| O/W Microemulsions are ternary systems of oil, water, alcohol (cosurfactant) and surfactant. They allow solubilization of water-insoluble compounds and also shift the pK$sb{rm a}$ values of acids and bases.;In the present work, two types of microemulsions (containing anionic and cationic surfactants) were employed to solubilize a number of sparingly soluble organic acids and bases. Both (acids and bases) were titrated potentiometrically and thermometrically. While potentiometric titrations were useful, they were found to be time consuming. On the other hand, thermometric titrations were rapid and provided results which were comparable to the results obtained by other titrimetric procedures. Also, a computer-interfaced calorimeter was constructed and used to perform thermometric titrations of several compounds solubilized in microemulsions. At higher concentration of analyte, the results were satisfactory but at lower concentrations the resolution of the analog-to-digital (A/D) converter was not sufficient to record all features of the titration curve, resulting in a larger error. |
