Conventional vegetable waste: a potential source for the high performance of benthic microbial fuel cells

One of the most advanced types of bioelectrochemical systems is the benthic microbial fuel cells (BMFCs). It can remove metals and other pollutants from wastewater while also generating electricity. Previous studies have shown that BMFCs have a problem producing enough electrons from their organic substrates to electrochemically convert soluble metals into insoluble forms. A stable and readily oxidizable organic substrate is required for BMFCs to promote bacterial growth and increase electron generation. This study thus focuses on the modern trend of using waste as an organic substrate, and we used sweet potato waste. The findings revealed that when this waste was used as an organic substrate, it generated 154 mV in 15 days with the maximum power density, i.e., 1.450 mW/m². Additionally, more than 90% of the various metals were removed, and around 70% of the chemical oxygen was removed. Additionally, electrochemical experiments reveal a rapid rate of oxidation of sweet potato waste. The internal resistance of BMFCs was 724 Ω (Rct = 21.30 Ω and Rs = 702.7 Ω) on day 15. High resistance on day 15 is probably caused by solution conductivity. On day 15, the voltage was high before decreasing. The biofilm formation growth was gradual until day 25, as evidenced by specific capacitance data. Finally, parameter optimization, mechanism discussion, and future prospects are well explained in this article.