudes (typically 10^-9 less than Ksp less than 10^-4 for .Delta.solHo around 30 kJ/mol) keeping at least 5% precision in both Ksp and .Delta.solHo values. For Ksp less than 10^-10, only .Delta.solHo can be precisely determined. The method performance was validated on forming three different types of precipitate with different levels of solubility and heat of solution at T = 298.15 K. The new method is applied to explore 18 cation anion combinations for possible ionic liquid formation.

Compounds

#	Formula	Name
1	C15H30F6N2O4S2	tributylmethylammonium bis((trifluoromethyl)sulfonyl)imide
2	C19H30F18NP	tributylmethylammonium tris(pentafluoroethyl)trifluorophosphate
3	C14H15F18N2P	1-butyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate
4	C16H15F20N3O2P2	1-butyl-3-methylimidazolium bis(bis(perfluoroethyl)phosphoryl)imide
5	C14H15F13N2O3S	1-butyl-3-methylimidazolium perfluorohexylsulfonate
6	C10H15F6N3O4S2	1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide
7	C9H6F20N4O2P2	guanidinium bis(bis(perfluoroethyl)phosphoryl)imide
8	C25H26BN3	guanidinium tetraphenylborate
9	C13H31N3O4S	guanidinium dodecyl sulfate
10	C19H30F13NO3S	tributylmethylammonium tridecafluoro-1-hexanesulfonate
11	C32H35BN2	1-butyl-3-methylimidazolium tetraphenylborate
12	C21H30F20N2O2P2	tributylmethylammonium bis(bis(perfluoroethyl)phosphoryl)imide
13	C37H50BN	tributylmethylammonium tetraphenylborate
14	AgCl	silver chloride
15	C24H20BK	potassium tetraphenylborate
16	H2O	water

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	16 1	Amount concentration (molarity), mol/dm3 - 1 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Liquid - 1	derived from isothermal titration calorimetry data	1
POMD	16 1	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 1; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 2	Molar enthalpy of solution, kJ/mol ; Liquid	Mole fraction - 2; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 3	Amount concentration (molarity), mol/dm3 - 3 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Liquid - 3	derived from isothermal titration calorimetry data	1
POMD	16 3	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 3; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 4	Amount concentration (molarity), mol/dm3 - 4 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Liquid - 4	derived from isothermal titration calorimetry data	1
POMD	16 4	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 4; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	5 16	Amount concentration (molarity), mol/dm3 - 5 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Liquid - 5	derived from isothermal titration calorimetry data	1
POMD	5 16	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 5; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 6	Amount concentration (molarity), mol/dm3 - 6 ; Liquid mixture 1	Temperature, K; Liquid mixture 1 Pressure, kPa; Liquid mixture 1		Liquid mixture 1 Liquid mixture 2	Derived from isothermal titration calorimetry	1
POMD	16 6	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 6; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 7	Amount concentration (molarity), mol/dm3 - 7 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal - 7	derived from isothermal titration calorimetry data	1
POMD	16 7	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 7; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 8	Amount concentration (molarity), mol/dm3 - 8 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal of intercomponent compound 1	derived from isothermal titration calorimetry data	1
POMD	16 8	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 8; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 9	Amount concentration (molarity), mol/dm3 - 9 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal - 9	derived from isothermal titration calorimetry data	1
POMD	16 9	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 9; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	10 16	Amount concentration (molarity), mol/dm3 - 10 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal - 10	derived from isothermal titration calorimetry data	1
POMD	10 16	Molar enthalpy of solution, kJ/mol ; Liquid	Amount concentration (molarity), mol/dm3 - 10; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 11	Molar enthalpy of solution, kJ/mol ; Liquid	Mole fraction - 11; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	12 16	Molar enthalpy of solution, kJ/mol ; Liquid	Mole fraction - 12; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 13	Molar enthalpy of solution, kJ/mol ; Liquid	Mole fraction - 13; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	16 14	Molar enthalpy of solution, kJ/mol ; Liquid	Mole fraction - 14; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Titration calorimetry	1
POMD	15 16	Amount concentration (molarity), mol/dm3 - 15 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal - 15	Derived from isothermal titration calorimetry data	1
POMD	15 16	Molar enthalpy of solution, kJ/mol ; Liquid		Amount concentration (molarity), mol/dm3 - 15; Liquid Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	Titration calorimetry	3

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

solITC: A rapid method to determine solubility products and heats of solution of hydrophobic ionic liquids from in situ synthesis in isothermal titration calorimeter

Ondo, D.[Daniel], Dohnal, V.[Vladimir]

ABSTRACT