Molecular Structure:

Molecular Formula: C₆H₁₄O
Molecular Weight: 102.1748
IUPAC Name: 2-Ethoxy-2-methylpropane
Synonyms of Ethyl tert-butyl ether (CAS NO.637-92-3): tert-Butyl ethyl ether ; 2-Ethoxy-2-methylpropane
CAS NO: 637-92-3
Classification Code: TWA (5 ppm)
Melting point: −97 °C
EINECS: 211-309-7
RTECS: KN4730200
Density: 0.762 g/cm³
Boiling Point: 70 °C at 760 mmHg 
Index of Refraction: 1.387
Molar Refractivity: 31.55 cm³
Molar Volume: 133.9 cm³
Surface Tension: 20.6 dyne/cm
Enthalpy of Vaporization: 29.87 kJ/mol
Vapour Pressure: 143 mmHg at 25°C

  Ethyl tert-butyl ether (CAS NO.637-92-3) is commonly used as an oxygenate gasoline additive in the production of gasoline from crude oil.It offers equal or greater air quality benefits as ethanol, while being technically and logistically less challenging.

  Ethyl tert-butyl ether (CAS NO.637-92-3) is synthesized by mixing ethanol and isobutylene and reacting them with heat over a catalyst.

It produced by fermentation and distillation, is more expensive than methanol, which is derived from natural gas. Therefore, it made from methanol is cheaper than ETBE, made from ethanol. However, (bio)ethanol makes ETBE partially a biofuel, while it is entirely a fossil fuel and introduces a risk to the environment .

Reported in EPA TSCA Inventory.

Low toxicity by inhalation. When heated to decomposition it emits acrid smoke and irritating vapors.
Hazard Codes:
F: Flammable
Xn: Harmful
Risk Statements about Ethyl tert-butyl ether (CAS NO.637-92-3):
R 11 Highly flammable. 
R 19 May form explosive peroxides. 
R 20 Harmful by inhalation. 
R36/38 Irritating to eyes and skin. 
R52/53 Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment. 
R65 Harmful: may cause lung damage if swallowed.
Safety Statements:
S16 Keep away from sources of ignition - No smoking. 
S26 In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36/37/39 Wear suitable protective clothing, gloves and eye/face protection. 
S61 Avoid release to the environment. Refer to special instructions/safety data sheets. 
S62 If swallowed, do not induce vomiting: seek medical advice immediately and show this container or label. 
Attention:
1. Storage: Keep away from sources of ignition. Store in a cool, dry place. Store in a tightly closed container.
2. Handling: Use spark-proof tools and explosion proof equipment. Avoid breathing dust, vapor, mist, or gas. Avoid contact with skin and eyes. Avoid ingestion and inhalation.
3. Health Hazard: Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.

ACGIH TLV: TWA 5 ppm

 Unlike ethanol, Ethyl tert-butyl ether (CAS NO.637-92-3) does not induce evaporation of gasoline, which is one of the causes of smog, and does not absorb moisture from the atmosphere.