The work deals with the study of the effect of the process of heavy oil etherification on the aggregative stability of asphaltenes and their structural changes. The etherification was carried out at various temperatures from 25 to 100°C for 8 h. It has been found that with an increasing temperature of oil treatment with isopropyl alcohol, an increase in the yield of resins and asphaltenes by 4 wt% is observed. Based on the data of IR-spectroscopy and NMR, it has been found that isopropyl radicals were likely to be incorporated into asphaltenes. In the structure of asphaltenes, aliphaticity, and branching increase by 3.5 and 2.9 times compared to the initial asphaltenes, respectively. Structural and group characteristics of asphaltenes were changed after the oil etherification, which was especially evident after the 100°C of process temperature. It was also found that the treatment of heavy oil with isopropyl alcohol practically does not affect the stability of asphaltenes.
