2,2,4-Trimethylpentane

Chemical compound other isomers of octane Octane#Isomers changed changed 477209668 2,2,4-Trimethylpentane.svg skin-invert-image correct ?? 160 Skeletal formula of 2,2,4-trimethylpentane Isooctane-3D-balls.png bg-transparent correct ?? 160 Ball and stick model of 2,2,4-trimethylpentane Isooctane-3D-vdW.png bg-transparent correct ?? 160 Spacefill model of 2,2,4-trimethylpentane 2,2,4-Trimethylpentane2,2,4-trimethylpentane - Compound Summary https://pubchem.ncbi.nlm.nih.gov/compound/10907 PubChem Compound National Center for Biotechnology Information 11 March 2012 USA 26 March 2005 Identification and Related Records 540-84-1 correct CAS correct FDA QAB8F5669O 10907 10445 correct chemspider 208-759-1 1262 2,2,4-trimethylpentane 62805 changed EBI 1797261 changed EBI SA3320000 1696876 CC(C)CC(C)(C)C 1S/C8H18/c1-7(2)6-8(3,4)5/h7H,6H2,1-5H3 correct chemspider NHTMVDHEPJAVLT-UHFFFAOYSA-N correct chemspider 8 18 Colorless liquid petroleum-like 0.692 g cm−3 165.77 372.45 4.373 5.5 kPa (at 21 °C) 3.0 nmol Pa−1 kg−1 210 nm 1.391 −98.34·10−6 cm3/mol −260.6 to −258.0 kJ mol−1 −5462.6 to −5460.0 kJ mol−1 328.03 J K−1 mol−1 242.49 J K−1 mol−1 flame exclamation mark health hazard environment DANGER 225 304 315 336 410 210 261 273 301+310 331 1 3 0 −12 396 1.1–6.0% alkanes 2,2-Dimethylbutane 2,3-Dimethylbutane Triptane Tetramethylbutane Tetraethylmethane 2,3,3-Trimethylpentane 2,3,4-Trimethylpentane Tetra-tert-butylmethane 2,3-Dimethylhexane 2,5-Dimethylhexane 2,2,4-Trimethylpentane, also known as isooctane or iso-octane, is an organic compound with the formula (CH3)3CCH2CH(CH3)2. It is one of several isomers of octane (C8H18). This particular isomer is the standard 100 point on the octane rating scale (the zero point is n-heptane). It is an important component of gasoline, frequently used in relatively large proportions (around 10%) to increase the knock resistance of fuel.Werner Dabelstein Arno Reglitzky Andrea Schütze Klaus Reders Automotive Fuels Ullmann's Encyclopedia of Industrial Chemistry 2007 Wiley-VCH Weinheim 10.1002/14356007.a16_719.pub2 978-3527306732 Richardson KA Wilmer JL Smith-Simpson D Skopek TR Assessment of the genotoxic potential of unleaded gasoline and 2,2,4-trimethylpentane in human lymphoblasts in vitro. Toxicology and Applied Pharmacology February 1986 82 2 316–22 10.1016/0041-008x(86)90207-3 3945956 1986ToxAP..82..316R Strictly speaking, if the standard meaning of "iso" is followed, the name isooctane should be reserved for the isomer 2-methylheptane. However, 2,2,4-trimethylpentane is by far the most important isomer of octane and historically it has been assigned this name.Clayden Jonathan Organic chemistry 2005 Oxford Univ. Press Oxford [u.a.] 978-0-19-850346-0 315 Reprinted (with corrections). registration https://archive.org/details/organicchemistry00clay_0/page/315 Production Isooctane is produced on a massive scale in the petroleum industry by alkylation of isobutene with isobutane. This process is conducted in alkylation units in the presence of acid catalysts.Alkylation Bipin V. Vora Joseph A. Kocal Paul T. Barger Robert J. Schmidt James A. Johnson 2003 Kirk-Othmer Encyclopedia of Chemical Technology 10.1002/0471238961.0112112508011313.a01.pub2 0471238961 thumb|class=skin-invert-image|left|400px|Route to 2,2,4-trimethylpentane from isobutene and isobutane It can also be produced from isobutylene by dimerization using an Amberlyst catalyst to produce a mixture of iso-octenes. Hydrogenation of this mixture produces 2,2,4-trimethylpentane.Dimerization of isobutylene, Amberlyst.com History Engine knocking is an unwanted process that can occur during high compression ratios in internal combustion engines. During the 1920s different measurement methods of knock were proposed but laboratories struggled to reproduce them reliably. In 1926 Ethyl Corporation's Graham Edgar selected two specific hydrocarbons, n-heptane (commercially available in high purity from Jeffrey pine) and 2,2,4-trimethylpentane, itself first synthesized from tert-butyl alcohol via diisobutene by J. W. McKinney at the same laboratory in the same year, as primary standards. Compared to various chemicals and natural gasolines proposed before that, these two compounds had extremely close boiling points, ensuring the vapor mixture in the cylinder would be the same regardless of the carburetor, and didn't depend on the composition of particular crudes.1927-01-01 Measurement of Knock Characteristics of Gasoline in Terms of a Standard Fuel1 https://pubs.acs.org/doi/pdf/10.1021/ie50205a049 2026-04-26 ACS Publications en 10.1021/ie50205a049 This method became known as the octane rating scale. Test motors using 2,2,4-trimethylpentane gave a certain performance that was standardized as 100 octane. The same test motors, run in the same fashion, using heptane, gave a performance which was standardized as 0 octane. All other fuels were then graded against mixtures of these two chemicals and assigned octane numbers.Brooks Donald B. 1946 Development of REFERENCE FUEL SCALES for KNOCK RATING https://www.jstor.org/stable/44548282 SAE Transactions 54 394–403 0096-736XFuels and lubricants handbook, Volume 1, George E. Totten, Steven R. Westbrook, Rajesh J. Shah, page 62 Safety In common with all hydrocarbons, 2,2,4-trimethylpentane is flammable.2,2,4-Trimethylpentane, Integrated Risk Information System, United States Environmental Protection Agency See also Oil refinery Antiknock agents References External links 2,2,4-Trimethylpentane International Chemical Safety Card 0496 Category:Alkanes Category:Antiknock agents