CHARACTERIZATION OF ATHABASCA ASPHALTENES BY SMALL-ANGLE X-RAY-SCATTERING

Colloidal dispersions of Athabasca asphaltenes in toluene were studied at room temperature by small-angle X-ray scattering (SAXS). Both 5% a nd 15% dispersions were found to be polydispersed spheres with the mai n distribution peak at a concentration-independent average radius of 3 3 Angstrom. The main distribution peak was skewed to the right, simila r to a Schultz distribution. Owing to interparticle correlation, a sma ll proportion of the particles could be interpreted as forming larger aggregates, the size of which appeared to decrease on increasing the c oncentration of dispersion.