Coulometric titrations of bases in propylene carbonate using hydrogenpalladium and deuteriumpalladium generator electrodes

• Published in: Talanta (Oxford) 1992-12, Vol.39 (12), p.1587-1590
• Main Authors: Mihajlović, Randel P., Jakšić, Ljiljana N., Vajgand, Vilim V.
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Chemistry; Electrochemical methods; Exact sciences and technology
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/0039-9140(92)80188-J

The application of hydrogen and deuterium ions obtained by anodic oxidation of hydrogen and deuterium dissolved in palladium, for the coulometric determination of bases (both individual and in mixtures) in propylene carbonate, is described. The current-potential curves at a palladium anode for supporting electrolyte indicator, titrated bases, hydrogen dissolved in palladium and deuterium dissolved in palladium showed that hydrogen and deuterium are oxidized at much less positive potentials than the oxidation potentials of other substances present in the solution. The generated H + and D + ions were used for the titration of bases (pyridine, quinoline, triethylamine, n-butylaniline, 2,2′-dipiridyl and aminopyrine) with visual and potentiometric detection. The oxidation of hydrogen and deuterium proceeded with 100% current efficiency. Two-component mixtures of bases (aliphatic + aromatic amine) were titrated successfully by using two indicators, Eosin and Crystal Violet. The relative error of the determination with respect to each individual base determination, was less than 2.5% for quantities of bases ranging from 1 to 3 mg.