Editing Isomerization (section)

===Alkanes===
Skeletal isomerization occurs in the [[Cracking (chemistry)|cracking]] process, used in the [[petrochemical]] industry to convert straight chain alkanes to [[isoparaffin]]s as exemplified in the conversion of [[Octane|normal octane]] to [[2,5-Dimethylhexane|2,5-dimethylhexane]] (an "isoparaffin"):<ref name=Ullmann>{{cite book |doi=10.1002/14356007.a18_051 |chapter=Oil Refining |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2000 |last1=Irion |first1=Walther W. |last2=Neuwirth |first2=Otto S. |isbn=3-527-30673-0 }}</ref>
:[[File:Paraffintoisoparaffin.svg|center]]

Fuels containing branched [[hydrocarbon]]s are favored for internal combustion engines for their higher [[octane rating]].<ref>{{cite encyclopedia |author=Karl Griesbaum |author2=Arno Behr |author3=Dieter Biedenkapp |author4=Heinz-Werner Voges |author5=Dorothea Garbe |author6=Christian Paetz |author7=Gerd Collin |author8=Dieter Mayer |author9=Hartmut Höke |title=Hydrocarbons|encyclopedia=Ullmann's Encyclopedia of Industrial Chemistry|year=2002|publisher=Wiley-VCH|place=Weinheim|doi=10.1002/14356007.a13_227|isbn=3-527-30673-0 }}</ref>  Diesel engines however operate better with straight-chain hydrocarbons.