Electricity production from molasses wastewater in two-chamber microbial fuel cell

Abstract

Molasses wastewater contains large amounts of glucose, and it can provide enough energy for microbial decomposition. The microbial fuel cell (MFC) in this study was demonstrated to be able to treat real wastewater with the benefit of harvesting electricity energy. Efficient operation of this MFC requires a molasses wastewater and preferably an inexpensive anode electrolyte. The results from a batch of experiments showed that molasses wastewater could not only serve as the electron acceptor in anode, but also generate electricity stably. A maximum voltage output of 514.5 mV and a maximum power density of 65.82 mW/m² were recorded at external resistance of 1,000 Ω. The MFC not only effectively dealt with the molasses wastewater, the chemical oxygen demand removal rate is 81.22%, but also had a significant effect in the processing of analog silver wastewater. At the end of the experiment, after disassembling the device, silver precipitation was found stacked on the cathode carbon paper electrode, and some black sediment was found at the side of the proton membrane anode.

Key findings

• ▸Molasses wastewater can serve as an electron acceptor and generate electricity in an MFC.
• ▸The MFC can effectively remove COD from molasses wastewater, with a removal rate of 81.22%.
• ▸The MFC can also process analog silver wastewater, with silver precipitation observed on the cathode carbon paper electrode.

Keywords

Identifiers

DOI

10.2166/wst.2013.261

Journal

Water Science and Technology

Year

2013