Octane (redirected from C8h18)

octane

a liquid alkane hydrocarbon found in petroleum and existing in 18 isomeric forms, esp the isomer n-octane. Formula: C₈H₁₈

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Octane 

n-octane, a saturated hydrocarbon, C₆H₁₈; a colorless liquid with a characteristic odor. Melting point, –56.8°C; boiling point, 125.67°C; density, 0.7025 g/cm³ at 20°C; octane number, 17–19. Along with isooctane and other isomers, octane is found in petroleum and straight-run gasoline (up to 10 percent); large quantities of octane are present in synthetic gasoline prepared from CO and H₂.

Octane is extracted commercially by rectification, then refined with urea or by means of molecular sieves. At 500°C and a pressure of 1–2 meganewtons per sq m, or 10–20 kilograms-force per sq cm, octane converts into a mixture of aromatic hydrocarbons (o-xylene and ethylbenzene) when passed over an aluminum-molybdenum or aluminum-chromium catalyst in the presence of hydrogen. This dehydrocyclization reaction is one of the main processes used in catalytic reforming.