Reference number
ISO 3704:1976
ISO 3704:1976
© ISO 2024
International Standard
ISO 3704:1976
Sulphur for industrial use — Determination of acidity — Titrimetric method
Edition 1
1976-09
1976-09
ISO 3704:1976
9179
Published
(Edition 1, 1976)
This publication was last reviewed and confirmed in 2019.
Therefore this version remains current.
Abstract
Applicable to products having acidities, expressed as H2 SO4 , equal to or more than 0.01 % (m/m). Describes the extraction of acidic substances with a mixture of water and propan-2-ol (isopropyl alcohol). Titration of the extract with standard volumetric sodium hydroxide solution in the presence of phenolphthalein as indicator. The preparation of the sample from the laboratory sample is carried out by grinding a sufficient quantity of the undried material until it passes through a sieve of nominal mesh of 250 m.