44
Alternative Fuels for Transportation
nitrogen oxides emissions depending on engine family and testing
procedures.
4. Biodiesel has about 11% oxygen by weight and no sulfur. The use
of biodiesel can extend the life of diesel engines because it is more
lubricating than petroleum diesel fuel, while fuel consumption, auto
ignition, power output, and engine torque are relatively unaffected
by biodiesel.
5. Biodiesel is safe to handle and transport because it is biodegradable
as sugar, 10 times less toxic than table salt, and has a high flashpoint
about 110°C compared to petroleum diesel fuel whose flash point is
45–55°C).
6. Biodiesel can be made from domestically produced, renewable oil
seed crops such as soybeans, jatropha, cottonseed, rubber seed, and
mustard seed.
3.2 Biodiesel Production
Vegetable oil reacts with alcohol (typically methanol or ethanol) in the presence of catalyst produced biodiesel. Biodiesel production process consists of
three steps; namely,
1. Conversion of triglycerides (TG) to diglycerides and one ester
molecule
2. Followed by the conversion of diglycerides (DG) into monoglycerides (MG) and one ester molecule
3. Monoglycerides into glycerol and one ester molecule
catalyst
Triglycerides T
( G) + R ′OH ⇔ Diglycerides ( ( DG) + R C
′ OOR 1
catalyst
Diglycerides (TG ) + R O
′ H ⇔ M Monoglycerides ( MG) + ′
R COOR 2
catalyst
Monoglycerides ( MG G) + R ′OH ⇔ Glycerol + R C
′ OOR .
3
Glycerol, the by-product of the transesterification process, also has commercial value. Stoichiometrically, three moles of alcohol are required for each
mole of triglyceride, but in general, a higher molar ratio is often employed
for maximum ester production and moves the reaction toward the forward
direction. It also depends upon the type of feedstock, amount of catalyst,
temperature, and so on. Commonly used alcohols include methanol, ethanol,
Alternative Fuels for Transportation
nitrogen oxides emissions depending on engine family and testing
procedures.
4. Biodiesel has about 11% oxygen by weight and no sulfur. The use
of biodiesel can extend the life of diesel engines because it is more
lubricating than petroleum diesel fuel, while fuel consumption, auto
ignition, power output, and engine torque are relatively unaffected
by biodiesel.
5. Biodiesel is safe to handle and transport because it is biodegradable
as sugar, 10 times less toxic than table salt, and has a high flashpoint
about 110°C compared to petroleum diesel fuel whose flash point is
45–55°C).
6. Biodiesel can be made from domestically produced, renewable oil
seed crops such as soybeans, jatropha, cottonseed, rubber seed, and
mustard seed.
3.2 Biodiesel Production
Vegetable oil reacts with alcohol (typically methanol or ethanol) in the presence of catalyst produced biodiesel. Biodiesel production process consists of
three steps; namely,
1. Conversion of triglycerides (TG) to diglycerides and one ester
molecule
2. Followed by the conversion of diglycerides (DG) into monoglycerides (MG) and one ester molecule
3. Monoglycerides into glycerol and one ester molecule
catalyst
Triglycerides T
( G) + R ′OH ⇔ Diglycerides ( ( DG) + R C
′ OOR 1
catalyst
Diglycerides (TG ) + R O
′ H ⇔ M Monoglycerides ( MG) + ′
R COOR 2
catalyst
Monoglycerides ( MG G) + R ′OH ⇔ Glycerol + R C
′ OOR .
3
Glycerol, the by-product of the transesterification process, also has commercial value. Stoichiometrically, three moles of alcohol are required for each
mole of triglyceride, but in general, a higher molar ratio is often employed
for maximum ester production and moves the reaction toward the forward
direction. It also depends upon the type of feedstock, amount of catalyst,
temperature, and so on. Commonly used alcohols include methanol, ethanol,