AIMS Environmental Science (Dec 2023)
Bioelectricity production from anaerobically treated leachate in microbial fuel cell using <i>Delftia acidovorans</i> spp.
Abstract
Microbial fuel cells (MFCs) are devices that use microorganisms to produce electricity from organic matter. In this study, the bacterium Delftia acidovorans spp was used to evaluate energy generation in a single-chamber MFC. In this evaluation, six MFCs were assembled with different exchange membranes: two with carbon fiber composite membrane, two with maghemite membrane and two with heat-treated maghemite. Synthetic maghemite was characterized using X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FTIR) measurements. Bioelectricity monitoring in the MFCs was conducted for 15 days, with data collected every 60 seconds. The cell that achieved the highest bioelectricity production was the one with heat-treated maghemite, reaching a production of 286.50mV. It used 100% leachate from fruit and vegetable waste as a substrate, starting with values of 365 mg/L of N-NH4, 96000 mg/L of biochemical oxygen demand (BOD5), 101500 mg/L of chemical oxygen demand (COD) and a pH of 4.11. In the results, the carbon fiber treatment had a higher removal efficiency percentage of up to 63.38% for BOD5 and 69.67% for COD. For ammonium nitrogen removal, all cells showed good removal efficiency of up to 92.49%. The pH value increased in all treatments due to the degradation of organic matter, reaching a value of up to 5.96. Thus, the efficiency of Delftia acidovorans spp. and carbon fiber are a good alternative as an exchange membrane in purifying leachate contaminants within an MFC.
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