Characterization of Asphaltene Building Blocks by Cracking under Favorable Hydrogenation Conditions

The chemical building blocks that comprise petroleum asphaltene molecules were determined by thermal cracking of samples under conditions that minimized alterations to aromatic and cycloalkyl groups. Favorable hydrogenation conditions that used tetralin as a hydrogen-donor solvent and an iron-based catalyst allowed asphaltenes derived from different crude oils to yield approximately 50–60 wt % distillates (<538 °C fraction), with coke yields below 10 wt %, and reach conversions of the vacuum residue fraction between 65 and 75 wt %. Products in a wide range of boiling points, from naphtha to heavy material in the vacuum residue range, were observed by simulated distillation. Quantitative recovery of the cracked products, with mass balances above 96%, and characterization of the distillate fraction by gas chromatography–field ionization–time-of-flight high-resolution mass spectrometry (GC–FI–TOF HR MS) provided information on the abundance of building blocks, including saturates, 1–3-ring aromatics, 4+-ring...