Sustainable Use of the Fungus Aspergillus sp. to Simultaneously Generate Electricity and Reduce Plastic through Microbial Fuel Cells

Abstract

The improper disposal of plastic waste has become a significant problem, with only a small amount recycled and the rest ending up in landfills or being burned, leading to environmental pollution. In addition, the cost of electric energy has risen by over 100% in the last 20 years, making it unaffordable for remote areas to access this service due to high installation costs, leaving people living far from major cities without electricity. This study proposes an innovative solution to these issues using microbial fuel cell (MFC) technology to simultaneously reduce plastic waste and generate electric energy by utilizing the fungus Aspergillus sp. As a substrate for 45 days. The MFCs reached maximum values of 0.572 ± 0.024 V and 3.608 ± 0.249 mA of voltage and electric current on the thirty-first day, with the substrate operating at a pH of 6.57 ± 0.27 and an electrical conductivity of 257.12 ± 20.9 mS/cm. Furthermore, it was possible to reduce the chemical oxygen demand by 73.77% over the 45 days of MFC operation, while the recorded internal resistance was 27.417 ± 9.810 Ω, indicating a power density of 0.124 ± 0.006 mW/cm2. The initial and final transmittance spectra, obtained using FTIR (Fourier Transform Infrared), showed the characteristic peaks of polyethylene (plastic), with a noticeable reduction in the final spectrum, particularly in the vibration of the C-H compound. After 45 days of fungus operation, the plastic surface used as a sample exhibited perforations and cracks, resulting in a thickness reduction of 313.56 µm. This research represents an initial step in using fungi for plastic reduction and electric energy generation in an alternative and sustainable manner.