Collect. Czech. Chem. Commun. 1985, 50, 1673-1684
https://doi.org/10.1135/cccc19851673

Analysis of mixtures of 4-nitrotoluene-2-sulphonic acid and 4,4'-dinitrostilbene-2,2'-disulphonic acid by tast polarography, differential pulse polarography and thin layer chromatography

Jiří Barek and Ivo Daňhel

Department of Analytical Chemistry, Charles University, 128 40 Prague 2

Abstract

Conditions are sought for the determination of 4-nitrotoluene-2-sulphonic acid (I) and 4,4'-dinitrostilbene-2,2'-disulphonic acid (II) by TAST polarography within the concentration range of 10-2 - 10-6 mol l-1 and by differential pulse polarography (DPP) within the concentration range of 10-3 - 10-8 mol l-1. DPP is applied to the determination of these substances after the thin layer chromatographic separation of their mixtures. Methods are also worked out for their analysis without prior separation, based either on the combined DPP determination of I and the TAST polarographic determination of the sum of I and II in sulphuric acid solutions, or on the DPP determination of the C=C bond in II and the TAST polarographic determination of the sum of the two substances in tetramethylammonium bromide solutions.