Adsorption of metallic ions from aqueous solution on surfactant aggregates: a molecular dynamics study

Abstract

Metallic ion adsorption on surfactant aggregates were studied with Molecular dynamics simulations. Using ionic salts, such as lead sulfate (PbSO4) and aluminum sulfate [Al2(SO4)3], adsorption of lead and aluminum were investigated at different salt concentrations and different surfactant aggregates (micelles) sizes. The micelles were constructed with spherical shapes composed of sodium dodecyl sulfate (SDS) anionic surfactants. The electrostatic interactions between the positive ions and the negative SDS headgroups promote capture of the metal particles on the aggregate surface. Metal adsorption was analyzed in terms of radial density profiles, partial pair distribution functions and adsorption isotherms. It is showed that SDS micelles adsorb better lead than aluminum ions regardless of the size of the aggregates and salt concentrations.

Electric Fields Applied to Surfactant Molecules for Enhancing Removal of Hydrocarbons from a Solid Surface: A Molecular Dynamics Study

“…For instance, Hu et al studied adsorption of dodecylsulfobetaine zwitterionic molecules on a silica surface, and Liu et al investigated dodecane desorption from the same silica surface in an aqueous dilution using hexadecyltrimethylammonium bromide (CTAB) surfactants . Moreover, retention of metallic particles in aqueous solutions , and adsorption of organic molecules on solid surfaces using sodium dodecyl sulfate (SDS) surfactants have been recently studied …”