The application of hydrogen/palladium and deuterium/palladium electrodes as indicator electordes in the potentiometric titrations of acids in propylene carbonate

摘要

The application of the electrode couples (H_2/Pd)_(ind)-(H_2/Pd)_(ref) and (D_2/Pd)_(ind)-(H_2/Pd)_(ref) in the potentiometric titrations of acids in propylene carbonate was investigated. The following acids and acid mixtures were titrated: mineral acids (perchloric and nitric acid); monocarboxylic acids (acetic, benzoic and 3,4-dinitrobenzoic acid); dicarboxylic acids (phthalic, fumaric and oxalic acid) and mixtures (benzoic + phthalic acid, phathalic + oxalic acid and oxalic + fumaric acid). The titrations were carried out with a standard solution of potassium hydroxide in methanol. It was found that (H_2/Pd)_(ind) and (D_2/Pd)_(ind) elecrtrodes behave in a similar manner and that both can be successfully applied to the determination of acids in propylene carbonate. The relative error of the determination was about 1%.