  The study of the modification of interfacial properties between an organic
solvent and aqueous electrolyte solutions is presented by using electrostatic
Dissipative Particle Dynamics (DPD) simulations. In this article the
parametrization for the DPD repulsive parameters aij for the electrolyte
components is calculated considering the dependence of the Flory-Huggins \c{hi}
parameter on the concentration and the kind of electrolyte added, by means of
the activity coefficients. In turn, experimental data was used to obtain the
activity coefficients of the electrolytes as a function of their concentration
in order to estimate the \c{hi} parameters and then the aij coefficients. We
validate this parametrization through the study of the interfacial tension in a
mixture of n-dodecane and water, varying the concentration of different
inorganic salts (NaCl, KBr, Na2SO4 and UO2Cl2). The case of HCl in the mixture
n-dodecane/water was also analyzed and the results presented. Our simulations
reproduce the experimental data in good agreement with previous work, showing
that the use of activity coefficients to obtain the repulsive DPD parameters
aij as a function of concentration is a good alternative for these kinds of
systems.
