DESING AND CONSTRUCTION OF MICROBIAL FUEL CELLS BASED ON NATURAL MEDIATORS

Microbial fuel cells (MFC) are advanced energy conversion. The central idea behind MFCs is the ability to generate electrical power by taking advantage of materials that are defined as waste which exists in their environment (e.g. sewage). We have studied an MFC comprised of a dual-glass chamber separated by a proton conductive membrane. The anode chamber contains bacterial cells grown in acetate as a sole carbon source. Electrons and protons, produced in the acetate bio-oxidation process were with oxygen at the cathode chamber via electrochemical reduction.

Following the appearance of the green pigment in the growth medium of bacteria C. basilensis, it was discovered for the first time that these bacteria produce pyocyanin.

Examining the effect of pyocyanin that are formed by C. basilensis revealed a significant improvement of the maximum power density, 6.25 times higher in MFC compared to control.

An MFC system based on an anode with a Geobacter sulfurreducens & Cupriavidus basilensis bacterial mixture produced a maximum current density of 1460 mA/m² 1.7 times higher in comparing MFC with monoculture of G. sulfurreducens.

When comparing MFC systems based on pure or mix culture with phenol as a sole carbon source, the MFC system based on mix culture bacteria obtained the best results. The percentage removal phenol after 48 hours is 74.9 %.

In summary, in this study for the first time it has been discovered that C. basilensis bacteria produce pyocyanin, this pigment improve the current and power density in MFC. In addition, combining G. sulfurreducens bacteria was found to be effective in both improving the electrical efficiency of MFC and the phenol degradation.