Reference number
ISO 3332:1975
ISO 3332:1975
© ISO 2024
International Standard
ISO 3332:1975
Ammonium sulphate for industrial use — Determination of ammoniacal nitrogen content — Titrimetric method after distillation
Edition 1
1975-07
1975-07
ISO 3332:1975
8597
Published
(Edition 1, 1975)
This publication was last reviewed and confirmed in 2019.
Therefore this version remains current.
Abstract
Based on dissolution of a test sample in water, distillation of the ammonia after displacement by an alkali solution. Absorption in an excess of standard volumetric sulphuric acid solution and back-titration with standard volumetric sodium hydroxide solution in the presence of methyl red/methylene blue mixed indicator. A typical distillation apparatus is shown in a figure.