Open AccessCoulometric titrations of bases in propylene carbonate and γ-butyrolactone using hydroquinone as the depolarizer and a quinhydrone indicator electrode
Author(s) -
Lj. Jakšić,
Radmila M. Džudović,
R. Mihajlović,
Zorka Stanić
Publication year - 2000
Publication title -
journal of the serbian chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.227
H-Index - 45
eISSN - 1820-7421
pISSN - 0352-5139
DOI - 10.2298/jsc0008587j
Subject(s) - quinhydrone electrode , coulometry , chemistry , potentiometric titration , propylene carbonate , hydroquinone , inorganic chemistry , standard hydrogen electrode , titration , electrode , reference electrode , electrochemistry , organic chemistry
The application of hydroquinone for the coulometric generation of hydrogen ions in propylene carbonate (PC) and ?-butyrolactone (GBL) is described. The current-potential curves recorded for this depolarizer, titrated bases, indicator and the solvents used showed that the investigated depolarizer is oxidized at lower potentials than the oxidation potentials of other components in the solution. The hydrogen ions generated by the oxidation of hydroquinone were used for the titration of organic bases (triethylamine, n-butylamine, pyridine, quinoline, aniline, N,N'-diphenylguanidine, piperidine, and 2,2?-bi?pyridine) in PC and GBL with with visual (Crystal Violet as indicator) and potentiometric end-point detection using a quinhydrone electrode as the indicator electrode. The quinhydrone added to the to be analyzed solution served both as a source of hydrogen ions and, together with the immersed platinum electrode, as a quinhydrone electrode. The relative error of the determination of the bases was about 1%.