WHAT IS IT?
Methyl Tertiary Butyl Ether (MTBE) is an oxygenated organic compound (C₅H₁₂O) produced by reacting methanol with isobutylene. It is a colourless liquid with a distinctive odour, widely used as a high-octane gasoline blending component.
HOW IS IT MADE?
Methanol + Isobutylene → MTBE (via catalytic reaction)
Isobutylene comes from: FCC (Fluid Catalytic Cracking) units in refineries, or steam cracker C4 fractions.
KEY PROPERTIES
Research Octane Number (RON): 118 — very high octane booster
Blending RVP (Reid Vapour Pressure): Moderate
Oxygen content: 18.2% — helps combustion, reduces CO emissions
Water solubility: Slight but significant (environmental concern)
KEY USES
Gasoline blending (primary use) — boosts octane rating and reduces toxic aromatics (benzene, toluene)
Replacement for lead additives in fuel (after leaded gasoline phase-out)
WHY MTBE MATTERS
MTBE replaced tetraethyl lead (TEL) as the primary octane booster globally after leaded gasoline was banned. In markets where ethanol blending is not used (parts of Asia and Middle East), MTBE is the dominant octane booster.
CONTROVERSY
MTBE was banned in the USA after groundwater contamination incidents (MTBE leaks from underground storage tanks dissolve in groundwater, affecting drinking water taste at very low concentrations). Replaced by ethanol in the US market. Still widely used in Asia, Middle East, and Latin America.
TRADE CORRIDORS
Major producers: Saudi Arabia, China, South Korea, Malaysia
Major buyers: China, Southeast Asia, Latin America
Tetra relevance: South Korea and China are significant MTBE producers.
SPECIFICATIONS
Purity: min 98.0%
Methanol content: max 0.5%
Water: max 0.03%
Peroxide content: max 10 ppm
Specific gravity at 20°C: 0.744–0.746