Numéro de référence
ISO 3331:1975
ISO 3331:1975
© ISO 2024
ISO 3331:1975
Nitrate d'ammonium à usage industriel — Dosage de l'azote total — Méthode titrimétrique après distillation
Edition 1
1975-07
1975-07
Annulée
Résumé
Based on the conversion of nitrate into ammonia by means of Devarda's alloy in alkaline solution together with the liberation of ammonia from ammonium ions. Distillation of the ammonia from both reactions, absorption in an excess of standard volumetric sodium hydroxide solution in the presence of methyl red/methylene blue mixed indicator. A typical distillation apparatus is shown in a figure.