Aromatics is the general terms of hydrocarbon which contains benzene ring structure. It’s important materials of organic chemical industry. There are single-ring aromatics and polycyclic aromatic hydrocarbon. Single-ring aromatics contains only one benzene ring, for example, benzene, toluene, ethylbenzene, xylene, cumene, dodecyl and so on. Polycyclic aromatic hydrocarbon is made up of two or more benzene ring that connected by single bond.