Bioelectrical evaluation of microbial fuel cell fed with outlet
wastewater of the sugar industry in Egypt
Abstract
Background: Evaluation of the electricity generated by the
single-chamber mediator–less microbial fuel cell (MFC) fed with sugar
industry wastewater (SIW), besides the characterization of bacterial
diversity of anodic biofilm. Results: The maximum MFC voltage in open
circuit (OCV) mode was 911 mV after 24 operational days, while the
closed-circuit voltage (CCV) was 360 mV when 550 Ω as the external load
applied. From the polarization curve, the maximum power density of
189.16 mW/m2 as power output was observed at a current density of 370.9
mA/m2. The efficiency of the MFC was measured based on coulombic
efficiency and chemical oxygen demand (COD) removal rate. While the CE
was 51%, the COD removal efficiency reached 90.4%. The anodic biofilm
bacterial diversity was observed through several identifying
morphologically, microscopy, and molecularly. The anodic biofilm
phylogenetic bacterial consortia based on the molecular analysis of 16S
rRNA sequences was indicated seven dominant strains: Pseudomonas
aeruginosa, Lactobacillus sp., Enterococcus sp., Aeromonas hydrophila,
Bacillus methanolicus, Geothrix fermentans, and Bacillus thermocloacae
with similarity value 100% for each strain. Conclusion: These results
proposed that SIW bacterial communities in the anodic biofilm have
balanced symbiotic behavior, which has been translated into the
bioelectricity production in parallel with the SIW substrate treatment.