propilena

Propilena, also known as propylene or propene, is the simplest alkene with the formula C3H6. Its structure features a carbon–carbon double bond (CH2=CH−CH3) and a terminal methyl group. Propilena is a colorless, flammable gas at room temperature and standard pressure, and it is a major feedstock in the petrochemical industry.

Commercially, propilena is produced mainly by steam cracking of larger hydrocarbon feedstocks such as propane, naphtha, or gas oils, and it is often recovered as a byproduct of refining. It is separated from other products by distillation and purification steps. Given its large-scale production, propilena is commonly shipped and stored as a compressed gas or low-boiling liquid.

The primary use of propilena is as a precursor to polypropylene via polymerization, typically with Ziegler–Natta or metallocene catalysts. It is also a starting material for other chemicals, including propylene oxide, acrylonitrile (via ammoxidation), cumene for phenol and acetone, and various propylated derivatives used in coatings and adhesives.

Chemical properties include its reactivity across the C=C bond, enabling hydrogenation to propane, hydrohalogenation, and halogenation. Propilena is stored with inhibitors to prevent unwanted polymerization and kept away from heat, sparks, and flames due to flammability and potential pressure buildup.