ABSTRACT
The complex and heaviest part of petroleum is the asphaltene, which is, in large amount, in heavy or extra heavy crude oils. The asphaltene has been dened rst by the French scientist J. B. Boussingault (1837) when he published his celebrated journal on the Composition of Bitumen in the year 1837. Later, in 1859, crude oil had been treated more extensively in Pennsylvania in order to distillate and discover commercial applicability of different fractions. Since then reners and technology developers have been working to gure out what to do with the rest of the barrel. The importance of crude oil began in the late 1990s, when the price of bottom of barrel increased due to the decline in the light feedstock. Since that time, steady progress was made over the past several years. The crude oil processing generally starts with desalting and, subsequently, atmospheric and vacuum distillations; after that, due to the large amount of bottom of barrel, atmospheric residue (AR) and/or vacuum residue (VR) are converted into lighter fractions with hydrogen addition (catalytic) or carbon rejection (thermal) processes. Direct hydroprocessing of heavy crude oils to produce upgraded oil has also been recently proposed (Ancheyta and Rana, 2008c).
