Production of Bio-Electricity from Sidoarjo Mud and Molasses Using Microbial Fuel Cells (MFCs) Assisted External Resistance Technology

Mud contains little organic matter but has the potential for microbial electricigens (electrogenic) (4.5-6.6 mV) this is because the mud comes from bursts from below the earth's surface containing magma and hydrothermal fluids. Therefore, this study aims to learn the addition of Sidoarjo mud (a source of microbes as a biocatalyst) and molasses into microbial fuel cells technology for external resistance variations in generating bioelectricity. Referring to this goal, variations in molasses (2.5, 5.0 and 10 % w/w) and external resistance (1, 10, 100, 1,000 and 5,100 kΩ) were carried out. The stages in this study include starter preparation by assembling MFCs using carbon electrodes connected to electronic devices. Furthermore, the mixture of mud and molasses was put into the MFCs by immersing the anode while the cathode was on top of the mud. After that, measuring the electricity potential (voltage and power density) on various external resistances and molasses. The optimum results for the electric voltage and the best power density were obtained when using an external resistance of 1 kΩ and adding 2.5 % molasses with, respectively 210.25 mV/m² and 38.91 mW/m² (electric current 51.75 mA/m²). Based on the results of the SEM-EDX analysis for carbon electrodes, it was found that there was a change in composition from before the process to 9 weeks of running time, where the previous carbon content was 97.27 to 0.67 %. In addition, there were other contents such as sulfur, silica, ferrum, phosphorus and other elements caused by bacterial metabolism in biochemical degradation of organic components.