What is paraxylene and its properties?

Paraxylene, also called p-xylene, is an aromatic hydrocarbon usually derived from crude oil sources. The chemical formula of paraxylene is C6H4(CH3)2. For the manufacturing of polyester fabric and PET plastic bottles, it is one of the necessary raw materials. Paraxylene belongs to the family of xylenes which consists of the three isomers of dimethylbenzene. In 2018, more than 85% of the mixed xylene demand in the world was for paraxylene. By the process, catalytic reforming of petroleum naphtha BTX aromatics is produced which is benzene, toluene and the xylene isomers. p-Xylene is among one of them. To separate p-xylene from the other isomers and chemicals like m-xylene, o-xylene, and ethylbenzene, different reaction processes like distillation, adsorption or crystallization are performed.

The boiling and melting point of paraxylene is 138.35 °C and 13.2°C respectively. Paraxylene is colorless and is considered highly flammable in nature. Because of its flammable nature, this chemical needs special safety and care while handling. It is stored in an appropriate containment system in a cool and well-ventilated area, away from possible sources of ignition.

Harmful gases like carbon monoxide and carbon dioxide are produced by the thermal decomposition of this industrial chemical. Though it is considered to have a low toxicity level but exposure to high levels of p-xylene vapors can cause serious problems like drowsiness, dizziness, listlessness, confusion, irritability, gastrointestinal disturbances, etc. Skin and eye contact of this chemical can also cause dryness, redness, chest tightening, and irritation. Its inhalation can also cause problems like lung damage or chemical pneumonia.