Simulation of the Supramolecular Structure of Petroleum Disperse Systems

Abstract

The formation of predominant structures of supramolecular entities in highly dispersed colloidal systems, the dispersion phase of which is represented by hydrocarbons, has been studied using molecular mechanics (MM+) simulation. The character of structuring in both individual groups of molecules and their mixtures yielding energetically most stable associates of supramolecular structures has been investigated for compounds taken to model paraffinic, naphthenic, and asphaltenic petroleum components. It has been shown that the number of identical molecules (n) in the associates is limited. For example, asphaltene molecules form an associate with an ordered (graphite-like) supramolecular structure at n ≈ 5–10. Consideration of a mixture of three components with regard to the values of intermolecular interaction energy E_IMI shows that in colloidal solutions, asphaltenes form a core to which naphthenic and paraffin hydrocarbons are coordinated.