Supramolecular Structures of Oil Systems as the Key to Regulation of Oil Behavior

Abstract

The paper is devoted to investigation of supramolecular structures formed by high-molecular components of oil -asphaltenes and waxes. Petroleum asphaltenes that are characterized by their ability to self-organization can be considered as a polydisperse system. The aggregation of A1and A2 asphaltenes both in toluene solution and in diluted heavy oils was studied by dynamic light scattering technique. The stabilizing role of resins was confirmed. Due to the fact that the supramolecular structures in oils can be also formed by high molecular microcrystalline waxes, their influence as well as A1 and A2 asphaltenes on wax crystallization process was evaluated using optical microscopy. The effect of the different molecular structures of asphaltenes (A1 and A2) on the rheological properties of crude oils was also observed. Self-organization of asphaltenes directly in heavy high-viscosity oils with high content of resins was investigated by varying the ratios oil:precipitant. It was shown that extremely stable supramolecular structures in heavy oils had been formed. The influence of ultrasonic action for the destruction of stable supramolecular structures and the reduction of oil viscosity were considered.Also petroleum asphaltenes can be the indicators of many processes that occur in the reservoir. We have shown the possibility of using the gradient of asphaltenes, as well as their structure, to confirm the influx of deep light hydrocarbons in carbonate reservoirs. Thus, all obtained results of investigation of structure formation processes will let regulate the macroscopic properties of heavy oils in the future and identify the processes occurring in the reservoir.