Fertilizers -- Determination of potassium content -- Titrimetric method
The method consists in precipitating of potassium ions by an excess of sodium tetraphenylborate (NaTPB) in a weakly alkaline medium, filtrating and determing of the unused NaTPB by back titration with cetyltrimethylammoniumbromide solution. The test solution shall be prepared as specified in ISO 5317 or ISO 7407.
A standard is reviewed every 5 years
Revisions / Corrigenda