ISO 2997:1974

Phosphoric acid for industrial use — Determination of sulphate content — Method by reduction and titrimetry

Applicable to products having sulphate contents equal to or more than 0.0005 % (m/m). Analysis by reduction of the sulphate to sulphide by a mixture of hydriodic acid and hypophosphorus acid. Absorption of the hydrogen sulphide evolved in a mixture of acetone and sodium hydroxide solution. Titration with a standard volumetric solution of mercury(II) acetate in the presence of dithizone as indicator. Has also been approved by the IUPAC.

OEN:

ISO

Langue:

English

Code(s) de l'ICS:

71.060.30

Statut:

Publié

Date de Publication:

1974-10-31

Numéro Standard:

ISO 2997:1974