Small angle X-ray scattering study of the effect of pressure on the aggregation of asphaltene fractions in petroleum fluids under near-critical solvent conditions

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Langmuir; (United States)

DOI:https://doi.org/10.1021/la00032a023· OSTI ID:5827303

Carnahan, N F; Quintero, L ^[1]; Pfund, D M; Fulton, J L; Smith, R D ^[2]; Capel, M ^[3]; Leontaritis, K ^[4]

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1. Rice Univ., Houston, TX (United States)
2. Pacific Northwest Lab., Richland, WA (United States)
3. Brookhaven National Lab., Upton, NY (United States)
4. Core Lab., Houston, TX (United States)

Small angle X-ray scattering was used to determine the effect of pressure on the extent of asphaltene aggregation for a system under near-critical conditions. A mixture containing 60 vol% Crude Oil A in n-pentane was studied at 110[degree]C, at pressures ranging from 25 to 400 bar. As the pressure of the near-critical solution is isothermally decreased, these results indicate (1) an increase in the extent of asphaltene aggregation and/or; (2) increased attractive interactions among aggregates. Information derived from different regions of the X-ray scattering curve indicate increasing aggregation with decreasing pressure. From these experimental results, together with theoretical interpretation, we infer that as the pressure is reduced, increased aggregation of asphaltenes results which may contribute to formation damage in hydrocarbon reservoirs, and to fouling in hydrotreatment and cracking catalysts. 71 refs., 10 figs., 2 tabs.

• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5827303
• Journal Information: Langmuir; (United States), Vol. 9:8; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ASPHALTENES
AGGLOMERATION
CATALYSTS
CRITICAL PRESSURE
HYDROCRACKING
PENTANE
PETROLEUM
PRESSURE DEPENDENCE
RESERVOIR FLUIDS
RESERVOIR PRESSURE
SMALL ANGLE SCATTERING
SOLVENTS
X-RAY DIFFRACTION
ALKANES
ASPHALTS
BITUMENS
CHEMICAL REACTIONS
COHERENT SCATTERING
CRACKING
DECOMPOSITION
DIFFRACTION
ENERGY SOURCES
FLUIDS
FOSSIL FUELS
FUELS
HYDROCARBONS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
PYROLYSIS
SCATTERING
TAR
THERMOCHEMICAL PROCESSES
THERMODYNAMIC PROPERTIES
020400* - Petroleum- Processing
400201 - Chemical & Physicochemical Properties
020200 - Petroleum- Reserves
Geology
& Exploration