On Plate Resolution of Three-Component Mixture of Cationic Surfactants with Mixed Aqueous-Organic Eluents Containing Formate Ion

Abstract

The chromatography of three long chain aliphatic quaternary ammonium halides (cationic surfactants) was performed on kieselguhr layers using different solvent systems. The mutual separation of dodecyltrimethylammonium bromide (DTAB), tetradecyltrimethylammonium bromide (TTAB), and hexadecyltrimethylammonium chloride (HTAC) was achieved with the solvent system methanol: 10% aqueous sodium formate (30:70, v/v) on kieselguhr layer. The effect of nature of alkane chain length of alcohols on the mobility of DTAB, TTAB, and HTAC and also the effect of formate ion substituted by acetate ion and benzoate ion of sodium acetate and sodium benzoate respectively on the mobility of these surfactants were studied. The effect of the nature of different adsorbents (kieselguhr, silica gel, and alumina) on the mobility of DTAB, TTAB, and HTAC was also studied. The interference of metal cations as impurities on the resolution of mixture of DTAB, TTAB, and HTAC was also examined. The limits of detection of DTAB, TTAB, and HTAC estimated were 3.3, 3.1, and 2.8 µg/zone respectively. The developed method was utilized to separate these surfactants from different spiked water samples.

Keywords:

• Dodeyltrimethylammonium bromide
• hexadecyltrimethylammonium chloride
• kieselguhr
• separation
• tetradecyltrimethyammonium bromide
• thin-layer chromatography

ACKNOWLEDGMENTS

The authors are grateful to the Chairman, Department of Applied Chemistry, A.M.U., Aligarh for providing necessary research facilities. One of the authors (S.A. Bhawani) is thankful to the University Grants Commission, New Delhi (India) for financial assistance.