Etude de l'application de l'isonitrosomalonylguanidine au dosage du fer dans les alliages d'aluminium et dans les zincs et au dosage du cobalt dans les aciers

Isonitrosomalonylguanidine reacts with iron salts in acid medium (pH ca. 6) ; or in basic medium (pH ca. 9), giving a blue color. This reaction is the basis of a new method for the determination of iron. in aluminium alloys (in acid medium) or in zincs (in acid medium or in basic medium) for the weakest contents. Concerning the determination of cobalt in steels, bromine can be used instead of nitric acid, in order to remove the excess of reagent.