But-2-ene

It is a petrochemical, produced by the catalytic cracking of crude oil or the dimerization of ethylene.

Its main uses are in the production of high-octane gasoline (petrol) on alkylation units and butadiene,[4] although some but-2-ene is also used to produce the solvent butanone via hydration reaction to butan-2-ol followed by oxidation.

The two isomers are extremely difficult to separate by distillation because of the proximity of their boiling points (~4 °C for cis and ~1 °C for trans[5]).

However, separation is unnecessary in most industrial settings, as both isomers behave similarly in most of the desired reactions.

Butane and but-1-ene are common impurities, present at 1% or more in industrial mixtures, which also contain smaller amounts of isobutene, butadiene and butyne.

NFPA 704 four-colored diamond Health 1: Exposure would cause irritation but only minor residual injury. E.g. turpentine Flammability 4: Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Flash point below 23 °C (73 °F). E.g. propane Instability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogen Special hazards (white): no code