title: Redox mediator enhanced simultaneous decolorization of azo dye and bioelectricity generation in air-cathode microbial fuel cell.
abstract: Enhanced simultaneous decolorization of Congo red and bioelectricity generation with anthraquinone-2,6-disulphonic disodium salt (AQDS), riboflavin (RF) and humic acid (HA) as mediators in air-cathode microbial fuel cell (MFC) was demonstrated. Compared with mediator-free MFC, the MFC with added 0.005 mM AQDS, 0.005 mM RF or 1g/L HA showed 36%, 26% and 15% increase in maximum power density along with 394%, 450%, and 258% increases in decolorization rates of Congo red, respectively. Addition of mediators at higher concentration further increased power and Congo red decolorization but the increases were not proportional to the rise in mediator concentration. Based on decreases of anode charge transfer resistance and increases of Congo red decolorization, the mediators kinetically promote the extracellular electron transfer between bacteria, anode and Congo red. Microbial analysis showed that addition of mediators changed the composition of anodic microbial community and stimulated the growth of species belonging to Chlorobi, Endomicrobia and Firmicutes.
authors.affiliation: State Key Lab of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640, China. sunjian472@163.com
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.forename: Wanjun
authors.initials: W
authors.lastname: Li
authors.forename: Youming
authors.initials: Y
authors.lastname: Li
authors.forename: Yongyou
authors.initials: Y
authors.lastname: Hu
authors.forename: Yaping
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D001391:Azo Compounds / Q000378:metabolism*; D001419:Bacteria / Q000737:chemistry / Q000378:metabolism; D001483:Base Sequence; D001674:Bioelectric Energy Sources; D003116:Color; D004396:Coloring Agents / Q000378:metabolism*; D017931:DNA Primers; D004566:Electrodes; D004579:Electron Transport; D010084:Oxidation-Reduction; D016133:Polymerase Chain Reaction
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D017931:DNA Primers
keywords: Azo dye; Decolorization; Electricity generation; Electron transfer; Microbial fuel cell