Competition of electrogens with methanogens for hydrogen in bioanodes

S. Georg*, I. de Eguren Cordoba, T. Sleutels, P. Kuntke, A. ter Heijne, C.J.N. Buisman

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Bioelectrochemical systems (BES) can provide an energy efficient way to recover nutrients from wastewaters. However, the electron donors available in wastewater are often not sufficient to recover the total amount of nutrients. This work investigates hydrogen (H2) as an additional substrate for bioanodes. This hydrogen can be produced in the fermentation of complex organic waste or could be recycled from the cathode. Understanding how to influence the competition of electroactive microorganisms (EAM) with methanogens for H2 gas from different sources is key to successful application of H2 as additional electron donor in bioelectrochemical nutrient recovery. Ethanol (EtOH) was used as model compound for complex wastewaters since it is fermented into both acetate and H2. EtOH was efficiently converted into electricity (e) by a syntrophic biofilm. Total recovered charge from 1 mM EtOH was 20% higher than for the same amount of acetate. This means that H2 from EtOH fermentation was converted by EAM into electricity. Low EtOH concentrations (1 mM) led to higher conversion efficiencies into electricity than higher concentrations (5 and 10 mM). Thermodynamic calculations show this correlates with a higher energy gain for electrogens compared to methanogens at low H2 concentrations. Cumulatively adding 1 mM EtOH without medium exchange (14 times in 14 days) resulted in stable conversion of H2 to e (67%–77% e) rather than methane. With H2 gas as electron donor, 68 ± 2% H2 was converted into e with no carbon source added, and still 53 ± 5% to e when 50 mM bicarbonate was provided. These results show that under the provided conditions, electrogens can outcompete methanogens for H2 as additional electron donor in MECs for nutrient recovery.

Original languageEnglish
Article number115292
JournalWater Research
Volume170
DOIs
Publication statusPublished - 1 Mar 2020

Fingerprint

Methanogens
Nutrients
hydrogen
electron
Hydrogen
electricity
Wastewater
Electricity
Electrons
nutrient
wastewater
Microorganisms
Fermentation
fermentation
acetate
microorganism
Recovery
Biofilms
Gases
bicarbonate

Keywords

  • Bioanode
  • Bioelectrochemical system
  • Fermentation
  • Hydrogen oxidation

Cite this

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title = "Competition of electrogens with methanogens for hydrogen in bioanodes",
abstract = "Bioelectrochemical systems (BES) can provide an energy efficient way to recover nutrients from wastewaters. However, the electron donors available in wastewater are often not sufficient to recover the total amount of nutrients. This work investigates hydrogen (H2) as an additional substrate for bioanodes. This hydrogen can be produced in the fermentation of complex organic waste or could be recycled from the cathode. Understanding how to influence the competition of electroactive microorganisms (EAM) with methanogens for H2 gas from different sources is key to successful application of H2 as additional electron donor in bioelectrochemical nutrient recovery. Ethanol (EtOH) was used as model compound for complex wastewaters since it is fermented into both acetate and H2. EtOH was efficiently converted into electricity (e−) by a syntrophic biofilm. Total recovered charge from 1 mM EtOH was 20{\%} higher than for the same amount of acetate. This means that H2 from EtOH fermentation was converted by EAM into electricity. Low EtOH concentrations (1 mM) led to higher conversion efficiencies into electricity than higher concentrations (5 and 10 mM). Thermodynamic calculations show this correlates with a higher energy gain for electrogens compared to methanogens at low H2 concentrations. Cumulatively adding 1 mM EtOH without medium exchange (14 times in 14 days) resulted in stable conversion of H2 to e− (67{\%}–77{\%} e−) rather than methane. With H2 gas as electron donor, 68 ± 2{\%} H2 was converted into e− with no carbon source added, and still 53 ± 5{\%} to e− when 50 mM bicarbonate was provided. These results show that under the provided conditions, electrogens can outcompete methanogens for H2 as additional electron donor in MECs for nutrient recovery.",
keywords = "Bioanode, Bioelectrochemical system, Fermentation, Hydrogen oxidation",
author = "S. Georg and {de Eguren Cordoba}, I. and T. Sleutels and P. Kuntke and {ter Heijne}, A. and C.J.N. Buisman",
year = "2020",
month = "3",
day = "1",
doi = "10.1016/j.watres.2019.115292",
language = "English",
volume = "170",
journal = "Water Research",
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}

Competition of electrogens with methanogens for hydrogen in bioanodes. / Georg, S.; de Eguren Cordoba, I.; Sleutels, T.; Kuntke, P.; ter Heijne, A.; Buisman, C.J.N.

In: Water Research, Vol. 170, 115292, 01.03.2020.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Competition of electrogens with methanogens for hydrogen in bioanodes

AU - Georg, S.

AU - de Eguren Cordoba, I.

AU - Sleutels, T.

AU - Kuntke, P.

AU - ter Heijne, A.

AU - Buisman, C.J.N.

PY - 2020/3/1

Y1 - 2020/3/1

N2 - Bioelectrochemical systems (BES) can provide an energy efficient way to recover nutrients from wastewaters. However, the electron donors available in wastewater are often not sufficient to recover the total amount of nutrients. This work investigates hydrogen (H2) as an additional substrate for bioanodes. This hydrogen can be produced in the fermentation of complex organic waste or could be recycled from the cathode. Understanding how to influence the competition of electroactive microorganisms (EAM) with methanogens for H2 gas from different sources is key to successful application of H2 as additional electron donor in bioelectrochemical nutrient recovery. Ethanol (EtOH) was used as model compound for complex wastewaters since it is fermented into both acetate and H2. EtOH was efficiently converted into electricity (e−) by a syntrophic biofilm. Total recovered charge from 1 mM EtOH was 20% higher than for the same amount of acetate. This means that H2 from EtOH fermentation was converted by EAM into electricity. Low EtOH concentrations (1 mM) led to higher conversion efficiencies into electricity than higher concentrations (5 and 10 mM). Thermodynamic calculations show this correlates with a higher energy gain for electrogens compared to methanogens at low H2 concentrations. Cumulatively adding 1 mM EtOH without medium exchange (14 times in 14 days) resulted in stable conversion of H2 to e− (67%–77% e−) rather than methane. With H2 gas as electron donor, 68 ± 2% H2 was converted into e− with no carbon source added, and still 53 ± 5% to e− when 50 mM bicarbonate was provided. These results show that under the provided conditions, electrogens can outcompete methanogens for H2 as additional electron donor in MECs for nutrient recovery.

AB - Bioelectrochemical systems (BES) can provide an energy efficient way to recover nutrients from wastewaters. However, the electron donors available in wastewater are often not sufficient to recover the total amount of nutrients. This work investigates hydrogen (H2) as an additional substrate for bioanodes. This hydrogen can be produced in the fermentation of complex organic waste or could be recycled from the cathode. Understanding how to influence the competition of electroactive microorganisms (EAM) with methanogens for H2 gas from different sources is key to successful application of H2 as additional electron donor in bioelectrochemical nutrient recovery. Ethanol (EtOH) was used as model compound for complex wastewaters since it is fermented into both acetate and H2. EtOH was efficiently converted into electricity (e−) by a syntrophic biofilm. Total recovered charge from 1 mM EtOH was 20% higher than for the same amount of acetate. This means that H2 from EtOH fermentation was converted by EAM into electricity. Low EtOH concentrations (1 mM) led to higher conversion efficiencies into electricity than higher concentrations (5 and 10 mM). Thermodynamic calculations show this correlates with a higher energy gain for electrogens compared to methanogens at low H2 concentrations. Cumulatively adding 1 mM EtOH without medium exchange (14 times in 14 days) resulted in stable conversion of H2 to e− (67%–77% e−) rather than methane. With H2 gas as electron donor, 68 ± 2% H2 was converted into e− with no carbon source added, and still 53 ± 5% to e− when 50 mM bicarbonate was provided. These results show that under the provided conditions, electrogens can outcompete methanogens for H2 as additional electron donor in MECs for nutrient recovery.

KW - Bioanode

KW - Bioelectrochemical system

KW - Fermentation

KW - Hydrogen oxidation

U2 - 10.1016/j.watres.2019.115292

DO - 10.1016/j.watres.2019.115292

M3 - Article

VL - 170

JO - Water Research

JF - Water Research

SN - 0043-1354

M1 - 115292

ER -