Alkenes, a significant class of unsaturated hydrocarbon, possess a carbon–carbon double bond. They can fall into two broad categories, namely, acyclic alkenes and cyclic alkynes. In accordance with the containing number of carbon–carbon double bond, alkenes can also be divided into several classes such as mono-enes, diene with one or two carbon–carbon double bond, respectively. Alkenes are manufactured industrially by hydrocarbon cracking. Raw materials are from intensively natural gas condensate components, which are broken apart to produce a mixture of primarily aliphatic alkenes and other products. The mixture is feedstock and temperature dependent, and subsequently separated by fractional distillation. This is mainly used for the production of small alkenes (up to six carbons).
