Interfacial Properties of C5Pe as an Asphaltene Model Compound

  • Author / Creator
    Bi, Jiebin
  • Water-in-oil (W/O) emulsions create many processing problems in petroleum industry. The enhanced stability of droplets and poor separation of emulsions are often associated with the interfacial accumulation of asphaltenes. The complex nature of asphaltenes has complicated the understanding of their interfacial behavior. Model compounds with well-defined structure and similar water-oil interfacial characteristics have provided an effective route to better understand interfacial behavior and the associated stability of emulsions. In this study, N-(1-hexylheptyl)-N’-(5-carbonylicpentyl) perylene-3,4,9,10-tetracarboxylic bisimide (in brief C5Pe) was used as a model compound for asphaltenes to understand the correlation between interfacial behavior and emulsion stability. It was found that the interfacial properties of C5Pe strongly depend on its concentration and water chemistry. At basic condition, C5Pe exhibited high interfacial activity due to ionization of –COOH groups. At higher C5Pe concentrations, the interfacial films exhibited high elasticity (G’) and mechanical strength, corresponding well with rough and densely-packed film morphology and high emulsion stability. The C5Pe films formed on acidic aqueous phase showed high elasticity although the mechanical strength was low. Meanwhile, these films were less packed, and smoother with high compressibility, resulting in unstable W/O emulsions. Additionally, Ca2+ ions were found to rigidify C5Pe films by connecting C5Pe molecules of ionized –COOH groups at high pH.

  • Subjects / Keywords
  • Graduation date
    Fall 2015
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.