New aspects of the asphaltene precipitation via interfacial tension measurement

ABSTRACT

In present study, the asphaltene precipitation was examined through pendant drop method regarding the impacts of oil composition, solvent type and concentration in both atmospheric and elevated pressures. Consequently, it is observed that there is a specific region for solvent concentration, in which the surface activity of nC₅ is more than nC₇ leading to the lower oil-water interfacial tension of nC₅ diluted oil than that of nC₇ diluted solutions. By decreasing resin to asphaltene ratio, this region will shift to the lower solvent concentrations. This finding could be of crucial value for analyzing the asphaltene precipitation in petroleum systems.

KEYWORDS:

• asphaltene precipitation
• Interfacial tension
• solvent
• crude oil composition
• SARA analysis