Cancellation of dipole moment of models of asphaltene aggregates as a mean for their dispersion in toluene and THF calculated using molecular dynamics.

• Asphaltene aggregate stability in crude oils and the association with dipolar moment. • The behavior of asphaltene subfractions A1 and A2 and the impact of their structure in aggregate formation and stability. • Direct consequence of the zero dipolar moment of the aggregates with their stability in solution. The study of the behavior of asphaltenes in solution has focused on their tendency to form aggregates and less importance has been given to describing and understanding what allows the formation of asphaltene aggregates that remain stably dispersed. Using molecular dynamics simulations, we calculated that the dipole moment of models for asphaltene aggregate tends to zero when the number of molecules in the aggregate tends to large values. In other words, such dipole moment cancellation would be an important contributor to the dispersion of these aggregates. [ABSTRACT FROM AUTHOR]