Petroleum treatment catalytic cracking

Solvent extraction may also be used to reduce asphaltenes and metals from heavy fractions and residues before using them in catalytic cracking. The organic solvent separates the resids into demetallized oil with lower metal and asphaltene content than the feed, and asphalt with high metal content. Figure 3-2 shows the IFP deasphalting process and Table 3-2 shows the analysis of feed before and after solvent treatment. Solvent extraction is used extensively in the petroleum refining industry. Each process uses its selective solvent, but, the basic principle is the same as above. 

Cat cracking Distillate fractions. Liquefied petroleum gas Catalytic treatment in... 

Pitch is a carbonaceous solid that consists primarily of a complex mixture of polycyclic aromatic compounds [14]. Petroleum pitches are residues of crude oil distillation or of catalytic cracking of petroleum distillates. Coal tar pitches are products of the distillation of coal, whereas synthetic pitches are residues of the treatment of other organic substances. Irrespective of origin, all pitch products have complex chemical compositions. 

Petroleum pitch can be obtained from a wide variety of sources such as from the bottoms of catalytic crackers, steam cracking of naphtha and gas oils, and residues from various distillation and refinery processes. The crude product is given an initial refining process, which can include one, or a combination of, several treatments ... 

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