الفهرس 
Chapter One : IntroductionOnly 14 pages are availabe for public view
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Abstract
A Microbial fuel cell (MFC) is a system that converts chemical energy to electrical energy during substrate oxidation with the aid of microorganisms that act as biocatalysts. Microbial fuel cells (MFCs) are the promising technique that could utilize organic compounds in wastewater as fuel for power generation, simultaneously tackling energy and environmental problems. MFCs based technologies for real applications in waste and wastewater treatment processes. However, MFCs have not yet been used for practical applications due to their low power outputs, the high cost especially dependence on precious metal catalysts (Platinum (Pt) and Pt-alloys), and challenges associated with scale-up. In this study, more cost-effective catalyst materials were investigated to generate power from real industrial wastewater without the addition of external microorganisms or chemicals by using single chamber air cathode-MFCs. The anode material is the main key component in the MFCs due to its effect on bacteria attachment, the electron transfer process, and substrate oxidation. Thus, herein, two catalysts synthesized based on modification of different anode materials. First, Tungsten carbide (WC) and tungsten carbide on reduced graphene oxide (WC+rGO) nanolayers show outstanding performance as anode catalysts in microbial fuel cells for the simultaneous generation of power and treatment of wastewater. In this work, these catalysts synthesized using simple and cost-effective urea glass route and reduction-carburization techniques. The pristine carbon felt (CF), WC/CF, and WC+rGO/CF anodes were characterized using several techniques and tested in a practical microbial fuel cell using industrial wastewater. The unique features of WC/CF and WC+rGO/CF anodes, i.e., the surface area, biocompatibility, structure morphology, and catalytic activity, resulted in significant performance improvements. In particular, WC+rGO/CF exhibited a 4.4-, 7.6-, and 2.1-fold power density, current density, and coulombic efficiency, respectively, relative to the pristine CF anode. This study confirms the potential use of WC+rGO/CF as a viable anode catalyst in microbial fuel cells on a larger scale. Second, Iron/iron oxide (Fe/Fe2O3) nanoparticles were deposited on the surface of different carbonaceous anode materials: carbon felt (CF), carbon cloth (CC), and graphite (G) as an effective catalyst to improve the anode performance of microbial fuel cell (MFC) based on the real industrial wastewater. Interestingly, the results of the characterization indicated the novel structure of the iron nanoparticles enveloped with a thin layer of iron oxide formed on the anode surfaces. This novel structure enhances the surface wettability of the electrode, the degradation reactions rate of organic compounds, and the microorganism adhesion on the electrode surface, and decreases the electron transfer resistance. Therefore, the generated power and current were considerably improved, where the generated power was increased by 385%, 170%, and 130%, for the CF, CC, and G electrodes, respectively. Moreover, the MFC based on the modified electrodes achieved the excellent removal percentage (more than 80%) of organic compounds from wastewaters.