Agricultural wastes can be used for bioethanol production instead of food. This will help to reduce hunger. #SciChallenge2017

1. FROM CORNHUSKTO ETHANOL
Irmak Çavdar | IstanbulTerakki Foundation Schools
A novel approach to bioethanol
production that will serve both
to energy and hunger problems

4. Ethanol is an alcohol which has carbon,
hydrogen and oxygen as its components. It
is a clean and colorless liquid alcohol which
does not have poisonous effects. It is
widely produced by fermentation of food
sources like sugar cane, corn e.t.c.

5. USES OF ETHANOL:
• medicine
•fuel
• bewerages
• solvent
• Cleaning agent e.t.c.

6. The interest on renewable energy
sources have increased over years
because of economical and
environmental reasons.

7. Producing fuel on fertile land instead of
producing agricultural food have become
widely used today.
However, manufacturing fuel from
agricultural wastes instead of food should
be prioritized.

8. Cellulosic wastes are today’s most common
forms of biomass on earth. Cellulosic
materials should be decomposed to its
monomers for the microorganisms to
ferment. This procedure is known as
hydrolysis.

9. hemicellulose
hemicellulose
Pre treatment
cellulose
cellulose
Figure-1: The effect of pre-treatment on biomass

10. In this study we investigated the effect of
microwave assisted alkaline pre treatment with
lime of inedible corn husk on acid hydrolysis
and ethanol production.

11. Materials:
 Corn husk (1600 gram)
 Blender
 Lime , Ca(OH)2
 Microwave oven
 %5 by volume H2SO4
 Erlenmeyer flask (250
mL x 16)
 Yeast (Saccharomyces
cerevisiae)
 Water bath
 Autoclave
 Filter paper
 0,5 M KOH solution
 pH meter
 Distillation apparatus

12. Independent Variables:shown in Table-1.
•The amount of Ca(OH)2 used
•Temperature of the microwave (°C)
•Microwave time (hour)
Dependent Variable:
•The amount of ethanol produced
Controlled Variable:
•Agricultural wastes
•The process of acid hydrolysis
•The process of fermentation

13. Table 1: Samples testing conditions
Sample
g. Ca(OH)2/ g.
biomass
Microwave temp.
(oC)
Microwave
time(hour)
1 ------- 120 1
2 ------- 120 3
3 -------- 180 1
4 -------- 180 3
5 0,2 ----- 1
6 0,2 ----- 3
7 0,2 120 1
8 0,2 120 3
9 0,2 180 1
10 0,2 180 3
11 0,5 ----- 1
12 0,5 ----- 3
13 0,5 120 1
14 0,5 120 3
15 0,5 180 1
16 0,5 180 3

14. Alkali Pre treatment
• 100g corn husk
• 50g Ca(OH)2
• Microwave

15. Acid Hydrolysis
• 80°C
• 100mL %5 H2SO4
• 4 hours

16. Fermentation
• 40°C
• pH 3-6
• Yeast (Saccharomyces
cerevisiae)

17. Distillation

18. Results (Table 2)
Sample
g. Ca(OH)2/ g.
biomass
Microwave
temp.(oC)
Microwave
time(hour)
ethanol
produced
(mL/100 gram
biomass)
1 ------- 120 1 1
2 ------- 120 3 1
3 -------- 180 1 3
4 -------- 180 3 5
5 0,2 ----- 1 24
6 0,2 ----- 3 26
7 0,2 120 1 33
8 0,2 120 3 37
9 0,2 180 1 38
10 0,2 180 3 42
11 0,5 ----- 1 35
12 0,5 ----- 3 37
13 0,5 120 1 44
14 0,5 120 3 48
15 0,5 180 1 54
16 0,5 180 3 62

19. Ethanol produced
mL/100 g biomass
Temperature and time
No alkali
biomass
biomass

20. Conclusion
As seen in table 2, Ca(OH)2 which is a low-cost alkali, increases the efficiency of ethanol
production from cellulosic wastes. Using microwave during the pre-treatment also serve for
the purpose. In regular conditions, it would take several days however, with this process, it
only takes few hours to complete the whole procedure.
Agricultural wastes should be prefered in bioethanol production rather than using corn,
beetroot and other nutrients.
This solution can also end
hunger and energy issues
on earth.