Propyleen

Propyleen, also called propene or propylene, is a gaseous hydrocarbon with the formula C3H6. It is the simplest member of the alkene family that contains a carbon–carbon double bond. Propyleen is colorless, highly flammable, and has a faint, sweetish odor. At room temperature it is a gas, but it can be stored as a liquid under pressure or dissolved in solvents. Its boiling point is about -42 °C.

Propyleen is predominantly produced from petroleum refining and natural gas processing. It is generated during steam cracking of hydrocarbon feedstocks in refineries and petrochemical plants, and also occurs as a byproduct of catalytic reforming and fluid catalytic cracking. Global production volumes are large and fluctuate with refinery activity and demand for downstream products.

Major uses and derivatives: The largest share of propyleen is used as a feedstock for polypropylene production, which is polymerized using Ziegler–Natta or metallocene catalysts to yield a widely used plastic for packaging, textiles, automotive parts, and consumer goods. Other important derivatives include propylene oxide (for polyurethanes and glycols), cumene (leading to phenol and acetone), and acrylonitrile (for acrylic fibers and plastics). Hydroformylation of propyleen can produce butyraldehyde, an intermediate for plasticizers and resins.

Safety and handling: Propyleen is highly flammable and forms explosive mixtures with air. It can act as an asphyxiant at high concentrations and may cause health effects if inhaled. It is typically stored under pressure as a refrigerated liquid or in compressed gas cylinders, with appropriate controls to prevent leaks and ignition. Industry handling often includes inhibitors to prevent unwanted polymerization during processing.