A new method for urine electrofiltration and long term power enhancement using surface modified anodes with activated carbon in ceramic microbial fuel cells. (1st September 2020)

• Record Type: Journal Article
• Authors: Gajda, Iwona; You, Jiseon; Santoro, Carlo; Greenman, John; Ieropoulos, Ioannis A.
• Is Part Of: Electrochimica acta. Volume 353(2020)
• Publication Date: 2020-09-01
• Subjects: Microbial fuel cell -- Activated carbon -- Micro-nanostructure -- Ceramic membrane -- Catholyte production -- Urine; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.136388
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: This work is presenting for the first time the use of inexpensive and efficient anode material for boosting power production, as well as improving electrofiltration of human urine in tubular microbial fuel cells (MFCs). The MFCs were constructed using unglazed ceramic clay functioning as the membrane and chassis. The study is looking into effective anodic surface modification by applying activated carbon micro-nanostructure onto carbon fibres that allows electrode packing without excessive enlargement of the electrode. The surface treatment of the carbon veil matrix resulted in 3.7 mW (52.9 W m −3 and 1626 mW m −2 ) of power generated and almost a 10-fold increase in the anodic current due to the doping as well as long-term stability in one year of continuous operation. The higher power output resulted in the synthesis of clear catholyte, thereby i) avoiding cathode fouling and contributing to the active splitting of both pH and ions and ii) transforming urine into a purified catholyte - 30% salt reduction - by electroosmotic drag, whilst generating - rather than consuming – electricity, and in a way demonstrating electrofiltration. For the purpose of future technology implementation, the importance of simultaneous increase in power generation, long-term stability over 1 year and efficient urine cleaning by using low-cost materials, is very promising and helps the technology enter the wider market. Graphical abstract: A new method for urine electrofiltration and long term power enhancement using surface modified anodes with activated carbon in ceramic microbial fuel cells Image 1 Highlights: Activated carbon modified anodes outperformed unmodified anodes. Activated carbon modification increased the specific surface area. Incisions in modified and unmodified anodes showed increase in power generation. Good strategy for anode packing in miniaturised MFCs and long term stability. MFCs with modified anodes generated clear catholyte from urine through electrofiltration.