Anode amendment with kaolin and activated carbon increases electricity generation in a microbial fuel cell

Lea Ouaknin Hirsch; Irina Amar Dubrovin; Bharath Gandu; Efrat Emanuel; Birthe Veno Kjellerup; Gizem Elif Ugur; Alex Schechter; Rivka Cahan

doi:10.1016/j.bioelechem.2023.108486

Anode amendment with kaolin and activated carbon increases electricity generation in a microbial fuel cell

Bioelectrochemistry. 2023 Oct:153:108486. doi: 10.1016/j.bioelechem.2023.108486. Epub 2023 Jun 7.

Authors

Lea Ouaknin Hirsch¹, Irina Amar Dubrovin¹, Bharath Gandu², Efrat Emanuel¹, Birthe Veno Kjellerup³, Gizem Elif Ugur⁴, Alex Schechter⁵, Rivka Cahan⁶

Affiliations

¹ Department of Chemical Engineering, Ariel University, Ariel 40700, Israel.
² Department of Chemical Engineering, Ariel University, Ariel 40700, Israel; Department of Environmental Studies, University of Delhi, New Delhi 110007, India.
³ Department of Civil and Environmental Engineering, University of Maryland, 1147 Glenn L Martin Hall, College Park, MD 20742, USA.
⁴ Imaging and Chemical Analysis Laboratory, Montana State University, Montana 59715, USA.
⁵ Department of Chemical Sciences, Ariel University, Ariel 40700, Israel.
⁶ Department of Chemical Engineering, Ariel University, Ariel 40700, Israel. Electronic address: rivkac@ariel.ac.il.

PMID: 37302334
DOI: 10.1016/j.bioelechem.2023.108486

Abstract

The bacterial anode is a key factor for microbial fuel cell (MFC) performance. This study examined the potential of kaolin (fine clay) to enhance bacteria and conductive particle attachment to the anode. The bio-electroactivity of MFCs based on a carbon-cloth anode modified by immobilization with kaolin, activated carbon, and Geobacter sulfurreducens (kaolin-AC), with only kaolin (kaolin), and a bare carbon-cloth (control) anodes were examined. When the MFCs were fed with wastewater, the MFCs based on the kaolin-AC, kaolin, and bare anodes produced a maximum voltage of 0.6 V, 0.4 V, and 0.25 V, respectively. The maximum power density obtained by the MFC based on the kaolin-AC anode was 1112 mW‧m^-2 at a current density of 3.33 A‧m^-2, 12% and 56% higher than the kaolin and the bare anodes, respectively. The highest Coulombic efficiency was obtained by the kaolin-AC anode (16%). The relative microbial diversity showed that Geobacter displayed the highest relative distribution of 64% in the biofilm of the kaolin-AC anode. This result proved the advantage of preserving the bacterial anode exoelectrogens using kaolin. To our knowledge, this is the first study evaluating kaolin as a natural adhesive for immobilizing exoelectrogenic bacteria to anode material in MFCs.

Keywords: Activated carbon; Coulombic efficiency; Kaolin; Microbial fuel cell; Modified anode.

MeSH terms

Bacteria
Bioelectric Energy Sources* / microbiology
Charcoal
Electricity
Electrodes
Kaolin

Substances

Charcoal
Kaolin