Volumetric determination of styphnates with methylene blue

Abstract

A modification of Bolliger's extraction titration of o-polynitrophenols with methylene blue is described. Because of its better solvent power, nitrobenzene has been used as the extracting agent instead of chloroform, which would necessitate repeated renewal during the titration. The method is applied to the determination of lead styphnate and of the intermediates and effluents in its production, as well as to the analysis of priming compositions. Nitrate interference is removed by extracting the styphnic acid with isobutyl methyl ketone before the titration.