Comparing the short and long term stability of biodegradable, ceramic and cation exchange membranes in microbial fuel cells

• Published in: Bioresource technology 2013-11, Vol.148, p.480-486
• Main Authors: Winfield, Jonathan, Chambers, Lily D., Rossiter, Jonathan, Ieropoulos, Ioannis
• Format: Article
• Language: English
• Subjects: Bags; Biochemical fuel cells; Biodegradation; Biodegradation, Environmental; Bioelectric Energy Sources; Biofuel production; Biological and medical sciences; Biotechnology; Cation Exchange Resins - chemistry; Cation exchanging; Ceramic; Ceramics; Ceramics - chemistry; Electric Impedance; Energy; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; Ion exchange materials; Membranes; Membranes, Artificial; Microbial fuel cell; Microorganisms; Power overshoot; Proton exchange membrane; Stability; Time Factors
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2013.08.163

•Novel biodegradable bag (BioBag) successfully worked as an MFC membrane.•BioBag degraded but with stable performance, pointing to missions with expiry dates.•Ceramic membrane more stable short-term and equal to CEM over long-term.•CEM exhibited power overshoot and hysteresis during bi-directional polarisation.•The anolyte of BioBag and ceramic MFCs was less prone to acidification. The long and short-term stability of two porous dependent ion exchange materials; starch-based compostable bags (BioBag) and ceramic, were compared to commercially available cation exchange membrane (CEM) in microbial fuel cells. Using bi-directional polarisation methods, CEM exhibited power overshoot during the forward sweep followed by significant power decline over the reverse sweep (38%). The porous membranes displayed no power overshoot with comparably smaller drops in power during the reverse sweep (ceramic 8%, BioBag 5.5%). The total internal resistance at maximum power increased by 64% for CEM compared to 4% (ceramic) and 6% (BioBag). Under fixed external resistive loads, CEM exhibited steeper pH reductions than the porous membranes. Despite its limited lifetime, the BioBag proved an efficient material for a stable microbial environment until failing after 8 months, due to natural degradation. These findings highlight porous separators as ideal candidates for advancing MFC technology in terms of cost and operation stability.