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A flammable liquid hydrocarbon, C8H18, having a highly branched structure and used as a solvent and to determine the octane ratings of fuels.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Chemistry) a colourless liquid alkane hydrocarbon produced from petroleum and used in standardizing petrol. Formula: (CH3)3CCH2CH(CH3)2. See also octane number
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌaɪ soʊˈɒk teɪn)

the octane isomer used as one of the standards in fixing the octane number of a fuel.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Isobutene on alkylation with butane produces isooctane, which is extensively used as a fuel additive in aviation fuel.
In addition, Gevo also signed a memorandum of understanding, or MOU, with Praj Industries to commercialize Gevo's renewable hydrocarbons products in India, including Gevo's renewable alcohol-to-jet fuel and renewable isooctane, derived from Gevo's renewable isobutanol.
The following pro analyse (P.A.) grade reagents were used: Sodium chloride (Cromoline[R] Quimica Fina--Brazil); Suprapur[R] nitric acid 60% (by mass), chloroform, hexane, methanol (Merck Millipore[R]--Germany); isooctane, glacial acetic acid, sulfuric acid, soluble starch, potassium iodate, sodium carbonate, potassium hydroxide, p-anisidine, sodium thiosulfate, potassium iodide, methyl tricosanoate (C23:0) 99,0% (by mass), boron trifluoride-methanol solution ([BF.sub.3]) 14% (m/V) in methanol, fatty acids methyl ester Supelco[R] 37 Component FAME Mix standard (10 mg/mL in methylene chloride), docosahexaenoic acid methyl ester (10 mg/mL in heptane), eicosapentaenoic acid methyl ester (10 mg/mL in heptane) and mercury standard (1000 [micro]g/mL Hg in 10% HN[O.sub.3]) (Sigma-Aldrich[R]-USA).
Isooctane or hexane, Anhydrous sodium sulfate: store at 100[degrees]C N-EVAP model 112 nitrogen evaporator (Organomation) with moisture trap in line from N2 source (Fig.
Isooctane (1 mL) and 6% potassium carbonate (8 mL) were added the mixture and centrifuged for 10 minutes at 1,500xg.
The upper phase (isooctane and methyl esters of fatty acids) was transferred to flakes with 5ml capacity, sealed tightly and stored at -18[degrees]C under N2 for chromatographic analysis.
[15] in an inverse AM polymerization using isooctane as the continuous phase and an oil-soluble azo initiator, claimed with a model based on Monte Carlo approach that the kinetics resemble the classical emulsion Case-2 kinetics, where the average radical number is 0.5.
4-methylimidazole (4-MeI), 2-ethylimidazole (2-EI), bis(2-ethylhexyl) phosphoric acid (BEHPA), isobutyl chloroformate (IBCF), hydrochloric acid, isooctane, and pyridine were obtained from Sigma-Aldrich, Poznan, Poland.
Andreu, "High precision measurement of silicon in naphthas by ICP-OES using isooctane as diluent," Talanta, vol.