olefinas

Olefinas, commonly known as olefins or alkenes, are hydrocarbons defined by the presence of at least one carbon–carbon double bond. For acyclic mono-olefins, the general formula is CnH2n; the simplest members are ethene (ethylene) and propene (propylene). The term olefin derives from historical naming of ethene as “olefiant gas.” Olefins are unsaturated and typically nonpolar.

Molecularly, olefins can be linear (1-alkenes), branched, or cyclic. The double bond imparts higher reactivity than alkanes, enabling various addition reactions such as hydrogenation, halogenation, hydrohalogenation, and hydration. They can also undergo polymerization to form plastics and other polymers. In practice, industrial olefins range from small gases to heavier liquids and are common starting materials in petrochemical synthesis.

Industrial production and sources: most olefins are derived from petroleum and natural gas liquids. They are produced mainly by steam cracking or catalytic cracking of larger hydrocarbons, followed by separation and purification. Ethene, propene, and butenes are especially important feedstocks in the petrochemical industry.

Uses and applications: olefins are primarily used as monomers to produce polyolefins, with polyethylene from ethene and polypropylene from propene accounting for a large share of plastics production. They also serve as intermediates for a wide range of chemicals, including alcohols, glycols, and various specialty products. Olefins are also employed as solvents and in manufacturing processes across chemical industries.

Safety and environmental aspects: olefins are typically flammable and can be irritants. Their handling requires proper safety measures, and their production and use raise considerations related to emissions, energy use, and plastic waste management.