ABSTRACT
Nowadays, the rening processes are focused on the conversion of heavy crude oils and residua as the consequence of the increasing demand to produce more gasoline and middle distillates and the decreasing production of light crude oils. Heavy fractions of petroleum can be dened as those molecules, which have more than 25 carbon atoms distributed in asphaltenes and resins, along with high boiling points (Merdrignac and Espinat, 2007).
