Layered Double Hydroxide Intercalated with Sodium Dodecyl Sulfate

Abstract

The study investigates the intercalation of magnesium-aluminum layered double hydroxide with sodium dodecyl sulfate. Monolayer intercalation of the LDH-carbonate was achieved using an acetic acid-assisted ion exchange reaction. The carboxylic acid is believed to assist intercalation of dodecyl sulfate by facilitating the elimination of the carbonate ions present in the anionic clay. Bilayer intercalation was achieved by a coprecipitation method and this resulted in a highly crystalline product. However, in this case the interlayer contains a mixture of dodecyl sulfate anion, sodium dodecyl sulfate and the hydrolysis product dodecanol. The organic phase in the latter product shows an order-disorder transition between 100°C and 120°C, with thermal degradation and volatilization commencing above 170°C.

Keywords:

• Anionic surfactant
• intercalation
• ion exchange reconstruction
• layered double hydroxide

Acknowledgments

This work is based on research supported by the National Research Foundation (NRF) through the Institutional Research Development Programme (IRDP) and the South Africa/Germany Research Collaboration Programme. Financial support from NRF and also from the Bundesministerium für Forschung (BMF) is gratefully acknowledged.