Names | |
---|---|
IUPAC name
2-Methoxy-2-methylpropane
|
|
Other names
Methyl tertiary-butyl ether; Methyl tert-butyl ether; Methyl t-butyl ether; MTBE; tert-Butyl methyl ether; tBME; tert-BuOMe
|
|
Identifiers | |
3D model (Jmol)
|
|
ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.015.140 |
KEGG | |
PubChem CID
|
|
|
|
|
|
Properties | |
C5H12O | |
Molar mass | 88.15 g·mol−1 |
Density | 0.7404 g/cm³ |
Melting point | −109 °C (−164 °F; 164 K) |
Boiling point | 55.2 °C (131.4 °F; 328.3 K) |
42 g/L (20 °C) | |
Viscosity | 0.36 cP at 25 °C |
Hazards | |
NFPA 704 | |
Flash point | −10 °C (14 °F; 263 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
|
what is ?) | (|
Infobox references | |
Methyl tert-butyl ether (also known as MTBE and tert-butyl methyl ether) is an organic compound with a structural formula (CH3)3COCH3. MTBE is a volatile, flammable, and colorless liquid that is sparingly soluble in water. It has a minty odor vaguely reminiscent of diethyl ether, leading to unpleasant taste and odor in water. MTBE is a gasoline additive, used as an oxygenate to raise the octane number. Its use is controversial because of its contamination of groundwater and legislation favoring ethanol. However, worldwide production of MTBE has been constant owing to growth in Asian markets.
MTBE is manufactured via the chemical reaction of methanol and isobutylene. Methanol is derived from natural gas, and isobutylene is derived from butane obtained from crude oil or natural gas, thus MTBE is derived from fossil fuels. In the United States, it was produced in very large quantities (more than 200,000 barrels (32,000 m3) per day in 1999) during its use as a fuel additive.
MTBE is used as a fuel component in fuel for gasoline engines. It is one of a group of chemicals commonly known as oxygenates because they raise the oxygen content of gasoline.
In the US it has been used in gasoline at low levels since 1979, replacing tetraethyl lead as an antiknock (octane rating) additive to prevent engine knocking. Oxygenates also help gasoline burn more completely, reducing tailpipe emissions from pre-1984 motor vehicles; dilute or displace gasoline components such as aromatics (e.g., benzene) and sulfur; and optimize oxidation during combustion. Before the introduction of other oxygenates and octane enhancers, most refiners had chosen MTBE primarily for its blending characteristics and low cost.