Polyaromatic classification

PAH PAJ PAO PCBs Polyaromatic hydrocarbons. Petroleum Association of Japan. Poly-a-olefin base stock of various viscosity classifications. Any of the chlorinated derivatives of biphenyl (also called diphenyl). 

This statement corresponds to a new concept in classification of polyaromatic coke formed during catalytic reactions that provides a structural basis for the traditional classifications of hard coke and soft coke (d7-(5P). 

The hydrocarbons present in oil can be classified into four main classes saturated (alkanes and cycloparaffins), aromatics (hydrocarbons, mono, di and polyaromatic), resins (fractions consist of polar molecules containing heteroatoms such as N, O or S) and asphaltenes (they are molecules similar to the resins, but with a higher molecular weight and polyaromatic core). This classification is known as SARA (Wang et al, 2002 Speight, 2001 Tissot and Welt, 1978). 

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