Applicability and structural relevance of Hansen solubility parameters for asphaltenes

Abstract

The Hansen solubility parameters of different asphaltenes were determined, and the combination of experimental and different characterization methods, such as the modified Brown-Lander method, X-ray diffraction, in situ infrared, dipole moment measurements, and X-ray photoelectron spectroscopy, confirmed that the Hansen solubility parameters can well reveal the strength of the interactions of asphaltenes, which are mixtures of condensed aromatic macromolecules, and indicated the applicability of using Hansen solubility parameters to study systems involving asphaltenes. By analyzing the relationship between the composition of asphaltenes and their interaction strengths, it was obtained that the strength of polar interaction is positively correlated with the condensation degree and the number of unit sheets; while the most influential factor on the strength of dispersion is the number of aromatic rings of asphaltenes; besides, the strength of hydrogen bond interaction increases with the heteroatomic content, while the different heteroatomic functional groups also have a great influence.