Dynamic adsorption of cetyl trimethyl ammonium bromide at decane/water interface

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2015-11, Vol.484, p.313-317
• Main Authors: Salamah, Abdulsalam, Phan, Chi M., Pham, Hung G.
• Format: Article
• Language: English
• Subjects: CTAB; Decane/water interface; Dynamic surface tension; Pendant drop method
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2015.08.010

[Display omitted] •Dynamic adsorption of CTAB at decane/water interface was measured.•The surface tension was modelled by a new modelling framework.•The new model does not require the Gibbs equation and produce a unique solution.•The obtained data indicated that CTA+ are moved away from monolayer arrangement due to interaction with decane in the interface. The dynamic adsorption of cetyl trimethyl ammonium bromide (CTAB) was investigated at decane/water interface by pendant drop technique. The images were analysed using Axisymmetric Drop Shape Analysis software and then were modelled using a new model. The model provided a unique solution for equilibrium adsorption. Consequently, dynamic data at two different concentrations were fitted simultaneously to determine the adsorption parameters. Good fittings have been achieved and then applied to predict dynamic tension at other concentrations. The outcomes revealed a significant increment in term of interfacial adsorption in comparison with adsorption at the air/water interface. The nature of this increment can be explained by considering the impacts of hydrophobic oil molecules and interfacial layer arrangements of alkane/water interfaces. The results can be used to quantify the interaction between alkane and the hydrocarbon tail of ionic surfactants at the oil/water interface.