ISO 4281:1977現行
Sodium hexafluorosilicate for industrial use - Determination of free acidity and total hexafluorosilicate content - Titrimetric method
出版：International Organization for Standardization
專家解讀視頻
Applies to products having contents, expressed as H[2] SiF[6], equal to or more than 0,1 % (m/m). First, determination of the free acid contents by titration of an ice-cooled test portion with a standard volumetric sodium hydroxide solution in the presence of potassium nitrate and using bromothymol blue as indicator, then, followed by titration at near boiling temperature with standard volumetric sodium hydroxide solution to the appearance of a permanent blue colour.
NFT 20 531:1984 - Identical
NBN T 03 526:1983 - Identical
BS 5705-1:1979 - Identical
KS M ISO 4281:2010 - Identical
KS M 1809:2006 - Identical
KS M 1809:2012 - Identical
KS M ISO 4281:2015 - Identical
