Main-Product

Methyl tert‐butyl ether (MTBE) is a tertiary alkyl ether with the chemical formula C₅H₁₂O. It is a clear, colorless, volatile liquid with a characteristic terpene-like odor, used primarily as a high-octane gasoline oxygenate and as a solvent in chemical processes.

MTBE is manufactured by the acid‐catalyzed etherification of isobutylene with methanol over a sulfonated polystyrene–divinylbenzene ion-exchange resin (e.g., Amberlyst 15). 

MTBE serves as:

• Gasoline Oxygenate and Octane Booster
  Raises octane rating, reduces engine knock, and supplies oxygen to improve combustion, thereby lowering carbon monoxide, VOCs, and particulate emissions.
• Solvent and Chemical Intermediate
  Used in pharmaceuticals and coatings as a polar aprotic solvent and as a precursor for high-purity isobutylene production.

Although MTBE effectively reduces tailpipe pollutants, its high water solubility and mobility have led to groundwater contamination issues, prompting regulatory restrictions in several jurisdictions such as in the United States, where MTBE usage peaked at ~260,000 barrels/day in 1999, then declined due to liability issues.

Global MTBE production capacity was estimated to be 35 million t/yr in 2018, with major producers in Asia and the Middle East.; current U.S. production is minimal, primarily for export. 

References

1. Methyl tert-butyl ether - Wikipedia
2. Methyl t-Butyl Ether (MTBE) Technical Product Information - Monument Chemical
3. MTBE (Methyl Tert-Butyl Ether) - Evonik
4. Methyl tertiary butyl ether (mtbe) - Chemistry and Behavior - United States Environmental Protection Agency (EPA)

Liquid