ISO International Standard

The sample is hydrolyzed by refluxing under acid conditions. The non-hydrolyzable anionic-active matter is determined by the direct two-phase titration procedure describes in ISO 2271. This method is applicable to the determination of cyclic sulphonates in alkylphenol ether sulphates and of small amounts of sulphonates in sulphated fatty alcohols. The molar mass of the anionic matter must be known or previously determined, if its content is expressed as percentage by mass.