Editing Methyl tert-butyl ether (section)

===Alternatives to MTBE as an anti-knock agent===
Other oxygenates are available as additives for gasoline including [[alcohol fuel|ethanol]] and other ethers such as [[ETBE]].

Ethanol has been advertised as a safe alternative by agricultural and other interest groups in the U.S. and Europe. In 2003, California was the first U.S. state to start replacing MTBE with ethanol.

An alternative to ethanol is ETBE, which is manufactured from ethanol and isobutene. Its performance as an additive is similar to MTBE, but due to the higher price of ethanol compared to methanol, it is more expensive.

Higher quality gasoline is also an alternative, so that additives such as MTBE are unnecessary. [[Iso-octane]] itself is used. MTBE plants can be retrofitted to produce iso-octane from isobutylene.<ref name=nesteengineering>{{cite web |url=http://www.nesteengineering.com/default.asp?path=111,360,362,477 |title= NExOCTANE™ - Neste Jacobs |website=www.nesteengineering.com |archive-url=https://web.archive.org/web/20060106041047/http://www.nesteengineering.com/default.asp?path=111%2C360%2C362%2C477 |archive-date=January 6, 2006}}</ref><ref name=halliburton>{{Cite web |url=http://www.halliburton.com/kbr/hydroChem/petroChem/nexoctane.jsp |title=KBR - NExOCTANE™ |access-date=2006-01-31 |archive-url=https://web.archive.org/web/20060106003915/http://www.halliburton.com/kbr/hydroChem/petroChem/nexoctane.jsp |archive-date=2006-01-06 |url-status=dead }}</ref>