What is METHYL TERTIARY BUTYL ETHER (MTBE)?

METHYL TERTIARY BUTYL ETHER (MTBE) — an ether manufactured by reacting methanol and isobutylene. The resulting ether has a high octane and low volatility. MTBE is a fuel oxygenate and is permitted in unleaded gasoline up to a level of 15 percent. It is one of the primary ingredients in reformulated gasolines.