microbial fuel cell
DESCRIPTION
BES, microbiologyTRANSCRIPT
![Page 1: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/1.jpg)
“Microbial fuel cells prepared with Rio de la Plata river freshwater
sediments. Current production and its relationship with the change of anodophilic microbial community.”Sacco, Natalia; Pataccini, Gabriela; Bonetto, Maria Celina; Figuerola, Eva;
Cortón, Eduardo
E-mail [email protected]
Biosensors and Bioanalysis GroupBiosensors and Bioanalysis Group Biochemistry Department-School of Sciences
UBA-Ciudad Universitaria Ciudad Autónoma de Buenos Aires-Argentina
![Page 2: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/2.jpg)
What are
Microbial Fuel Cells ?
![Page 3: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/3.jpg)
Bacteria
Reducing power
Metabolism
Organic substrates (donor)
Electric Power
Operational principle
A microbial fuel cell (MFC) converts chemical energy, available
in a biodegradable substrate, directly into electricity.
Bacteria can convert a huge variety of organic compounds into CO2, water and energy. The microorganisms use the produced energy to grow and to maintain
their metabolism. However, by using a MFC we can harvest a part of this microbial energy in the form of electricity.
General principles of MFC
![Page 4: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/4.jpg)
Sedimentary Microbial Fuel Cell (SMFC)
Power is obtained from indigenous microbial communities of the sediments used.
Over 95% of the electrons resulting from anaerobic respiration can be recovered as electricity.
Lovley Nature Reviews Microbiology 4, 497–508 (July 2006) | doi:10.1038/nrmicro1442
![Page 5: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/5.jpg)
How bacteria transfer e- to the electrode?
These bacteria are called "anodophilic."
Shewanella putrefaciens, Geobacter sulfurreducens, Geobacter metallireducens , Desulfuromonas acetoxidans,and Rhodoferax ferrireducens.
![Page 6: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/6.jpg)
Work Protocol
![Page 7: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/7.jpg)
Sampling SiteSampling Site
![Page 8: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/8.jpg)
Excavation and take samples
SMFC
In situ measured pH, redox potential and T º water and mud.
Put a load resistance
Type BType A
Measure!
Sampling SiteSampling Site
DGGE
Determination of O. M
P=V2/ RI = V/R
Classical microbiological techniques
![Page 9: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/9.jpg)
Results
![Page 10: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/10.jpg)
Effect of distance between electrodes on the current production .
The distance between the anode and cathode was 8, 12, 17, 21 and 31 cm in the mud of SMFC type A (graphite disc electrode).
Higher current densityElectrode at 12 cm: 22.1 ± 0.34 mA/m2 with n = 2Electrode at 17 cm: 21.4 ± 0.10 mA/m2 with n = 2
Was observed at 221 days after the start
I biomass attached to the anode and the increase of microbial metabolism.
PB 100mM and pH7
Electrode at 12 cm: 12.2 mA/m2 and Electrode at 17 cm: 13.1 mA/m2
Characteristics of mud and water.
# The redox potential profile of the mud was negative, indicating a reduction potential that is consistent with anoxic zones.
# The pH was nearly neutral at all depths studied and collected mud.
# The water pH of 6.4
# The organic carbon content was 1.470.2 % p/p (n = 3).
![Page 11: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/11.jpg)
Study of current and potential production in type B SMFCs
SM1: mud + sodium acetate Cf 1.7 g/l. SM2 mud without added.SM3: mud + formaldehyde Cf: 5% (v/v).
Effect of addition of acetate.
Effect of electrode type.
Changes in anodophilic microbial
community.
SM3/disck SM1/ rod SM2/disck SM2/rod SM3/rod SM1/disck
0 20 40 60 80 100
0
2
4
6
8
10
12
14
16
18
20
J m
ax.
(m
W/m
2)
time (days)
![Page 12: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/12.jpg)
A) SM1 (with acetate)
Polarization curves
Power density obtained with SMFC's. Values are expressed in mW/m2
SMFCs with acetate and without it differ by approximately 25% between them with both
electrode
0 20 40 60 800
1
2
3
4
5
6
7
8
9
10
11
J(mA/m2)
Pow
er d
ensi
ty (
mW
/m2 )
A
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
E (
V)
0 10 20 30 40 50
0
2
4
6
8
10
12
14
J (mA/m2)
Pow
er d
ensi
ty (
mW
/m2 )
-0,1
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
1,1
E (
V)
B
SMFC Disk electrode Rods electrode
SM 1 8,72 ± 1,39 (n=3) 13,93 ± 3,87 (n=3)
SM 2 11,75 ± 5,33 (n=3) 18,79 ± 6,95 (n=3)
SM3 0,20 ± 0,02 (n=2) 0,27 ± 0,13 (n=2)
P max.≈ 8.5 mW/m2
P max.≈ 11.5 mW/m2
B) SM2 (without added)
![Page 13: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/13.jpg)
Denaturing Gradient Gel Electrophoresis (DGGE)
The DGGE allows a comparison of band profiles corresponding to the mud and the anodes SM1 and SM2.
The band of SM1 anode is more similar to the mud, presenting greater diversity maybe associated with the addition of an extra carbon source.
t= 3
0 d
t= 9
0 d
SM2 anode seem a lower diversity compared to initial inoculums. This could be due to the enrichment with species capable of adhering to the electrode surface and exchange electrons with it.
Bands submitted to sequence
SM2
SM1
Mud
![Page 14: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/14.jpg)
SEM of the rod electrode in SM2
(a) before placing it in the SMFC (b) electrode after 90 days of experiment in SM1(c) electrode after 90 days of experiment in SM3 ( 10000X)
Most organisms have the same morphology, these bacilli are approximately 1.25 and 2 m. Anodes in SM 1 biofilm are observed with similar characteristics to those of SM2, but
less dense.
Classical microbiological techniquesIsolate 7 possible candidates
Only one strain was a facultative anaerobic reductive iron.Majority strain was also isolated from the electrodes of the SMFC
Dietzia natronolimnaea
![Page 15: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/15.jpg)
Conclusions
![Page 16: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/16.jpg)
Compared the power densities obtained with both electrode (rod and disk),
the maximum power was observed with rod electrodes, a very cheap and accessible
material.
The addition of acetate to the sedimentary pile did not have a positive
effect on power generation.
Our set-up shows a small portion of the potential of the mud of the river “Rio de La
Plata”, because the organic matter in SMFC was never renewed.
We had a first approximation of the change in the anodophilic microbial community.
Our results with our SMFC, based on freshwater sediments have show
a performance comparable to the values obtained with SMFC in the marine
environment. Note that this is the first study of a SMFC with Rio de La Plata
river freshwater sediments.
![Page 17: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/17.jpg)
THANK YOU FOR YOUR ATTENTION!
I´m Willing to Hear your Suggestions and Answer your Questions
Integrantes
Dra. Abrevaya Ximena
Lic. Bonetto Maria Celina
Sr. Figueredo Federico
Lic. Forte Giacobone Ana
Lic. Hilding Ohlsson Astrid
Srta Gabriela Pataccini
Sr. Nuñez Pablo
Lic. Rithner Liliana
Lic. Sacco Natalia
Director: Dr. Cortón Eduardo
![Page 18: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/18.jpg)
Study the production of energy from mud from the river “ Rio de La
Plata” throught the use of sedimentary microbial fuel cell and
their relationship to changes at anodophilic microbial community
![Page 19: Microbial fuel cell](https://reader035.vdocuments.site/reader035/viewer/2022081516/558bc7c3d8b42a372c8b45f2/html5/thumbnails/19.jpg)
Types of microbial fuel cells
First generation: using soluble mediators (neutral red, methylene blue, etc..) to transfer electrons from cells to the electrode.
Second generation: the electrons are transfered through the reduction and oxidation of sulfur compounds.
Third generation: electron transfer is made directly to the electrodes.