Hydrogen Transfer of Petroleum Residue Subfractions During Thermal Processing under Hydrogen

Anthracene (ANT) was applied as the accepting probe to evaluate the hydrogen transfer ability of a Venezuela petroleum residue and its subfractions (i.e., saturates, aromatics, resins, and asphaltenes) under different atmospheres and reaction conditions. The hydrogen donating ability (HDA) of H-2, HDA of the fractions, and synergism between fractions and H-2 were analyzed. The results show that the temperature, initial hydrogen pressure, and time have a positive effect on the HDA of hydrogen. The HDA of all of the subfractions increases clearly with increasing temperature, both under nitrogen and hydrogen, before an equilibrium is achieved, and the HDA determined under hydrogen is higher than that measured under nitrogen. The saturates (Sa) and aromatics (Ar) showed a positive synergism with hydrogen, whereas the resins (Re) and asphaltenes (Asp) showed a negative one according to the calculated synergism. The summation HDA determined under nitrogen was significantly lower than the original HDA of the Venezuela petroleum residue, whereas the trend for hydrogen was the opposite.