Sodium fluoride for industrial use — Determination of fluorine content — Modified Willard-Winter method

Available format(s)

Hardcopy , PDF , PDF 3 Users , PDF 5 Users , PDF 9 Users

Language(s)

English, French

Published date

12-01-1973

Publisher

International Organization for Standardization

The principle consists in separation of the fluorine from a test portion by distillation with sulphuric acid or perchloric acid. Titration with thorium nitrate solution using sodium alizarinsuphonate and methylene blue as indicators. Alternatively the thorium nitrate titration may be carried out using sodium alizarinsuphonate alone as indicator, the end-point being determined spectrophotometrically under carefully defined conditions. The absorbance at a wavelength of 525 nm shall reach the arbitrary value of 0.6. Has also been approved by the IUPAC.

Committee	ISO/TC 47
DocumentType	Standard
Pages	5
PublisherName	International Organization for Standardization
Status	Current

Standards	Relationship
NFT 20 151 : 84 FD	Identical
NBN T 03 463 : 1983	Identical
PN ISO 2833 : 1998	Identical
BS 5072-3:1975	Similar to

EN 12173:2012	Chemicals used for treatment of water intended for human consumption - Sodium fluoride
DIN EN 12173:2013-01	CHEMICALS USED FOR TREATMENT OF WATER INTENDED FOR HUMAN CONSUMPTION - SODIUM FLUORIDE
I.S. EN 12173:2012	CHEMICALS USED FOR TREATMENT OF WATER INTENDED FOR HUMAN CONSUMPTION - SODIUM FLUORIDE
12/30258194 DC : 0	BS EN 12173 - CHEMICALS USED FOR TREATMENT OF WATER INTENDED FOR HUMAN CONSUMPTION - SODIUM FLUORIDE
UNI EN 12173 : 2013	CHEMICALS USED FOR TREATMENT OF WATER INTENDED FOR HUMAN CONSUMPTION - SODIUM FLUORIDE
PREN 12173 : DRAFT 2012	CHEMICALS USED FOR TREATMENT OF WATER INTENDED FOR HUMAN CONSUMPTION - SODIUM FLUORIDE
UNE-EN 12173:2013	Chemicals used for treatment of water intended for human consumption - Sodium fluoride
BS EN 12173:2012	Chemicals used for treatment of water intended for human consumption. Sodium fluoride