Article

Mixotrophic operation of photo-bioelectrocatalytic fuel cell under anoxygenic microenvironment enhances the light dependent bioelectrogenic activity

Bioengineering and Environmental Centre, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 607, India.
Bioresource Technology (Impact Factor: 4.49). 04/2012; 109:46-56. DOI: 10.1016/j.biortech.2011.12.135
Source: PubMed

ABSTRACT

Electrogenic activity of photo-bioelectrocatalytic /photo-biological fuel cell (PhFC) was evaluated in a mixotrophic mode under anoxygenic microenvironment using photosynthetic consortia as biocatalyst. An acetate rich wastewater was used as anolyte for harnessing energy along with additional treatment. Mixotrophic operation facilitated good electrogenic activity and wastewater treatment associated with biomass growth. PhFC operation documented feasible microenvironment for the growth of photosynthetic bacteria compared to algae which was supported by pigment (total chlorophyll and bacteriochlorophyll) and diversity analysis. Pigment data also illustrated the association between bacterial and algal species. The synergistic interaction between anoxygenic and oxygenic photosynthesis was found to be suitable for PhFC operation. Light dependent deposition of electrons at electrode was relatively higher compared to dark dependent electron deposition under anoxygenic condition. PhFC documented for good volatile fatty acids removal by utilizing them as electron donor. Bioelectrochemical behavior of PhFC was evaluated by voltammetric and chronoamperometry analysis.

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    • "larger surface area and/or catalyst on the cathode surface). In future reported by Chandra et al. [59], who used mixed photosynthetic consortia on plain graphite plates; however, regular acetate feeding was necessary to retain such high power generation, and the anode was kept under anaerobic conditions, requiring N 2 gas sparging. We therefore decided to use the ZACC + Nafion 115 cathodes further and to use them in mediator-free p-MFCs. "
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