Turbidimetric analysis of amine oxides and amine oxide‐anionic surfactant mixtures

Abstract Automatic turbidimetric analysis has been shown to be a simple and accurate method to determine the actives in anionic surfactants as well as the actives in amine oxides. This technique has been applied to dilute solutions of these surfactants in the μM range. Solutions containing mixtures of anionic surfactants and amine oxides can be positively resolved by turbidimetric titration without interferences. Performing two titrations at different pH values ensures that the amine oxide is completely in its nonionic form or totally protonated and behaving as a cationic surfactant.