alternative liquid fuels , ethanol and methanol production , application of ethanol and methanol , limitations and conclusion, contains all production of ethanol and methanol all over the world chart.
2. I N T R O D U C T I O N
BIOFUEL : Biofuel, any fuel that is derived from biomass-that is, plant or algae material or animal waste.
Since such feedstock material can be replenished readily.
• “Biomass fuel" is used over 85 % of rural households and in 15% urban dwellings. Agriculture
products rich starch and wheat, maize, sugarcane can be fermented to produce Ethanol (C₂H5OH),
Methanol (CH3OH).
• This can be produced by distillation of biomass the contains cellulose, wood and bagasse.
• Biofuels can be solid, gaseous or liquid, even though the term is often used in the literature in a
narrow sense to refer only to liquid biofuels for transport.
• These produced fuels are also called as Alternative fuels.
biofuel is considered to be a source
of renewable energy,
3. A LT E R N AT I V E F U E L S
• Alternative fuels are the liquids used instead of the fossil fuels in the vehicles
to run motors.
• The main use of the alternative fuel is to reduce the dependent on the fossil
fuels and to reduce the concentration of carbon dioxide in the atmosphere.
• The source of 1G – the first generation of biofuels – include edible sources like
molasses, sugar-containing materials like sugarcane, sugar beet and
sorghum, starch-containing materials like corn, cassava and rotten potatoes,
and edible oil seeds. 2G biofuels use non-edible sources like non-edible
oilseeds (e.g. Jatropha curcas), used cooking oil, agriculture residue such as
rice straw, cotton stalk, corn cobs, saw dust, bagasse, etc. 3G biofuels are
drawn from industrial waste, municipal solid waste, etc.
4. Non-petroleum liquid fuels find use when petroleum fuels are scarce or costly.
Methanol (CH3OH), Ethanol (C2H5OH) and Biodiesel are used as fuels in I.C. engines.
• Ethanol (or ethyl alcohol) can be produced by "fermentation of carbohydrates“ which
occur naturally and abundantly in some plants like sugarcane and starchy materials
like corn and potatoes.
• Methanol can be produced from municipal solid wastes and specially grown biomass.
• Biodiesel is produced from non-edible oil seeds.
• Producer gas is obtained by partial combustion of wood or any cellulose organic
material of plant origin.
PRODUCTION OF BIOFUELS
5. E T H A N O L
Ethanol (C2H5OH) is obtained commercially by fermentation, the oldest method is from sugars.
The sugar in molasses, sugarcane or fruits such as grapes is converted to glucose and
fructose, (both of which have the formula C6H12,O6), in the presence of an enzyme invertase.
Glucose and fructose undergo fermentation in the presence of another enzyme, zymase, which
is found in yeast.
In wine making, grapes are the source of sugars and yeast. As grapes ripen, the quantity of
sugar increases and yeast grows on the outer skin. When grapes are crushed, sugar and the
enzyme come in contact and fermentation starts. Fermentation takes place anaerobic
conditions i.e. in absence of air. Carbon dioxide is release during fermentation.
The action of zymase is inhibited once the percentage of alcohol formed exceeds 14 percent. If
air gets into fermentation mixture, the oxygen of air oxidizes ethanol to ethanoic acid which in
turn destroys the taste of alcoholic drinks.
Ethanol is a colourless liquid with boiling point 351 K. It is used as a solvent in paint industry
and in the preparation of a number carbon compounds. The commercial alcohol is made unfit
for drinking by mixing in it some copper sulphate (to give it a colour) and pyridine (a foul
smelling liquid). It is known as denaturation of alcohol.
6. Ethanol can be derived by fermentation of material containing sugar:-
Sugars: Cane sugar, sugar beet, fruits, grapes.
Starches: Grains, potatoes, root crops.
Cellulose: Wood, grasses, crop residue etc.
The reactions are as follows:-
C6H10O6+ H₂O CH1206
(starch) Enzyme (Glucose)
CH1206 2C₂H5OH + 2CO₂
(Glucose) Yeast (Ethanol)
Fermentation temperature 20°C to 30°C process completed in 50 hours, yields
90% Alcohol content is 10 to 20% depending upon alcohol tolerance of yeast. This is
increased by distillation.
7. Fig. shows the schematic diagram of ethanol production from sugarcane.
Lime Juice SO₂
Sugarcane Cane juice Clarified Juice Sugar
Molasses
Ethanol
Fermentation
Filtered
P R O D U C T I O N O F E T H A N O L
8. • The cane is cut and ground and cane juice is extracted.
• After clarification and concentration through evaporation, the juice is fermented with yeast to
produce raw ethanol. A series of distillation steps, including a final extractive distillation with
benzene, are used to obtain anhydrous ethanol.
• Ethanol yield is 6 times higher if sugarcane juice is directly fermented instead of molasses.
One tonne of sugarcane with sugar content of 13% yields about 70 litres of ethanol through
direct fermentation of juice. Sugar content in molasses is only 2%.
• Ethanol being a high octane fuel raises the octane rating of the mixture (Octane rating is the
quality of the fuel to increase its antiknocking property)
10. P R O D U C T I O N O F M E T H A N O L
Methanol, CH3OH, also known as 'wood spirit', was produced b destructive distillation of wood.
Today, most of the methanol produced by catalytic hydrogenation of carbon monoxide at high
pressure and temperature and in the presence of catalyst.
Methanol is a colourless liquid and boils at 337 K. It is high poisonous in nature. Ingestion of
even small quantities of methanol can cause blindness and large quantities causes even death.
Methanol is used as a solvent in paints, varnishes and chiefly for making formaldehyde.
11. Fig. shows schematic diagram of methanol production from municipal wastes:
Methanol
purification
CO2
removal
Gasifier
Gas
scrubbing
Acid gas
removal
Methanol
synthesis
Iron removal
Co-shift
conversion
SHREDDED
WASTE
Methanol
12. • The wastes are shredded and passed through magnets to remove iron.
• The iron-free wastes are gasified with O2.
• The product synthesis gas is scrubbed by water to remove particulates, entrained
oil, H2S and CO2.
• Co-shift conversion for H2/CO2/CO ratio adjustment, methanol synthesis and methanol
purification are accomplished to produce methanol.
14. APPLICATION OF ETHANOL
Over 80% of the world's ethanol production is used in the fuel sector.
92.4%ethanol is used as solvent in cosmetics pharmaceuticals and chemical industry
E5 may contain a maximum of 5 vol.-% Bioethanol. It is currently the standard petrol in
Europe.
➤ In many medicines and drugs.
As a disinfectant and in tinctures.
Used as a biofuel (99.2%).
Medically ethanol is soporific and Used as antiseptic.
Fluid in many alcohol thermometer.
Most commonly used to increase octane and improve the emissions
quality of gasoline.
15. A P P L I C AT I O N O F M E T H A N O L
Methanol, also known as wood alcohol, can be used as an alternative fuel in
flexible fuel vehicles that run on M85.
The benefits include lower emissions, higher performance, and lower risk of
flammability than gasoline.
Methanol can easily be made into hydrogen for hydrogen fuel cell vehicles in the
future.
Methanol is extremely corrosive, requiring special materials for delivery and
storage.
16. L I M I TAT I O N O F U S I N G B I O - F U E L S
Disadvantages of using biodiesel produced from agricultural crops involve additional land
use, as land area is taken up and various agricultural inputs with their environmental effects
are inevitable. Switching to biodiesel on a large scale requires considerable use of our
arable area.
Transportation & storage of biodiesel require special management. Some properties of
biodiesel make it undesirable for use at high concentrations. For example, pure biodiesel
doesn't flow well at low temperatures, which can cause problems for customers with
outdoor storage tanks in colder climates.
A related disadvantage is that biodiesel, because of its nature, can't be transported in
pipelines. It has to be transported by truck or rail, which increases the cost.
Biodiesel is less suitable for use in low temperatures, than petrol diesel.
17. C O N C L U S I O N
From this , we have concluded that we should go for biofuels instead of fossil fuels .
Because it will reduce pollution which is being produced due to fossil fuels used in
the vehicles.
Although biofuels have some limitations of using , Biofuels are superior than Fossil
fuels.
R E F E R E N C E S
We have referred the Book “Introduction To Non Conventional Energy Sources” by R. K.
Rajput.
https://www.slideshare.net/PrakashKanuri1/ethanol-production-89088336
If you need further information you can find it on MNRE website and other too. You an
also refer Book by “B. H. Khan ” for more details.