| Popis: |
A rigorous calorimetric model based on the pseudophase model at infinite diluties was employed to determine the partition coefficient and enthalpy of transfer of 1-pentanol, 3-methyl-1-butanol and benzyl alcohol between the aqueous and micellar phases of sodium dodecyl sulfate (SDDS) at 25 and 45°C. These values are in reasonable agreement with those available in the literature. The effect of temperature on the partition coefficient was found to be small, as opposed to that found for the enthalpy of transfer. An equation is derived for the limiting value of (—d ln m CMC /d m b c ) at m b c = 0 where m b c is the molality of the cosurfactant in the bulk phase. The derivation is based on a rigorous thermodynamic treatment for a pseudophase model. This constant, (—d ln m CMC /d m b c ), contains a number of terms: a partition coefficient, the degree of counter-ion binding, the Setchenov constant, the CMC and the ion—ion interaction parameter for mono-meric surfactant. |
