Acompanhamento da geração de potencial elétrico por célula combustível microbiana

Abstract

The microbial fuel cell is a system which can generate electric power at the same time which degrades organic matter. The present work aims the installation and operation of microbial fuel cells and evaluation of electric power generation. The system is operated by the addition of a substrate to the cell. When substrate’s nutrients are degraded occurs the conversion of the chemical bond energy into electrical energy by the process of respiration. The microbial fuel cells were made with ordinary materials, each chamber has 170mL of substrate and were connected by a salt bridge.Was realized a 2³ experiment, changing the microorganism (Escherichia coli and Pseudomonas aeruginosa), substrate (mineral and lactate) and the material of the electrode (copper – iron and copper – graphite). The experiment was made into duplicate, during 20 days with constant temperature of 37ºC. The best results were obtained in cells with lactate medium and graphite (anode) and copper (cathode) electrodes. The MFC inoculated with E. coli peaked at 0.47 V and inoculated with P. aeruginosa reached 0.46 V on a daily measurement. The ANOVA statistical analysis showed that the microorganism and the interaction between the electrode and the substrate were significant variables in the generation of electric potential cumulative, with the highest value observed with P. aeruginosa grown in culture medium lactate and taking MFC copper-graphite electrodes (8, 16 V).