ISO 3709:1976
Phosphoric acid for industrial use (including foodstuffs) — Determination of oxides of nitrogen content — 3,4- Xylenol spectrophotometric method
Reference number
ISO 3709:1976
Edición 1
1976-11
Retirada
ISO 3709:1976
9184
Retirada (Edición 1, 1976)

Resumen

Applicable to products having a content, expressed as N, equal to or more than 0.2 mg/kg. Consists in oxidation of nitrous nitrogen to nitric nitrogen by potassium permanganate and reaction of nitrogen(V) with 3,4-xylenol under specified conditions to form a nitrate derivative. Subsequent destillation of the nitrate derivative and absorption in sodium hydroxide solution. Spectrophotometric measurement of the yellow nitrophenol at a wavelength of about 435 nm.

Informaciones generales

  •  : Retirada
     : 1976-11
    : Retirada de la Norma Internacional [95.99]
  •  : 1
     : 4
  • ISO/TC 47
  • RSS actualizaciones

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