ISO 3701:1976
Anhydrous hydrogen fluoride for industrial use; Determination of hexafluorosilicic acid content; Reduced molybdosilicate photometric method
- Standard No.
- ISO 3701:1976
- Release Date
- 1976
- Published By
- International Organization for Standardization (ISO)
- Status
- 2002-05
- Latest
- ISO 3701:1976
- Scope
- Applicable to products having H2 SiF6 contents between 0.01 % (m/m) and 0.2 % (m/m). Gives introductory instructions to the risk in handling with the product. The principle of analysis consists in formation of oxidized molybdosilicate (yellow) in weakly acid medium in the presence of boric acid to suppress interference by fluorine. Selective reduction of this complex after addition of sulphuric acid solution and oxalic acid to eliminate interference from phosphates. Photometric measurement of the blue coloured complex at a wavelength of about 795 nm.
ISO 3701:1976 history
- 1976 ISO 3701:1976 Anhydrous hydrogen fluoride for industrial use; Determination of hexafluorosilicic acid content; Reduced molybdosilicate photometric method
