Ethanol is commonly used as a biofuel and can be produced from plants containing sugar or starch, such as corn, sugarcane, or cellulosic crops. It is made through the fermentation of sugars with yeast and is the same type of alcohol found in alcoholic drinks. Ethanol provides advantages as a fuel in that it is renewable, produces fewer greenhouse gas emissions than gasoline, and burns more cleanly. However, ethanol also has some disadvantages like a lower energy content than gasoline and production requiring significant land and water resources.

1. ETHANOL
The Bio Fuel
By
K. Jayaram
II
ECE –A

2. ETHYL ALCOHOL (or)
ETHANOL
 Ethanol fuel is ethyl alcohol, the same type of
alcohol found in alcoholic beverages, used as fuel.
 It is most often used as a motor fuel, mainly as a
biofuel additive for gasoline.
 It is commonly made from biomass such as corn or
sugarcane.

3. Structure of Ethyl-
Alcohol

4. Bioethanol is a form of quasi-renewable energy that can be
produced from agricultural feed stocks.
It can be made from very common crops such as hemp, sugarcane,
potato, cassava and corn.
Cellulosic ethanol offers promise because cellulose fibers,
a major and universal component in plant cells walls, can be used to
produce ethanol.
MAJOR SOURCES

5. Ethanol Production
During ethanol fermentation, glucose and
other sugars in the corn (or sugarcane or
other crops) are converted into ethanol and
carbon dioxide.
C6H12O6 → 2 C2H5OH+ 2 CO2 + heat

6. Ethanol Production
Ethanol may also be produced industrially
from ethylene
by hydration of the double bond in the
presence of catalysts and high temperature.
C2H4 + H2O → C2H5OH

7. PRODUCTION PROCESS

8. Ethanol plant in Turner County, South Dakota

10. • various mixture of bioethanol with gasoline or
diesel fuels have been used. The most well‐known
blends are :
E5G to E26G (5‐26% ethanol, 95‐74% gasoline)
E85G (85% ethanol, 15% gasoline
E15D (15% ethanol, 85% diesel)
E95D (95% ethanol, 5% water )

11. ADVANTAGES

12.  ADVANTAGES
• Ethanol‐blended fuel as E10 (10% ethanol and
90% gasoline) reduces greenhouse gases by up
to 3.9%.
• Ethanol is considered a renewable energy
resource because it is primarily the result of
conversion of the sun's energy into usable
energy
• It reduces greenhouse gases.
• It reduces the amount of high‐octane additives.
• The fuel spills are more easily biodegraded or
diluted to non toxic concentrations

13. • Exhaust gases of ethanol are much cleaner , it
burns more cleanly (more complete combustion)
• The use of ethanol‐blended fuels such as E85 (85%
ethanol and 15% gasoline) can reduce the net
emissions of greenhouse gases by as much as
37.1%, which is a significant amount.
• You can use any plant for production of bioethanol,
it only has to contain sugar and starch. The best
choice is sugar cane, but you can also use potatoes,
barley , wheat etc.
• It is carbon neutral i.e. the carbon dioxide released
in the bioethanol production process is the same
amount as the one the crops previously absorbed
during photosynthesis

14. DISADVATAGES

15. The energy content of the petrol is much higher
than the one of bioethanol. Burning 1 litre of
ethanol gives 34% less energy than burning the
same amount of petrol
phosphorous and nitrogen used in the production
have negative effect on the environment
During the production process of bioethanol a
huge amount of carbon dioxide is released.
The production of ethanol fills the air with
greenhouse gases (GHG) in the amounts
comparable to the emissions of
internal‐combustion engines
 DISADVANTAGES

16. Transportation – ethanol is hygroscopic, it
means that it absorbs water from the air and
thus has high corrosion aggressiveness.
Biodiversity – A large amount of arable land is
required to grow crops. This could see some natural
habitats destroyed including rainforests.
The food V fuel debate – There is concern that
due to the lucrative prices of bioethanol some
farmers may sacrifice food crops for biofuel
production which will increase food prices around
the world.

17. Comparison of Gasoline and Bioethanol

18. •Energy content
• Bioethanol has much lower energy content than
gasoline (about two‐third of the energy content of
gasoline )
•Octane number
• Octane number of ethanol is higher than that for
petrol; hence ethanol has better antiknock
characteristics.
• This increases the fuel efficiency of the engine. The
oxygen content of ethanol also leads to a higher
efficiency , which results in a cleaner combustion
process at relatively low temperatures.

19. • Reid vapour pressure (measure for the volatility of
a fuel)
• Very low for ethanol indicates a slow evaporation,
which has the advantage that the concentration of
evaporative emissions in the air remains relatively low .
• This reduces the risk of explosions. However , the low
vapour pressure of ethanol, together with its single
boiling point, is disadvantageous with regard to engine
start at low ambient temperatures.
• Without aids, engines using ethanol cannot be started
at temperatures below 20ºC. Cold start difficulties are
the most important problem with regard to the
application of alcohols as automotive fuels.

20. Application of ethanol
• Ethanol can be used :
• as a transport fuel to replace gasoline
• as a fuel for power generation by thermal
combustion
• as a fuel for fuel cells by thermochemical
reaction
• as a fuel in cogeneration systems
• as a feedstock in the chemicals industry