Methyl tert-butyl ether (English name: methyl tert-butyl ether, abbreviated MTBE) is an organic compound with a chemical formula of C5H12O, a molecular weight of 88.15, an appearance of a colorless liquid, a relative density of 0.7405, and a boiling point of 55.2°C. Soluble in ethanol and ether, slightly soluble in water. It is derived from the reaction of isobutylene and methanol under the catalysis of ion exchange resin. It is a high-octane gasoline additive. It is often used as a gasoline additive to improve the cold start characteristics, acceleration performance and octane number distribution of gasoline.