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The growing demand for agricultural products has increased exponentially, causing their waste to increase and become a problem for society. Searching for sustainable solutions for organic waste management is increasingly urgent. This research focuses on considering the waste of an Andean tuber, such as Olluco, as a fuel source for generating electricity and becoming a potential sustainable energy source for companies dedicated to this area. This research used Olluco waste as fuel in single-chamber microbial fuel cells using carbon and zinc electrodes. An electric current and electric potential of 6.4 ± 0.4 mA and 0.99 ± 0.09 V were generated, operating with an electrical conductivity of 142.3 ± 6.1 mS/cm and a pH of 7.1 ± 0.2. It was possible to obtain a 94% decrease in COD and an internal resistance of 24.9 ± 2.8 Ω. The power density found was 373.8 ± 28.8 mW/cm2 and the current density was 4.96 A/cm2. On day 14, the cells were connected in earnest, achieving a power of 2.92 V and generating enough current to light an LED light bulb, thus demonstrating the potential that Olluco waste has to be used as fuel in microbial fuel cells.

The mismanagement of plastic waste, organic waste, and the shortage of electricity in remote villages has created significant challenges for industries and governments. Therefore, this research aims to utilize the fungus Trichoderma sp. as a catalyst in microbial fuel cells, where the novelty of the research is the generation of electricity and the degradation of plastic simultaneously. In this study, single-chamber microbial fuel cells were constructed using carbon (anode) and zinc (cathode) electrodes. The substrate consisted of 20 gr of potato waste and 1.5 × 1.5 cm samples of plastic waste, all combined in 390 mL of Bushnell broth, into which Trichoderma sp. was inoculated. The highest electrical readings were recorded on day 23, showing values of 5.648 ± 0.093 mA and 0.479 ± 0.025 V. On the same day, the pH level was measured at 7.046 ± 0.314, and the substrate's electrical conductivity was found to be 155.135 ± 2.569 mS/cm. Over the 45-day monitoring period, the chemical oxygen demand decreased by 78.67%. The microbial fuel cells achieved a maximum power density of 68.140 ± 2.418 mW/cm2 at a current density of 4.719 mA/cm2, with an internal resistance of 23.647 ± 1.514 Ω. Analysis of the plastic using FTIR (Fourier Transform Infrared Spectroscopy) revealed a decrease in the intensity of spectral bands associated with hydroxyl groups, C-H structural groups, methyl groups, and C=C bonds. Additionally, SEM (Scanning Electron Microscopy) images demonstrated a reduction in the thickness of the plastic film and the formation of voids and sheets, highlighting the potential of Trichoderma sp. for plastic degradation. [ABSTRACT FROM AUTHOR]

Currently, two significant problems involve the government, population, and environment: the accelerated increase in organic waste and the need to replace conventional energy with environmentally sustainable energy. The sustainable use of organic waste is being intensely investigated to generate energy plants that produce alternative sustainable electrical energy beneficial to the population at a low cost. The novelty of this research is given by the use of pepper waste as fuel in the generation of bioelectricity, giving added value to these types of waste, benefiting farmers and companies dedicated to the export and import of these fruits, because they will be able to generate their own electrical energy using their own waste at a lower cost. For this reason, this research uses pepper waste as fuel in single-chamber microbial fuel cells manufactured at a low cost as its primary objective. The maximum values of the electric current (5.118 ± 0.065 mA) and electric potential (1.018 ± 0.101 V) were shown on the fourteenth day, with an optimal operating pH of 7.141 ± 0.134 and electrical conductivity of 112.846 ± 4.888 mS/cm. Likewise, a reduction in the COD was observed from 1210.15 ± 0.89 mg/L to 190.36 ± 16.58 mg/L in the 35 days of monitoring and with a maximum ORP of 426.995 ± 8.615 mV, whose internal resistance was 33.541 ± 2.471 Ω. The peak power density was 154.142 ± 8.151 mW/cm2 at a current density of 4.834 A/cm2, and the Rossellomorea marisflavi strain was identified with 99.57% identity. [ABSTRACT FROM AUTHOR]