Editing Naphtha (section)

==Types==
Various qualifiers have been added to the term "naphtha" by different sources in an effort to make it more specific:

One source<ref>{{cite conference  | first = Rune  | last = Prestvic  |author2=Kjell Moljord |author3=Knut Grande |author4=Anders Holmen   | title = Compositional analysis of naphtha and reformate  | book-title = Catalytic naphtha reforming  | pages = 2  | publisher = CRC Press  | year = 2004  | location = USA  | isbn = 9780203913505 | url = https://books.google.com/books?id=Bjs7d2xnm1UC&pg=PA60  | access-date = 2010-02-03}}</ref> distinguishes by boiling point:
{{blockquote|''Light naphtha'' is the fraction boiling between 30&nbsp;°C and 90&nbsp;°C and consists of molecules with 5–6 carbon atoms. ''Heavy naphtha'' boils between 90&nbsp;°C and 200&nbsp;°C and consists of molecules with 6–12 carbon atoms.}}

Another source<ref>"Chemistry of Hazardous Materials, Third Edition", Meyer, E., Prentice Hall, 1998, page 458.</ref> which differentiates ''light'' and ''heavy'' comments on the hydrocarbon structure, but offers a less precise dividing line:
{{blockquote|''Light'' [is] a mixture consisting mainly of straight-chained and cyclic aliphatic hydrocarbons having from five to six carbon atoms per molecule. ''Heavy'' [is] a mixture consisting mainly of straight-chained and cyclic aliphatic hydrocarbons having from seven to nine carbon atoms per molecule.}}

Both of these are useful definitions, but they are incompatible with one another and the latter does not provide for mixes containing both six and seven carbon atoms per molecule. These terms are also sufficiently broad that they are not widely useful.

"Petroleum naphtha", which contains both heavy and light naphtha, typically constitutes 15-30% of crude oil by weight.<ref name = "naphtha engines"/>