Exploring Halophilic Bacteria Bacillus clausii Isolated from Madura Salt Pond: Challenges of Utilization in Hypersaline Microbial Fuel Cells for Fish Processing Wastewater Treatment

This study investigates the influence of different NaCl concentrations on the performance of halophilic bacterial microbial fuel cells (MFCs) by using Bacillus clausii. The electron transfer rate constant (ks) revealed that MFCs operating at 10% NaCl exhibited the highest value of 2,318 s–1. The corresponding Rs and Rct values for these MFCs were determined to be 10.19 Ω and 4.74 Ω, respectively. Remarkably, the maximum power density (MPD) for MFCs at 10% salinity reached 39.79 ± 0.22 mW/m2, demonstrating a remarkable 33-fold increase compared to MFCs operating without added salinity. Furthermore, the estimated chemical oxygen demand (COD) removal efficiency for fish processing wastewater reached 95.45 ± 1.07%, with MPD of 50.92 ± 0.28 mW/m2. This study underscores the positive impact of salinity on the performance of halophilic bacterial MFCs, offering valuable insights for the optimization of MFC systems in the treatment of saline wastewater, such as fish processing industries.