Sulphonated hydrocarbons with any other anionic

General. Acid-hydrolyse by the appropriate method and determine the surviving titratable surfactant (sulphonated hydrocarbon) or one of the hydrolysis products. 

With alkyl sulphate, alkylether sulphate or alkylphenyl ether sulphate. Acid hydrolysis (section 2.4.2). Then any of the following. 

Extraction of fatty alcohol with petroleum ether (section 5.3.2), or of 

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