The method consists in preparing of a test solution as specified in ISO 5317, precipitating of potassium ions by sodium tetraphenylborate in a weakly alkaline medium in the presence of disodium ethylenediaminetetraacetate dihydrate (EDTA, disodium salt) and formaldehyde, followed by filtrating of the precipitate, drying and weighing.

General information

  • Status :  Withdrawn
    Publication date : 1983-12
  • Edition : 1
    Number of pages : 3
  • :
    ISO/TC 134
    Fertilizers, soil conditioners and beneficial substances
  • 65.080

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