title: A single-chamber microbial fuel cell without an air cathode.
abstract: Microbial fuel cells (MFCs) represent a novel technology for wastewater treatment with electricity production. Electricity generation with simultaneous nitrate reduction in a single-chamber MFC without air cathode was studied, using glucose (1 mM) as the carbon source and nitrate (1 mM) as the final electron acceptor employed by Bacillus subtilis under anaerobic conditions. Increasing current as a function of decreased nitrate concentration and an increase in biomass were observed with a maximum current of 0.4 mA obtained at an external resistance (R(ext)) of 1 KΩ without a platinum catalyst of air cathode. A decreased current with complete nitrate reduction, with further recovery of the current immediately after nitrate addition, indicated the dependence of B. subtilis on nitrate as an electron acceptor to efficiently produce electricity. A power density of 0.0019 mW/cm(2) was achieved at an R(ext) of 220 Ω. Cyclic voltammograms (CV) showed direct electron transfer with the involvement of mediators in the MFC. The low coulombic efficiency (CE) of 11% was mainly attributed to glucose fermentation. These results demonstrated that electricity generation is possible from wastewater containing nitrate, and this represents an alternative technology for the cost-effective and environmentally benign treatment of wastewater.
authors.affiliation: Department of Life Science, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi, 621, Taiwan.
authors.forename: Vanita Roshan
authors.initials: VR
authors.lastname: Nimje
authors.affiliation: Department of Biotechnology, National Kaohsiung Normal University, No. 62, Shenjhong Rd., Yanchao Township, Kaohsiung County, 82444, Taiwan.
authors.forename: Chien-Cheng
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Department of Life Science, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi, 621, Taiwan.
authors.forename: Hau-Ren
authors.initials: HR
authors.lastname: Chen
authors.affiliation: Department of Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621, Taiwan.|Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK.
authors.forename: Chien-Yen
authors.initials: CY
authors.lastname: Chen
authors.affiliation: Department of Life Science, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi, 621, Taiwan.
authors.forename: Min-Jen
authors.initials: MJ
authors.lastname: Tseng
authors.affiliation: Department of Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621, Taiwan.
authors.forename: Kai-Chien
authors.initials: KC
authors.lastname: Cheng
authors.affiliation: Department of Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621, Taiwan.
authors.forename: Ruey-Chyuan
authors.initials: RC
authors.lastname: Shih
authors.affiliation: Department of Earth and Environmental Sciences, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621, Taiwan.
authors.forename: Young-Fo
authors.initials: YF
authors.lastname: Chang
mesh_terms: D001412:Bacillus subtilis / Q000378:metabolism*; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D018533:Biomass; D004560:Electricity; D004566:Electrodes; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism*; D018505:Waste Management / Q000379:methods; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification / Q000379:methods
chemical_list: D005947:Glucose; D009566:Nitrates; D062065:Wastewater