Separation of surfactant mixtures and their homologs by high performance liquid chromatography

A technique for separating similar and diverse ionogenic mixtures into their individual homologs was studied by high performance liquid chromatography on an octadecyl-silica (TSK Gel LS-410) column. Conditions used for the separation were: column size, 6 mm id×200 mm; mobile phase, water/methanol (15:85, v/v) containing (a) 1.0 M sodium perchlorate and adjsting to pH 2.5 with phosphoric acid, (b) 0.1 M and pH 3.5; column temp., 50 C. By using 2 mobile phase conditions, various surfactant mixtures were separated into their individual homologs and simultaneously distinguished from each other, regardless of their ionogenic properties.