Membrane-less microbial fuel cell: effect of pH on the electricity generation powered by municipal food waste

Abstract

Abstract Fossil fuels have supported the industrialization and economic growth of countries during the past centuries and it is clear that they cannot indefinitely sustain in a longer time. In this study, membrane-less microbial fuel cell (ML-MFC) with mediators-less and air cathode had potential solution to generate electricity power and at the same time could reduce the abundant of food waste (1.64 kg/daily, around 8 tonnes/year) which dumped in the landfill and it’s cost effective device. The ML-MFC operated electrochemically incorporate electrogenic bacteria (EB) acted as a biocatalyst in order to produce electricity. The performance and optimization performance of food waste was evaluated using one-factor-at-a-time (OFAT) method and it was focused to pH for power generation. To determine the generated electricity the polarization curve was used to evaluate the performance of ML-MFC. The chemical oxygen demand (COD) of food waste was studied. The optimization of pH condition in ML-MFC was ranging from 7 to 9. Results showed that pH 8 was the optimum pH for EB strain, Bacillus Subtilis , with the high voltage (807 mV), EB biomass (15.46 mg/L), and power density (373.3 mW/m 2 ) generated. Clearly the pH environment condition affected the efficiency of ML-MFC performance. The increase in EB biomass also increased the voltage in the ML-MFC, proving that EB biomass and voltage were associated with growth.

Key findings

• ▸The ML-MFC with air cathode and mediators-less generated electricity with electrogenic bacteria (EB) as biocatalyst.
• ▸The optimal pH for EB strain Bacillus Subtilis was found to be 8, resulting in a high voltage of 807 mV.
• ▸The chemical oxygen demand (COD) of food waste was studied, but no specific findings were mentioned.

Keywords

Identifiers

DOI

10.1088/1742-6596/2129/1/012095

Journal

Journal of Physics: Conference Series

Year

2021