Performance Assessment of Multi-Electrodes Reactors for Scaling-up Microbial Fuel Cells

Abstract

The microbial fuel cells (MFCs) represent an emerging technology for converting directly organic waste into electricity. In recent years, the application of MFCs to the energy recovery from wastes has been widely explored. The main aspect that limits the development and implementation of this technology on a larger-scale is the possibility of realizing its scaling-up. In order to overcome this critical factor, it is useful to analyze novel MFCs configurations based on compact reactors with multiple electrodes.In this paper, single chamber MFCs provided with multiple fiber brush anodes and a single air-cathode were designed and realized by using a 3D printer. The reactors had a cubic shape, with a cylindrical chamber of 350 mL in volume. The mineral medium added with sodium acetate (0.25 M), as sole source of carbon and energy to sustain exoelectrogenic bacteria metabolism, were used. Anodes biofilms were prepared from a mix of compost and sodium acetate dissolved in phosphate buffer solution (0.2M), in a 1:3 ratio. The performances of two MFCs provided with two and three anodes were assessed in terms of voltage, current density and power density. These performances were compared to those of a smaller cubic MFC (30mL).

Investigating Air-Cathode Microbial Fuel Cells Performance under Different Serially and Parallelly Connected Configurations

“…Table 2 summarizes the main geometric details of this reactor. A carbon fiber brush and activated carbon coated with both a PTFE (polytetrafluoroethylene) layer and a nickel mesh (as a current collector) have been selected as the anodic and cathodic electrodes, respectively [19]. The anode size is 25 mm in diameter and 50 mm in length, each carbon fiber has a diameter of 7.2 µm and is fixed on titanium wires (the fiber brush is made by Mill-Rose); based on the mass of fibers used in a single brush and on the fiber diameter, Logan et al [20] estimated a surface area of 0.22 m 2 .…”

Inorganic Carbon Assimilation and Electrosynthesis of Platform Chemicals in Bioelectrochemical Systems (BESs) Inoculated with Clostridium saccharoperbutylacetonicum N1-H4

“…We prepared a double-folded carbon cloth (58.5 cm 2 surface area), with a Ni/Cr wire (80/20) used as the electron collector. Given the higher volume of catholyte in the 250 mL cells in comparison to the 20 mL systems, we set up composite cathodes made of carbon cloth (40 cm 2 ) wrapped with a Ni/Cr wire, used also as the electron collector, to a graphite rod of 12.5 × 0.5 cm to improve cathode volume and the overall conductivity of the electrode [ 35 ]. We prepared both anode and cathode biofilms following the same procedure previously described for the 20 mL MFCs and MECs, i.e., by culturing electroactive biofilms in Duran bottles and gradually replacing the carbon source to HCO 3 − for C. saccharoperbutylacetonicum NT-1 and glycerol for the anodic consortium.…”

Enhancement of Power Generation and Organic Removal in Double Anode Chamber Designed Dual-Chamber Microbial Fuel Cell (DAC-DCMFC)

“…Fundamentally, the configurations of MFC consist of a single chamber microbial fuel cell (SCMFC) and double chamber microbial fuel cell (DCMFC) [38]. The high performance of DCMFC is shown by the engineered electrode, such as multiple electrodes [39,40], nanomaterial-assisted electrode [41,42], low-cost material substituted electrode [43,44], separator [45,46], and multiple anode chamber called the integrated system with the wastewater treatment plant types (anaerobic digester, constructed wetland, up-flow anaerobic baffled reactor (UASB), etc.) [7,11,[47][48][49].…”