<Tr> <Td_colspan="2"> Infobox references </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> </Tr> <P> Methyl tert - butyl ether (also known as MTBE and tert - butyl methyl ether) is an organic compound with a structural formula (CH) COCH . 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 . </P> <P> 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 m) per day in 1999) during its use as a fuel additive . </P>

What is methyl tertiary butyl ether (mtbe)