iso-Octane is a branched hydrocarbon from the alkane group with the chemical formula C8H18. It is the most important of the eighteen octane isomers. Since it is an important component of motor gasoline, it is produced synthetically, but is also found to a small extent in petroleum.
|
Parameter |
Unit |
|
|
CAS Number |
540-84-1 |
|
|
EC Number |
208-759-1 |
|
|
Customs tariff number |
29011000 |
|
|
Molar Mass |
g/mol |
114.23 |
|
State at ambient temperature |
liquid, colourless |
|
|
Odour |
gasoline |
|
|
Density |
g/cm3 (15 °C) |
0.69 |
|
Melting Point |
°C |
-107 |
|
Boiling Point |
°C |
99 |
|
Flash Point |
°C |
-12 |
|
Vapour Pressure |
kPa (20 °C) |
5.31 |
|
Refractive Index |
1.3884 |
iso-Octane is almost insoluble in water, but shows very good solubility or unlimited miscibility with many organic solvents such as ethanol, ethers, esters, white spirit, benzene or chlorinated hydrocarbons. The RON (Research Octane Number) of iso-octane is by definition = 100.
Like all alkanes (paraffins, unsaturated hydrocarbons), iso-Octane is a very good solvent for nonpolar substances, fats and oils. Especially in the pharmaceutical industry it is used as an inert solvent, for purification, recrystallization and washing of active pharmaceutical substances.
Heavy greases or oils can be diluted with paraffins such as iso-octane to facilitate application. It is also found as an ingredient in paints, varnishes and adhesives. Aromatics-free thinner for paints consists largely of iso-octane.
iso-Octane has an octane number of 100, which has been defined internationally. This makes high-purity iso-octane (min. 99.75 %) a primary reference fuel for determining the octane number of a gasoline in a specially built engine. Since the demand for iso-octane is much greater than it can be obtained from petroleum, it is produced by the alkylate process from isobutene and isobutane.
Synonyms: Iso-Octane, isooctane, 2,2,4-Trimethylpentane