19F dynamic nuclear polarization and sem in suspensions consisting of fluorobenzene derivatives and asphaltene extracted from mc-800 liquid asphalt

Abstract

A variety of analytical techniques, such as scanning electron microscopy and F-19 dynamic nuclear polarization (DNP) methods, are applied to characterize asphaltene extracted from MC-800 liquid asphalt in fluorobenzene derivatives at 1.53mT and at room temperature. Different solvents show variable affinities for the asphaltene surface. The low field EPR spectrum of the asphaltene/hexafluorobenzene sample was recorded. The DNP parameters were determined. Additionally, the interactions between the nuclei of the solvent and the electrons delocalized on the asphaltene are interpreted. Not only dipolar but also scalar interactions between the nuclear spin and the electron spin were found.