Naphthenes


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Related to Naphthenes: Naphthalenes

Naphthenes

 

alicyclic alkanes primarily found in petroleum (hence their name, which was first introduced in organic chemistry in 1883 by V. V. Markovnikov and V. N. Ogloblin). The most important naphthenes are cyclopentane and cyclohexane and their alkyl derivatives. Hydrocarbons containing several five- and six-member rings (including condensed forms such as Decalin) are also classified as naphthenes. However, some authors incorrectly expand the class to cover all cycloalkanes (cyclanes).

References in periodicals archive ?
Summary: Two new monocyclic naphthene derivatives (1and 2) along with seven known compounds for the first time from the chloroform soluble fraction of the Tamarix indica.
Fuel Type RQ (= C[O.sub.2]/ Range of RQ [O.sub.2,st]) relation Paraffins, 1/{1 + (1/2 + 1/2h)} 1/2 < RQ < (2/3) [C.sub.n] [H.sub.2n+2] Diolefins, 1/{1 + (1/2 - 1/2n)} 2/3 < RQ < (4/5) [C.sub.n] n [greater than or equal to] 2 [H.sub.2n+2] Aromatics, 1/{(3/2 - 3/2n)}, 2/3 < RQ < (4/5) [C.sub.n] n [greater than or equal to] 6 [H.sub.2n-6] Olefins, (2/3) (2/3) * naphthenes, or cycloparaffin, [C.sub.n] [H.sub.2n] Alcohols, (2/3) (2/3) * [C.sub.n] [Th.sub.2n+2]O Fuel Type Remarks Paraffins, RQ increases slightly with "n"; RQ = 1/2 for [C.sub.n] C[H.sub.4], RQ incresaes with n and RQ [right [H.sub.2n+2] arrow] (2/3) as n [right arrow] [infinity].
[degrees]c ASTM D 86 / EN ISO 3405 Final boiling point [degrees]c ASTM D 86 / EN ISO 3405 Total aromatics % v/v ASTM D 6839 / EN ISO 22854 Total olefmes % v/v ASTM D 6839 / EN ISO 22854 Aromatics C10 % v/v ASTM D 6839 / EN ISO 22854 Aromatics >C10 % v/v ASTM D 6839 / EN ISO 22854 Naphthenes C10 % v/v ASTM D 6839 / EN ISO 22854 Paraffins >C11 % v/v ASTM D 6839 / EN ISO 22854 High boilings ([alpha]-Methyl- Naphthalene to n-C26) % v/v VDA 265 Table 2.
Naphthene is used to describe the group of cycloalkanes.
According to George, V and Dyroff, the composition of crude oil varies with the locality of occurrence, but all contains alkanes (straight and branched chain from about (C1-C40), cycloalkares or naphthenes and aromatic hydrocarbons.
These pyrolytic products can be divided into a gas fraction, a liquid fraction consisting of paraffins, olefins, naphthenes and aromatics (PONA), and solid residues [14].
Paraffins and Naphthenes. The normal and branched alkanes are located at the bottom of the 2D plane, and branched alkanes tend to occupy the lower part with the number of carbon atom increasing.
Significant reductions in concentration of naphthenes and aromatics components of the crude oil as shown in the GC fingerprints indicates the catabolic versatility of the two Pseudomonas isolates.
(alkanes, naphthenes, alkynes, aromatics, and others), from viscously
Hydrotreatment is a process that converts polycyclic aromatics into naphthenes and allows for production of environmentally-sound naphthenic oils without production of carcinogenic side products.
The limitation arises due to the presence of ring compounds (aromatics and naphthenes), the concentrations of which do not change considerably during the upgrading process.