Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9675843 | Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2005 | 9 Pages |
Abstract
An improved model of ionic surfactant adsorption was applied for description of CTABr (cetyltrimethylammonium bromide), CTACl and CTAHSO4 surfactants adsorption from their aqueous solutions containing KCl and KBr at liquid/air interface. The model is based on the assumption that the surfactant ions and their counterions undergo non-equivalent adsorption within the Stern layer. The surface tension isotherms for various concentrations of surfactant ions and Brâ and Clâ counterions were calculated and compared with the results of surface tension measurements performed by the pendant drop shape analysis methods. The dependences of surface excess values of all ions on CTA+/Brâ/Clâ bulk concentrations were calculated. Obtained results showed much larger affinity to the interface of Brâ anions than Clâ anions. This was explained in terms of a larger repulsion of chloride anions from the interface than bromide anions. It may be caused by the difference in their excess polarizability and the van der Waals interaction with the interface.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Colloid and Surface Chemistry
Authors
G. Para, E. Jarek, P. Warszynski,