Gsf final 3

Google Science Fair 2013

Chung Ray ErnNg Yu Song

Hari Kope[Teacher Mentor] Mrs Yau Pooi Har

Urine to Fuel

Introductory Video

http://www.youtube.com/watch?v=vJqP1EcV9ZY


The Need

- Increased need for renewable sources of energy

- Renewable?

- Environmentally friendly?

- Inexpensive?

- Producing fuel from Petrol

- Non-renewable

- Fast-depleting

- Not Environmentally Friendly


The Need

- Attempts at incorporating waste and renewable energy

- World population of 7 billion

- Average person produces 1.5 liters of urine a day

- 11 billion liters of urine produced a day

- Producing hydrogen as a fuel from urine

- Renewable

- Cheap

- Environmentally friendly


Our Goal

Electricity

Electrolysis of Urine Electricity

Fuel Cell

Hydrogen Engine

Aim: To investigate the factors affecting the rate of electrolysis of urine to ensure a maximum rate of the production of hydrogen.


The Theory

Video on Electrolysis of Urea

Electrolysis of Urea

http://www.youtube.com/watch?v=k9Oh--ICQk4

http://www.youtube.com/watch?v=k9Oh--ICQk4


The Theory

How a hydrogen fuel cell works:


The Scope

We investigated 4 factors:

• Concentration of Urea

• Material of Electrode

• Alkalinity

• Surface Area of Electrode


The Procedure

Urea solution

graphite

anode

(+)

graphite cathode

(-)

1. The electrolytic cell was set up (as shown in the diagram on the left).

2. Varying concentrations of urea were poured into the cell.

3. Sodium hydroxide was poured into the cell, acting as a catalyst for the electrolysis.

4. The transformer was set to 12 volts of current.


The Procedure

5. The timer was started when the transformer was turned on, and stopped when hydrogen collected had reached the mark.

6. The gas collected was tested with a lighted splint.


The Procedure

7. The experiment was repeated with varying concentrations of urea of 0.1, 0.5, 1.0, 1.5 and 2.0 mol/dm3 (1st

experiment), varying electrode materials of brass, copper, stainless steel, iron (2nd experiment) and varying concentrations of sodium hydroxide of 0.5, 1.0, 5.0 and 10.0 cm3 (3rd

experiment).


The Procedure

9. The experiment testing the surface area of the electrodes required a different set-up. A large electrolytic cell made from a plastic pail fitted with two crocodile clips was specially made for this investigation.


The Procedure

10. Steel electrodes of varying surface areas (weighing 3g, 6g, and 9g) were clipped onto the crocodile clips. A filter funnel was inverted to cover the entire piece of steel cathode, with a boiling tube filled with urea solution inverted over the stem of the filter funnel to collect the hydrogen gas while a pair of pliers holding the filter funnel in place.


The Results

Concentration of Urea/M

Ave

rage

tim

e ta

ken

fo

r p

rod

uct

ion

of

hyd

roge

n/m

in

0

1

2

3

4

5

6

0.1M 0.5M 1.0M 1.5M 2.0M

2.59

3.553.64

4.21

5.17


The Results

Type of electrodes used

Ave

rage

tim

e ta

ken

fo

r p

rod

uct

ion

of

hyd

roge

n/m

in

0

1

2

3

4

5

6

Carbon Copper Steel Brass Iron

3.92

5.21

4.23

3.41

2.38


The ResultsA

vera

ge t

ime

take

n f

or

pro

du

ctio

n o

f h

ydro

gen

/min

Amount of Sodium Hydroxide Solution (cm³)

0

5

10

15

20

25

30

35

40

45

0.5 1 5 10

40.55

6.38

3.68

21.65


The ResultsA

vera

ge t

ime

take

n f

or

pro

du

ctio

n o

f h

ydro

gen

/s

Mass of cathode: Mass of anode

0

20

40

60

80

100

120

3g:3g 3g:6g 3g:9g 6g:3g 6g:6g 6g:9g 9g:3g 9g:6g 9g:9g

95.3

74.064.0

74.7

82.7

94.0

66.3

82.7

77.3


The Hydrogen Generator

•A hydrogen generator was constructed using the optimal factors identified. •To increase the effectiveness of the urine car.


The Hydrogen Generator

•Surface Area of Steel Electrodes = (10 x 8) cm2

•Number of Steel Plates used as Anode/Cathode = 6•Electrolyte Used= 0.5 mol/dm3

of urea + 0.5 mol/dm3 of sodium hydroxide


The Prototype Car

A prototype car was assembled to test our hydrogen generators.

Voltage generated by the two Hydrogen Generators connected in series was 2.07 volts and was sufficient to power the prototype car.

Video: Car running on Hydrogen Generator

http://www.youtube.com/watch?v=6GUXGLhEM9w


Conclusion

• Rate of production of hydrogen gas decreases with increased concentration of urea• Fastest rate of electrolysis of urea using copper electrodes

•copper reacts with the sodium hydroxide• stainless steel electrodes are the next best option

• Sodium hydroxide solution added to the electrolyte • strong alkali, good conductor due to free moving ions speeds up electrolysis• also helps absorbs carbon dioxide produced

•electrodes used should have a large surface area• allows for more ions to be oxidised and reduced

Gsf final 3

Design

Transcript of Gsf final 3