Investigating microbial fuel cell performance by developing salt bridge from agar and activated carbon derived from pine cones

The Microbial Fuel Cell (MFC) is a sustainable innovation that treats wastewater and yields energy by degrading organic matter. An agar salt bridge is an essential component of MFC, which reduces its cost and allows hydrogen ion transfer. This study focused on using activated carbon produced from pine cones (ACPC) in the preparation of the agar salt bridge. In the present study, the concentration of agar and ACPC was varied to develop different MFC setups designated as MFC-1, 2, and 3. The optimum dose of agar and ACPC was observed in MFC-1, which contained 2% (w/v) ACPC with 8% (w/v) agar. The maximum value of open circuit voltage, current, power density, and COD removal efficiency for MFC-1 was 421 mV, 1.052 A, 61.51 mW/m2, and 65.84%, respectively. Activated carbon has a high specific surface area, allowing for a higher number of proton transfers through the agar salt bridge. Because of the effective ion transfer in MFC-1, the voltage and current values increased until day four and remained stable until day twelve, beyond which the output decreased; however, the MFC-1 continued to provide readings up to the twentieth day of the investigations. The outcome of the study clearly indicates the potential of using ACPC in agar salt bridges to enhance the efficient transportation of hydrogen ions.