Molecular Dynamics of Decane Solubilization and Diffusion of Aggregates Consisting of Surfactant and Decane Molecules in Aqueous Solutions

All-atom molecular dynamics has been employed to study the processes of self-aggregation and solubilization in aqueous solutions that contain decane, ionic and nonionic surfactants, and additives of salts. In particular, micellization of an anionic surfactant (sodium dodecyl sulfate) in an aqueous solution has been simulated in the presence of a hydrocarbon (decane) at preset temperature and pressure and different initial surfactant and hydrocarbon concentrations in the solution. Moreover, self-aggregation has been simulated in systems containing water, decane, and a mixture of anionic (sodium dodecyl sulfate) and nonionic (hexaethylene glycol monodecyl ether, C10E6) both in a salt-free solution and in the presence of sodium chloride, calcium chloride, or a mixture thereof. Diffusion coefficients have been calculated for aggregates consisting of hydrocarbon and surfactant aggregates, and the viscosities of corresponding aqueous solutions have been estimated. The viscosities have been calculated in simulation cells containing either one or several aggregates.