Water formation at the cathode and sodium recovery using Microbial Fuel Cells (MFCs)

Gajda, Iwona; Greenman, John; Melhuish, Chris; Santoro, Carlo; Li, Baikun; Cristiani, Pierangela; Ieropoulos, Ioannis

Abstract

Microbial Fuel Cells (MFCs) utilise biodegradable carbon compounds in organic waste to generate electric current. The aim of this work was to enhance MFC performance by using low cost and catalyst (platinum)-free cathode materials. The results showed that the range of Pt-free cathodes including activated carbon, plain carbon fibre veil with and without microporous layer (MPL) in two-chamber MFCs generated power with simultaneous catholyte generation in the cathode chamber. This is the first time to report a clear catholyte formation on the cathode half cell, which was directly related to MFC power performance. The importance of this phenomenon may be attributed to the oxygen reduction reaction, water diffusion and electroosmotic drag. The synthesised catholyte in situ on the open-to-air cathode appeared to be sodium salts (9% w/v concentration), which was recovered from the anolyte feedstock containing sludge and sodium acetate. An overlooked benefit of catholyte formation and accumulation contributes greatly to the overall wastewater treatment, water recovery, bioremediation of salts and carbon capture. © 2014 Elsevier Ltd.

• Journal Article Type: Article
• Acceptance Date: May 19, 2014
• Online Publication Date: Jun 27, 2014
• Publication Date: Sep 1, 2014
• Publicly Available Date: Jun 6, 2019
• Journal: Sustainable Energy Technologies and Assessments
• Print ISSN: 2213-1388
• Publisher: Elsevier
• Peer Reviewed: Not Peer Reviewed
• Volume: 7
• Pages: 187-194
• DOI: https://doi.org/10.1016/j.seta.2014.05.001
• Keywords: microbial fuel cell (MFC), carbon veil cathodes, microporous layer (MPL), electroosmotic drag, wet scrubbing
• Public URL: https://uwe-repository.worktribe.com/output/812735
• Publisher URL: http://dx.doi.org/10.1016/j.seta.2014.05.001
• Additional Information: Additional Information : “NOTICE: this is the author’s version of a work that was accepted for publication in Sustainable Energy Technologies and Assessments. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Sustainable Energy Technologies and Assessments, [VOL7, September 2014] DOI:10.1016/j.seta.2014.05.001