A dielectric relaxation study of precipitation and curing of Furrial crude oil

Abstract

Low frequency dielectric spectroscopy was applied to investigate the properties of Furrial crude oil that is infamous for asphaltene precipitation during production. An experiment was conducted at ambient temperature by mixing Furrial crude oil with hexane to induce flocculation and subsequent precipitation. A drastic change in dielectric response was observed near the critical point when flocculation occured. Evolution of the dielectric loss spectra as a function of time was observed and found to closely mimic epoxy-curing process. The curing process lasted for approximately 44 h with an induction period of at least 26 h. During the induction period, the conductivity contribution to the dielectric response remains dominant. Following the induction period a structural arrest occurs signaling the onset of deposition.