Abstract

Molecular dynamics simulations were performed to investigate the adsorption of dodecylamine (DDAH), oleate (NaOL) and the mixture of the two ions on a muscovite surface in an aqueous solution. The results indicate that DDAH molecules absorb on the muscovite surface by electrostatic interactions and hydrogen bonding. In contrast, NaOL molecules cannot independently adsorb on the muscovite surface. A micelle structure of DDAH and NaOL molecules forms on the muscovite surface. The DDAH molecules are determined to play a dominant role in the adsorption of the mixed surfactants on the muscovite surface, while the NaOL molecules co-adsorb with the DDAH molecules. Sodium ions also play an important role in the adsorption of the mixed surfactants. This paper may provide a template for studying the adsorption configuration and mechanism of mixed surfactants on mineral surfaces.