Reference number
ISO 3331:1975
ISO 3331:1975
© ISO 2024
ISO 3331:1975
Ammonium nitrate for industrial use — Determination of total nitrogen content — Titrimetric method after distillation
Edition 1
1975-07
1975-07
Retirada
Resumen
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.