Probing Order in Asphaltenes and Aromatic Ring Systems by HRTEM

Abstract

Recent findings regarding the controversy surrounding asphaltene molecular weight coupled with increasing understanding of their molecular structure has enabled the understanding of asphaltene properties. It has been shown previously that larger ring systems require more alkane substituents to maintain a balance between ring stacking propensity vs steric repulsion. Here, stacking and its disruption in asphaltenes and aromatic ring systems are explored using high-resolution transmission electron microscopy (HRTEM). It is shown that molecularly disparate asphaltenes exhibit stacking invariants. Solubility data herein suggests these stacking invariants naturally follow from the solubility classification of asphaltenes.