Vanadium and Nickel Distribution in Resin Fractions of High-Sulfur Heavy Oils

The mechanisms of occurrence and distribution of vanadium and nickel in resins and their fractions are studied with reference to high-sulfur heavy oils of Tatarstan, Samara Oblast (region), and Kazakhstan deposits. For all the investigated heavy oils, the content of vanadium and nickel in resins increase in direct proportion to the increase in contents of these metals in the oils. The resins were fractionated into benzene and alcohol-benzene fractions by adsorption chromatographic separation on silica gel. The alcohol-benzene fractions are characterized as being more polar on account of a larger content of oxygen-bearing structural groups. The special features of vanadium and nickel content and distribution in resin fractions are disclosed for heavy oils of various production complexes.