Pt/Co scale

The platinum - cobalt color number (short Pt / Co), also APHA - Hazen color number after its inventor Allen Hazen, 1892 designed to investigation of waste water. The samples are colorimetrically in standardized vessels against an acidic solution of potassium hexachloroplatinate (IV ) and cobalt ( II) chloride were compared, which are assigned a color number according to their platinum content between 0 and 500 (mg / L). The method is specific for yellowish stains.

Standardize

The method is described in detail in the following national and international standards:

  • ASTM D 1209 (2005): Standard Test Method for Color of Clear Liquids ( Platinum - Cobalt Scale)
  • BS 5339 (1976): Measurement of Colour on Hazen units ( platinum - cobalt scale )
  • ISO 2211 (1973): A liquid chemical products; Color measurement in Hazen units (platinum cobalt scale)
  • DIN EN ISO 6271 (2005): Determination of the color of clear liquids after the platinum - cobalt scale
Colorimetry (chemical method) Digital Object Identifier
72106
de