Concentrations of vanadium and nickel and their ratio in heavy oil asphaltenes

Trends in the vanadium and nickel concentrations in asphaltenes of heavy oils from different oilfields, in which the total content of these metals vary from 0.0049 to 0.1795 wt %, have been studied. It has been shown that as the vanadium and nickel content in heavy oils increases, vanadium concentrates faster than nickel in asphaltenes. In heavy oils, asphaltenes contain approximately 40–90% of total vanadium and 25–75% of total nickel. The summed concentration of vanadium and nickel in heavy oil asphaltenes can reach 1 wt %.