Relation between Nanoscale Structure of Asphaltene Aggregates and their Macroscopic Solution Properties - IFPEN - IFP Energies nouvelles Access content directly
Journal Articles Oil & Gas Science and Technology - Revue d'IFP Energies nouvelles Year : 2009

Relation between Nanoscale Structure of Asphaltene Aggregates and their Macroscopic Solution Properties

Abstract

Some peculiar macroscopic properties of crude oils are ascribed to their densest, heaviest and most polar fraction: the asphaltenes. The comprehension of the origin of these properties relies on a fine structural description of these fractions. We present a nanometre length scale characterisation of asphaltene solutions based on new or recent scattering experiments (X-rays and neutrons) from which structural parameters of asphaltene aggregates (Mw, Rg and A2) are extracted. The mutual dependence of these parameters is consistent with a mass fractal model. This single model accounts for very different macroscopic solution properties. Solvent trapping in fractal aggregates enables asphaltene solution viscosity to be fully predicted as a function of asphaltene concentration. Asphaltene adsorbs at liquid-liquid and liquid-solid interfaces as a monolayer whose thickness is of the same order of magnitude as the characteristic size of the asphaltene aggregate in bulk. Adsorption isotherm analysis, neutron reflectivity experiments and contrast-matching SANS allow one to highlight a densification of the asphaltene aggregates in the adsorbed layer in comparison with the solvated aggregates in bulk. Finally, the repulsive/attractive interaction balance between aggregates can be related to the relative stability of water in oil emulsions and to the stability of hydro-conversion effluents. This structure/property approach allows one to assess the mass fractal model which is discussed.
Fichier principal
Vignette du fichier
ogst08123.pdf (795.94 Ko) Télécharger le fichier
Origin : Publication funded by an institution
Loading...

Dates and versions

hal-02001566 , version 1 (31-01-2019)

Identifiers

Cite

L. Barré, J. Jestin, A. Morisset, T. Palermo, Sunil Simon. Relation between Nanoscale Structure of Asphaltene Aggregates and their Macroscopic Solution Properties. Oil & Gas Science and Technology - Revue d'IFP Energies nouvelles, 2009, 64 (5), pp.617-628. ⟨10.2516/ogst/2009022⟩. ⟨hal-02001566⟩
39 View
179 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More