Adsorption mechanism of n-dodecyl-β-D-maltoside on alumina

Adsorption/desorption behavior of a sugar-based surfactant, n-dodecyl-beta-maltoside, on alumina has been studied and mechanisms involved explored. The surfactant behaves quite differently from nonionic ethoxylated surfactants. In this study, adsorption/desorption of n-dodecyl-beta-maltoside on alumina under different solution conditions (pH and temperature) and in hydrogen bond disrupters (urea and DMSO) was investigated. Electrokinetic measurements of the solid after surfactant adsorption were also carried out. Metal ion-surfactant interactions, as well as maltose-alumina interactions in solution was examined. No evidence of electrostatic interaction or chemical interaction was found between the surfactant and the solid. This is confirmed by the FTIR spectroscopic studies. It is concluded that weak interaction, namely hydrogen bonding, is the main driving force for the adsorption. The results are discussed in terms of the solid and solution properties as well as interactions between the solid and surfactant. (C) 2002 Elsevier Science (USA).