Reference number
ISO 6228:1980
ISO 6228:1980
© ISO 2025
International Standard
ISO 6228:1980
Chemical products for industrial use — General method for determination of traces of sulphur compounds, as sulphate, by reduction and titrimetry
Edition 1
1980-11
1980-11
ISO 6228:1980
12505
Published
(Edition 1, 1980)
This publication was last reviewed and confirmed in 2022.
Therefore this version remains current.
Abstract
Describes a method based on prior conversion of the sulphur compounds in a test portion to sulphate, if required, and reduction of the sulphate ions ti hydrogen sulphide by a mixture of hydriodic and phosphinic acids in the presence of hydrochloric acid. The hydrogen sulphide is entrained in a current of nitrogen and absorbed in a solution of sodium hydroxide in aqueous acetone, followed by titration of the sulphide ions with standard volumetric mercury(II) acetate or nitrate solution in the presence of 1,5-diphenyl-3-thiocarbazone (dithiozone) as indicator.