ISO 848:1981
Phosphoric acid for industrial use; Determination of calcium content; Titrimetric method
- Standard No.
- ISO 848:1981
- Release Date
- 1981
- Published By
- International Organization for Standardization (ISO)
- Status
- 2002-05
- Latest
- ISO 848:1981
- Scope
- The general method is applicable to phosphoric acid not containing polyphosphoric acids and to products having a calcium content equal to or greater than 0.020 % (m/m). In special cases a preliminary hydrolysis of polyphosphoric acids is carried out by prolonged boiling in the presence of hydrochloric acid. Precipitation of calcium as calcium oxalate at pH 4 0.3, filtration of the precipitate, dissolution in hydrochloric acid and re-precipitation under the same operating conditions in order to purify the precipitate. Oxidimetric titration in sulphuric acid solution by means of potassium permanganate. - Cancels and replaces ISO Recommendation R 848-1968.
ISO 848:1981 history
- 1981 ISO 848:1981 Phosphoric acid for industrial use; Determination of calcium content; Titrimetric method
