Mathieu ETIENNE
CNRS - Université de Lorraine, LCPME, Nancy, [email protected]
Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l’EnvironnementUMR 7564, CNRS – Université de Lorraine,405, rue de Vandoeuvre, 54600 Villers-lès-Nancy, France.
1
Processus électromicrobiologiques pour le traitement des eaux
Journées de Promotion Procédés Produits (J3P)2018 – Procédés électrochimiques avancés pour le traitement des eaux – Jeudi 5 Juilletcampus de l’Ensic, Nancy, 1 rue Grandville 54000 Nanc
• Biofilm is an organized bacteria community embedded in autoproducedextracellular polymeric substances and fixed on a support
2
• About 109 bacteria cells by cm3 of biofilm
• Found on many type of surfaces : living tissues, sols, metals or chirurgical devices, …
Biofilm E. coli, Ch. Beloin, J.-M. Ghigo, Instit. Pasteur Paris
Biofilm E. coli, B.A. Annous and al., Food Science 2009
Biofilm
• Present a problem of diseases riskin hospital and contamination infood storage
• Many beneficial applications in environment as biodepollution, water treatment and energy production in microbial fuel cell
3
S. Pinck, F. Jorand, M. Etienne, Electrochemistry of Biofilms, in: Ref. Modul. Chem. Mol. Sci. Chem. Eng., Elsevier, 2017. doi:10.1016/B978-0-12-409547-2.13805-3.
Extracellular electron transfer in electroactive biofilm
CymA
MtrA
MtrB
MtrCOmcA OmcA
Electrodee - e -
e -
e -
e -
OM
PS
IMMenaquinol pool
Outer membrane
Periplasme
Inner membrane
Shewanella oneidensis
S. Pinck, F.P.A. Jorand, M. Etienne, Electrochemistry of Biofilms, in: Encycl. Interfacial Chem. Surf. Sci. Electrochem., 2017. doi:10.1016/B978-0-12-409547-2.13805-3.
• Shewanella oneidensis MR-1 as electroactive bacteria
• c1 from bovin heart as electron shuttle
• Multi-walled carbon nanotubes (MWCNT) as conductive nanowire
ELECTRODE
Living & conductivebiocomposite
Formate CO2
CNT
Cytochrome cBacteria
e-
5
MWCNT
S. Pinck, M. Etienne, M. Dossot, F.P.A. Jorand, A rapid and simple protocol to prepare a living biocomposite that mimics electroactive biofilms, Bioelectrochemistry. 118 (2017) 131–138. doi:10.1016/j.bioelechem.2017.07.010.
The system that we have studied
2 µm 2 µm 2 µm
A B C
In the suspension On a glassy carbon electrode
ELECTRODE
Living & conductivebiocomposite
Formate CO2
CNT
Cytochrome cBacteria
e-
A biofilm-like biocomposite
7
MWCNT
c1
Extracellular space
Outer membrane
Periplasmic space
Inner membrane
Cytoplasm
Oxidation of formate: bioanode
8
50 mV.s-1
S. oneidensis MR-1MWCNTand c1
Electrochemical responses of the biocomposites
-0.6 -0.4 -0.2 0.0 0.2 0.4 0.6-8
-6
-4
-2
0
2
4
6
8
J /
µA
cm
-2
E vs. Ag/AgCl / V
9
50 mV.s-1
S. oneidensis MR-1MWCNTand c1
in presence of 0.3 mM formate
Electrochemical responses of the biocomposites
-0.6 -0.4 -0.2 0.0 0.2 0.4 0.6-8
-6
-4
-2
0
2
4
6
8
J /
µA
cm
-2
E vs. Ag/AgCl / V
10
Reduction of fumarate: biocathode
MWCNT
Exogenous cytochromeExtracellular space
Outer membrane
Periplasmic space
Inner membrane
Cytoplasm
11
5 mV.s1
Electrochemical responses of the biocompositesMade with Shewanella oneidensis, MWCNT and c3 Desulfovibrio vulgaris Hildenborough
-500 0 500
-250
-200
-150
-100
-50
0
50
100
150
I /
µA
E vs. SHE / mV
no fumarate
50 mM fumarate
S. Pinck, M. Xu, R. Clément, E. Lojou, F.P.A. Jorand, M. Etienne, Influence of cytochrome charge and potentialon the cathodic current of electroactive artificial biofilms, Bioelectrochemistry. (2018) under revision.
Anaerobic electron transfer pathways
Y. Chen, F. Wang, Front. Mar. Sci. 2015, 1, 1–9.
K. Rabaey, R.A. Rozendal, Microbial electrosynthesis - revisiting the electrical route for microbialproduction., Nat. Rev. Microbiol. 8 (2010) 706–16. doi:10.1038/nrmicro2422.
E versus SHE
Standard electrode potential calculated from Gibbs free energy data
The purpose of nitrate removal
EU regulations[1]:
• 50 mg/l of nitrate
• 0,5 mg/l of nitrite
• The following condition must be achieved:
[nitrate]/50 + [nitrite]/3 ≤ 1
However, water with >25 mg/l of nitrate should already be purified.[2]
USA regulations[3]:
• 10 mg/l of nitrate
• 1 mg/l of nitrite
The water intended for human consumption may contain maximum: The effects of too high concentration of nitrate:
On humans:
• Methemoglobinemia (blue baby syndrome)
• Carcinogenicity (gastric cancer)
On animals:
• Bad flavor and taste as well as toxic effect on fish
On the environment:
• Eutrophication of lakes and rivers[4]
[1]: COUNCIL DIRECTIVE 98/83/EC of 3 November 1998 on the quality of water intended for human consumption[2]: E. France, Pratiques agricoles et nitrates dans les milieux aquatiques, Collect. Les Syntheses 11 (2014) 16.[3]: United States Environmental Protection Agency (USEPA), 2009. EPA 816-F-09-004: National Primary Drinking Water Regulations Table.[4]: Ghafari, S., Hasan, M., Aroua, M. K., 2008 Bio-electrochemical removal of nitrate from water and wastewater—A review, Bioresour. Technol. 99, 3965-3974
Four reduction steps towards nitrogen gas (N2)[1]
• 𝑁𝑂3− + 2 𝑒− + 2 𝐻+ → 𝑁𝑂2
− + 𝐻2𝑂
𝐸°′ = +0,433 𝑉 𝑣𝑠 𝑆𝐻𝐸
• 𝑁𝑂2− + 𝑒− + 2 𝐻+ → 𝑁𝑂 + 𝐻2𝑂
𝐸°′ = +0,350 𝑉 𝑣𝑠 𝑆𝐻𝐸
• 𝑁𝑂 + 𝑒− + 𝐻+ → 1 2𝑁2𝑂 + 1 2𝐻2𝑂
𝐸°′ = +1,175 𝑉 𝑣𝑠 𝑆𝐻𝐸
• 1 2𝑁2𝑂 + 𝑒− + 𝐻+ → 1 2𝑵𝟐 + 1 2𝐻2𝑂
𝐸°′ = +1,355 𝑉 𝑣𝑠 𝑆𝐻𝐸
In total, 2 moles of nitrate and 10 moles of electrons per 1 mole of gas nitrogen (N2) are used:
• 2 𝑁𝑂3− + 10 𝑒− + 12 𝐻+ → 𝑁2 + 6 𝐻2𝑂
[1]: Clauwaert, P., Verstraete, W. et al., 2007, Biological Denitrification in Microbial Fuel Cells, Environ. Sci. Technol. 41, 3354-3360.
Microbial fuel celL
Organic matter
CO2
Cathode
e- e-
H+
PEM
Anode
O2
H2O
resistor
Air sparger
multimeter computer
Logan, B., Microbial Fuel Cells, John Wiley and Sons Inc, Hoboken, New Jersey, 2008.
Anodicbiofilm
Microbial fuel Cell for denitrification
Organic matter
CO2
resistor
e- e-
H+
PEM
Anode
NO3-
NO2-
N2
Cathode
Anodic biofilm
Cathodic biofilm
multimeter computer
Sediment microbial fuel cell
Aerobic zone - water
Anaerobic zone - sedimentSediment CO2
O2 H2O
H+ resistor
e-
e-Zabihallahpoor, A., Rahimnejad, M.,Talebniaab, F., 2015, Sedimentmicrobial fuel cells as a new source ofrenewable and sustainable energy:present status and future prospects,RSC Adv. 5, 94171-94183.
Microbial electrochemical snorkel
Aerobic zone - water
Anaerobic zone
Organics
CO2
O2
H2O
B. Erable, L. Etcheverry, A. Bergel, From microbial fuel cell (MFC) to microbialelectrochemical snorkel (MES): maximizing chemical oxygen demand (COD) removal from wastewater., Biofouling. 27 (2011) 319–326. doi:10.1080/08927014.2011.564615.
The quantitative objective is to double the denitrification rate which is in Rampillon typically
below 350 mg of N-NO3/m2/day
Low Nitrate ANR project: to fasten the denitrification in the wetland of Rampillon with electromicrobiology
Conclusions (suite à la table ronde)
L’électromicrobiologie donne l’opportunité de coupler les processus électrochimiques et microbiologique pour le traitement des eaux
Les verrous principaux verrous pour son application hors des laboratoires est la faible conductivité des solutions (mS/cm) et une densité de courant relativement faible (A/m2)
Les processus bioanodiques sont maintenant assez bien connus
Les opportunités se situes du côté des processus biocathodiques pour favoriser des processus de dénitrification, de production de biohydrogène ou encore la récupération de métaux à forte valeur
Intérêt industriel pour les biopiles microbiennes, qui donneraient des opportunités d’innovation dans la filière traitement d’eau
AcknowledgementsLCPME
Alain WalcariusManuel Dossot
Mengjie XuL2CM
Marie-Jo StébéBIP: Elisabth Lojou, Romain Clément
LowNitrate project, ANR-17-CE04-0004 Joanna Roginska (LCPME)Frédéric Jorand (LCPME)
Christelle Despas (LCPME)Claire Genois (LCPME)
Julien Tournebize (IRSTEA)Théodore Bouchez (IRSTEA)
Alain Bergel (LGC) Frédéric Barrière (ISCR)
Thank you very much for your kind attention