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A Mesoscopic Model for an Asphaltene and Complex Mixtures of Asphaltenes
Petroleum Science and Technology, 2015A representation for an asphaltene system and asphaltene mixtures is proposed based on experimental data reported by Socrates et al. These were modeled at the mesoscopic level by applying dissipative particle dynamics (DPD), where DPD beads correspond to the main structure that constitutes the real asphaltene fraction.
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Squalene in Petroleum Asphaltenes
Science, 1981Squalene, 2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene, a new biological marker, has been detected in various petroleum asphaltenes and their pyrolysis products. Since squalene is the most common triterpenoid in nature and the biological precursor of the important tetra- and pentacyclic triterpane markers, its detection in asphaltene ...
Douglas S. Montgomery +4 more
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Effect of Asphaltene Concentration on the Aggregation and Precipitation Tendency of Asphaltenes
Energy & Fuels, 2014Destabilized asphaltenes can easily adhere to the oil well production equipment, the transportation pipelines, and also the refining and storage facilities, resulting in significant remediation costs. Therefore, it is of great importance to the energy industry to understand the factors that govern the kinetics of asphaltene aggregation and ...
Haji-Akbari Nasim +2 more
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Stability and Aggregation of Asphaltenes in Asphaltene−Resin−Solvent Mixtures
Energy & Fuels, 2004The Integral Equation Theory (IET) of fluids and molecular dynamics (MD) simulations have been used to study the stability and aggregation of asphaltenes in asphaltene−resin mixtures with different host solvents (n-heptane, toluene, and pyridine).
Y. Duda +3 more
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Asphaltenes: The Cholesterol of Petroleum
Proceedings of Middle East Oil Show, 1995ABSTRACT Asphaltene precipitation and deposition has been recognized to be a significant problem in oil production, transmission, and processing facilities. The precipitation of asphaltenes is caused by a number of factors including changes in pressure, temperature, chemical composition of the crude oil, mixing the oil with diluents or ...
Selim G. Sayegh, Sunil Kokal
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Self-assembly of resins and asphaltenes facilitates asphaltene dissolution by an organic acid [PDF]
Journal of Colloid and Interface Science, 2013 Asphaltene precipitation occurs in petroleum fluids under certain unfavorable conditions, but can be controlled by tuning composition. Aromatic solvents in large quantities can prevent precipitation entirely and can dissolve already precipitated asphaltenes.
Abbas Firoozabadi, Sara M. Hashmi
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Petroleum Science and Technology, 1998
ABSTRACT We report x-ray scattering measurements on asphaltenes and bitumen solutions, with attention to the concentrated regimes. We characterize the data in terms of a correlation length which is indicative of proximity to phase separation in a mixture, rather than the radius-of-gyration more indicative of individual colloids.
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ABSTRACT We report x-ray scattering measurements on asphaltenes and bitumen solutions, with attention to the concentrated regimes. We characterize the data in terms of a correlation length which is indicative of proximity to phase separation in a mixture, rather than the radius-of-gyration more indicative of individual colloids.
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The Fractal Aggregation of Asphaltenes
Langmuir, 2013This paper discusses time-resolved small-angle neutron scattering results that were used to investigate asphaltene structure and stability with and without a precipitant added in both crude oil and model oil. A novel approach was used to isolate the scattering from asphaltenes that are insoluble and in the process of aggregating from those that are ...
Claudio Vilas Boas Favero +3 more
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Asphaltene Characterization: Sensitivity of Asphaltene Properties to Extration Techniques
Canadian International Petroleum Conference, 2001Abstract One step in asphaltene extraction is to wash the precipitated asphaltenes with the precipitant to remove trapped resinous material. To assess the effect of washing on asphaltene properties, asphaltenes were extracted with three different degrees of washing.
Harvey W. Yarranton +3 more
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Energy & Fuels, 2018
The aggregates of asphaltene and resin molecules play an important role in stabilizing heavy crude oil. Although many experiments are applied to investigate the complex aggregating structure of asphaltene and resin molecules in heavy crude oil, those ...
S. Song +5 more
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The aggregates of asphaltene and resin molecules play an important role in stabilizing heavy crude oil. Although many experiments are applied to investigate the complex aggregating structure of asphaltene and resin molecules in heavy crude oil, those ...
S. Song +5 more
semanticscholar +1 more source