Asphaltene macrostructure by small angle neutron scattering

Abstract Small angle neutron scattering has been used for studying the asphaltene macrostructure in liquid dispersions. Thanks to modelling calculations, the experimental data have been interpreted in terms of flat particles or sheets with a diameter in the range (6–20 nm) and a mean thickness of about 0.6–0.8 nm. In tetrahydrofuran, there is a slight concentration effect on this macrostructure. On the other hand, the mean aggregate size is very solvent dependent. Similar shapes and sizes have been found for different asphaltenes extracted from various crude oils. The fact that catalytic hydrotreatment dramatically reduces the mean size of the asphaltenes has also been verified.