What are Fuel Ethers?

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are almost entirely used as blending components for gasoline, where their combination of high octane and oxygen content facilitate the preparation of high-peformance, cleaner burning fuels and biofuels.

Fuel ethers are clear, colourless to pale yellow liquid organic compounds with a distinctive turpentine-like odour. They contain oxygen in a chain of carbon and hydrogen atoms. Each oxygen atom is linked to two carbon atoms, forming a carbon-oxygen-carbon sequence. This is different to alcohols where each oxygen atom is linked to a carbon atom and a hydrogen atom, forming a carbon-oxygen-hydrogen sequence.

The biofuel Ethyl-tertiary-butyl-ether, or ETBE, is the most commonly used fuel ether in Europe, followed by methyl-tertiary-butyl-ether, or MTBE, then tertiary-amyl-methyl-ether, or TAME, and finally tertiary-amyl-ethyl-ether, or TAEE.

 

Molecular structures of Fuel Ethers 
ETBEMolecular structure of ETBE MTBEMolecular structure of MTBE

TAMEMolecular structure of TAME

 

TAEEMolecular structure of TAEE

Fuel ether properties: the key physical and chemical properties of MTBE, ETBE, TAME and TAEE

 Properties 

Conditions

Units

MTBE

ETBE

TAME

TAEE

 CAS Number

 

 

1634-04-4

637-92-3

994-05-8

919-94-8

 Molecular Wt.

 

g/mol

88.2

102.2

102.2

116.2

 Boiling Point

 

°C

55.3

73.1

86.3

101

 Oxygen Content

 

% wt.

18.2

15.7

15.7

13.8

 Research Octane Number

ISO5164

 

118

119

112

112

 Motor Octane Number

ISO5163

 

101

103

98

98

 Vapour Pressure

EN13016/1

kPa

55

28

17.2

6.9

 Water Solubility

20°C

g/l

42

16.4

11

4

 Log Pow

 

 

1.06

1.48

1.55

-

 Odour Detection in Water

 

µg/l

15

49

194

-

 Taste Detection in Water

 

µg/l

40

47

128

-

 Henry's Law Constant

25°C

Pa.m3/mol

53.5

166

111

-