Biofuel Cells and Bioelectrochemical Systems

Abstract

This special issue on biofuel cells and bioelectrochemical systems focuses on advances in microbial fuel cells (MFCs) and electrolysis cells, while introducing some new concepts facilitating practical application of these systems. In order to demonstrate feasibility of bioelectrochemical systems, one needs to compare their performance and costs with existing alternatives. The paper by Huggins et al., provides a simple comparison of MFCs vs. aerobic oxidation pits, which are commonly used for treatment of organic wastes at a low cost. The work reports results from a 15L scale unit, which demonstrates the effectiveness of MFCs and identifies an interesting configuration for development of low cost systems with application for treatment of low value streams. The working principle of a microbial fuel cell inherently requires movement of positive ions from the anodefluid to the cathode due to electrons being consumed at the cathode. A modification of a typical MFC can also allow separation of positive, as well as negative charges to respective electrodes. Gude et al., report the current status of such cells termed as microbial desalination cells and discuss their limitations and potential strategies to overcome them. They also introduce concepts based on photosynthetic MFCs to improve removal of nutrients from wastewater as a means of resource recovery, while also sequestering carbon dioxide.