Bioelectrochemical transformation of synthetic waste from the Vaal region: effects of acetic acid, sugar, and salt on biogas production and electricity generation using a microbial fuel cell

Authors

  • Wato Nathan Fundji
    Department of Chemical and Metallurgical Engineering, Faculty of Engineering and Technology, Vaal University of Technology, Private Bag X021, Andries Potgieter Blvd, Vanderbijlpark 1911, Gauteng, South Africa
  • Kitenge Marie Ngoie
    Department of Industrial Engineering, Operations Management and Mechanical Engineering, Faculty of Engineering and Technology, Vaal University of Technology, Private Bag X021, Andries Potgieter Blvd, Vanderbijlpark 1911, Gauteng, South Africa
  • Kabamba Arthur Makenda
    Department of Natural Sciences, Faculty of Applied and Computer Sciences, Vaal University of Technology, Private Bag X021, Andries Potgieter Blvd, Vanderbijlpark 1911, Gauteng, South Africa
  • John Kabuba
    Department of Chemical and Metallurgical Engineering, Faculty of Engineering and Technology, Vaal University of Technology, Private Bag X021, Andries Potgieter Blvd, Vanderbijlpark 1911, Gauteng, South Africa

Keywords:

Biogas, Microbial Fuel Cell, Vaal region, Wastewater

Abstract

This study investigated the effects of common domestic organic modifiers---acetic acid, brown sugar, and table salt---on the electrochemical, physicochemical, and bioenergetic characteristics of low-strength synthetic wastewater in a microbial fuel cell (MFC). Four wastewater matrices representing sewage from the Vaal region were prepared and maintained under anoxic conditions for 30 days. Maximum biogas production of 189 ppm and electrical output of 164 mV were recorded, indicating substrate-selective microbial activity. Fourier transform infrared spectroscopy (FTIR) confirmed structural changes in functional moieties in suspended solids and showed that salt and sugar were completely solubilized. Although biochemical oxygen demand ( < 0.3 mg L-1) and chemical oxygen demand ( < 5 mg L-1) were extremely low, the resident microbial communities remained electroactive, indicating that the MFC could recover energy even from matrices with low biodegradability. Response surface methodology (RSM) based on a central composite design (CCD) was used to model and optimize the effects of pH, exposure time, and substrate concentration on conductivity, total dissolved solids, and oxidation--reduction potential. Strong quadratic and interaction effects (p < 0.0001) indicated nonlinear interactions between redox potential and ionic strength. These findings suggest that low-cost additive strategies may improve MFC performance in dilute effluents from the Vaal region and support decentralized wastewater-to-energy applications.

Dimensions

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FIG6a

Published

2026-06-10

How to Cite

Bioelectrochemical transformation of synthetic waste from the Vaal region: effects of acetic acid, sugar, and salt on biogas production and electricity generation using a microbial fuel cell. (2026). African Scientific Reports, 5(2), 444. https://doi.org/10.46481/asr.2026.5.2.444

Issue

Volume 5, Issue 2, August 2026

Section

ENGINEERING SECTION
Copyright & Licensing

Copyright (c) 2026 Wato Nathan Fundji, Kitenge Marie Ngoie, Kabamba Arthur Makenda, John Kabuba

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Bioelectrochemical transformation of synthetic waste from the Vaal region: effects of acetic acid, sugar, and salt on biogas production and electricity generation using a microbial fuel cell. (2026). African Scientific Reports, 5(2), 444. https://doi.org/10.46481/asr.2026.5.2.444

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