ABSTRACT

The Taylor dispersion technique has been used for measuring limiting binary mutual diffusion coefficients of octanoic acid and sodium octanoate at T = 298.15 K (D0), respectively, using water as carrier solution, and different injections solutions from (0.75 to 100) 10 3 mol dm 3. These D0 values, together with the Stokes Einstein equation, were used to determine the equivalent hydrodynamic radii, Rh, at infinitesimal concentration of these species (octanoic acid and sodium octanoate). In addition, the limiting diffusion coefficients of the molecular (D0 m) and dissociated (D0+- ) forms of the octanoic acid were estimated. We have also investigated the diffusion properties for a system containing octanoic acid, a-cyclodextrin (a-CD) and water. From these results, we have estimated the percentages of free (C7COOH) and associated forms of octanoic acid (a-CD/C7COOH) and the equilibrium constant, K, for a supramolecular host guest complex between octanoic acid and a-CD.

Compounds

#	Formula	Name
1	C36H60O30	.alpha.-cyclodextrin
2	C8H15NaO2	sodium octanoate
3	C8H16O2	octanoic acid
4	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	2 4	Binary diffusion coefficient, m2/s ; Liquid	Amount concentration (molarity), mol/dm3 - 2; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	Taylor dispersion method	5
POMD	3 4	Binary diffusion coefficient, m2/s ; Liquid	Amount concentration (molarity), mol/dm3 - 3; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	Taylor dispersion method	6
POMD	3 4 1	Binary diffusion coefficient, m2/s ; Liquid	Amount concentration (molarity), mol/dm3 - 3; Liquid Amount concentration (molarity), mol/dm3 - 1; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Liquid	Taylor dispersion method	10
POMD	4 1	Binary diffusion coefficient, m2/s ; Liquid	Amount concentration (molarity), mol/dm3 - 1; Liquid Pressure, kPa; Liquid Temperature, K; Liquid		Liquid	Taylor dispersion method	1

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Limiting diffusion coefficients of sodium octanoate, and octanoic acid in aqueous solutions without and with .alpha.-cyclodextrin

Filho, C. M. C.[Cesar M.C.], Verissimo, L. M. P.[Luis M. P.], Valente, A. J. M.[Artur J.M.], Ribeiro, A. C. F.[Ana C. F.]

ABSTRACT