ISO 5930:1979
Cryolite, natural and artificial, and aluminium fluoride for industrial use; Determination of phosphorus content; Reduced molybdophosphate photometric method
- Standard No.
- ISO 5930:1979
- Release Date
- 1979
- Published By
- International Organization for Standardization (ISO)
- Latest
- ISO 5930:1979
- Scope
- Specifies a method applicable to products having phosphorus contents equal to or greater than 0,002 % (m/m). The principle is based on alkaline fusion of a test portion with a mixture of sodium carbonate and boric acid, dissolution of the fused mass in nitric acid, neutralization of suitable aliquot portion with sodium hydroxide solution, reaction with acid ammonium molybdate solution to form a molybdophosphate complex, reduction by a mixture of sodium disulphite and 4-amino-3-hydroxynaphtalene-1-sulphonic acid, and photometric measurement of the reduced complex.
ISO 5930:1979 history
- 1979 ISO 5930:1979 Cryolite, natural and artificial, and aluminium fluoride for industrial use; Determination of phosphorus content; Reduced molybdophosphate photometric method
