Comparative studies on compounds occluded inside asphaltenes hierarchically released by increasing amounts of H2O2/CH3COOH

J. Zhao (1, 2) , Z. Liao Zewen (2) , L. Zhang (2) , Patrice Creux (1) , C. Yang (3) , Anna Chrostowska (4) , H. Zhang (5) , Alain Graciaa (1)

1 TEFC - Thermodynamique et Energétique des fluides complexes
2 State Key Laboratory of Organic Geochemistry
3 Guangzhou Marine Geological Survey
4 IPREM - Institut pluridisciplinaire de recherche sur l'environnement et les matériaux
5 Institute of Petroleum Exploration and Development

Being the heaviest fraction of crude oils, asphaltenes are liable to aggregate, and other molecules in the oils can be steadily adsorbed onto, and even occluded inside the macromolecular structures of the asphaltenes. These occluded compounds inside the asphaltenes can survive over geological time in oil reservoirs owing to effective protection by the macromolecular structures of the asphaltenes. The asphaltenes of a crude oil (ZG31) from the central Tarim Basin, NW China, were hierarchically degraded by increasing the amount of H2O2/CH3COOH to release the occluded compounds. Besides the common components, series of even numbered n-alk-1-enes and 3-ethylalkanes were detected among the occluded compounds. Comparison of the biomarker distributions and the compound-specific C isotopic results between the compounds from the maltenes and those from the occluded fraction, the ZG31 reservoir was suggested to have been charged multiple times, with different charges being derived from different strata of source rocks.

Mots clés: Biomarker distributions; Central Tarim Basin; Comparative studies; Macromolecular structures; Maltenes; NW China; Oil reservoirs; Source rocks Engineering controlled terms: Biomarkers; Macromolecules; Petroleum reservoir engineering Engineering main heading: Asphaltenes GEOBASE Subject Index: asphaltene; carbon isotope; carboxylic acid; comparative study; crude oil; geological time; hydrocarbon reservoir; hydrogen peroxide; reservoir; source rock Regional Index: China; Tarim Basin; Xinjiang Uygur

Domaines: Chimie-Physique [physics.chem-ph]

J. Zhao, Z. Liao Zewen, L. Zhang, Patrice Creux, C. Yang, et al.. Comparative studies on compounds occluded inside asphaltenes hierarchically released by increasing amounts of H2O2/CH3COOH. Applied Geochemistry, 2010, 25 (9), pp.1330-1338. ⟨10.1016/j.apgeochem.2010.06.003⟩. ⟨hal-00687251⟩