Abstract 

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.


General information

  • Status :  Withdrawn
    Publication date : 1986-12
  • Edition : 1
  • :
    ISO/TC 134
    Fertilizers, soil conditioners and beneficial substances
  • 65.080
    Fertilizers

Life cycle

A standard is reviewed every 5 years



Revisions / Corrigenda

  • Now withdrawn
    ISO 5310:1986

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