Impedance response of asphaltene solutions: Effect of solvation

Abstract

The present work uses a combination of X-ray diffraction (XRD) analysis and dielectric spectroscopy (DES) to study asphaltene aggregation and interactions between these aggregate and maltene phases, with the variations in solvency power of the maltenes, at different asphaltene concentrations. The ability of the dielectric spectroscopy to quantify the interaction of the asphaltenes with the maltene phase lead to the development of a correlation with respect to the solution viscosity.It was seen that the combination of the data obtained from the XRD and DES accounted for differing asphaltene molecular structures, variations in the maltene phase with respect to its solvency power as well as the asphaltene concentration in the solution. This is the first step in developing the ability to predict solution viscosity, as well as eventually explaining rheological behavior, of asphaltene containing compositions.The future application of this work will be to assess if the findings of the methodology used in this paper,i.e. the combination of DES and XRD to predict asphaltene aggregation behavior and solvation, is applicable for asphaltenes from crude oils and heavy oil sands. In addition the use of the DES technique for online insitu monitoring of viscosity of crude oils/ refinery bitumen formulations will also be explored.