Biochemical Engineering Journal 121 (2017) 17–24 Contents lists available at ScienceDirect Biochemical Engineering Journal jo ur nal home page: www.elsevier.com/locate/bej Regular article Effect of cathode environment on bioelectricity generation using a novel consortium in anode side of a microbial fuel cell Smita S. Kumar a , Suddhasatwa Basu b,∗ , Narsi R. Bishnoi a a Department of Environmental Science and Engineering, Guru Jambheshwar University of Science and Technology, Hisar 125001, Haryana, India b Department of Chemical Engineering, Indian Institute of Technology Delhi Hauz Khas, New Delhi 110016, India a r t i c l e i n f o Article history: Received 30 June 2016 Received in revised form 18 December 2016 Accepted 26 January 2017 Available online 29 January 2017 Keywords: Microbial fuel cell SRB SOB KMnO4 catholyte pH effect Cell performance Landfill leachate a b s t r a c t In the present study, two novel dominant genera i.e., Advenella kashmirensis and Desulfovibrio aminophilus in consortium, as confirmed by IlluminaMiSeq has been used in the anode side of a microbial fuel cell reactor to find out the influence of cathode environment on cell performance. A model terminal electron acceptor (TEA), KMnO 4 at different pHs has been used in the cathode side. An oxidation peak obtained at −0.478 vs Ag/AgCl (−0.281 V vs SHE) corresponding to S 0 /H 2 S (−0.280 V vs SHE) in cyclic voltammogram confirms the complete mineralization of sulphate to biogenic elemental sulphur in accordance with the microbial community. Higher cathodic pH 10 has a detrimental effect on the cell performance as the power density is reduced to half to that for aqKMnO 4 (pH = 6.86) catholyte. Solution resistance is found to be low for aqKMnO 4 (60 ohm) and high i.e. 124.5 ohm for aqKMnO 4 with pH = 10, which corroborates to highest power density obtained for aqKMnO 4. Buffering of the catholyte provided stability to the system with lowest internal resistance of 40 ohm and comparable performance. The highest current density (25 A/m 3 ) and power density (7.8 W/m 3 ) is obtained with aqueous KMnO 4 at pH 6.86. The developed consortium can be successfully utilized in microbial fuel cells for simultaneous electricity generation and wastewater treatment. © 2017 Elsevier B.V. All rights reserved. 1. Introduction Incorporation of right kind of microbes to obtain high perfor- mance microbial fuel cell (MFC) depends great deal on anodic biocatalysts i.e. the microbial community. MFC produces elec- tricity by the disintegration of organic feeds or through waste water treatment in anodic and cathodic chambers. Sulphate reduc- ing bacteria (SRB) are found to exist ubiquitously in all kinds of habitats including wastewaters streams. Under anaerobic condi- tions, sulphate reducing bacteria acquire energy for metabolism by oxidizing organic compounds and even molecular hydrogen thus reducing sulphate to sulphide. Sulphide thus generated can fur- ther be oxidized to elemental sulfur by sulphide oxidizing bacteria (SOB) [1]. Microbial fuel cell reactors (MFC) have been reported to facilitate simultaneous sulphate reduction and sulphide oxida- tion along with bio-electricity generation with the co-existence of anode respiring and SRB + SOB community [2]. A couple of studies have used SRB + SOB consortia for treatment of sulphate ∗ Corresponding author. E-mail addresses: sbasu@iitd.ac.in, drsbasu@gmail.com (S. Basu). laden wastewaters [2,3]. Desulfovibrio aminophilus is an amino acid degrading SRB whereas Advenella kashmirensis is chemoau- totrophic SOB [4,5]. None of the MFC studies so far have reported Desulfovibrio aminophilus (SRB) and Advenella kashmirensis (SOB) solely in pure culture or in consortium fed to MFC. There has been scarcity in studies and harnessing the potential of new microbes in MFC. Practical application of MFC technology suffers from a num- ber of constraints [6]. It has often been observed in dual chamber MFCs (DC-MFC) that, with due course of time, anodic chamber becomes acidic due to microbial activity and cathodic chamber becomes alkaline giving rise to a pH gradient. Both acidification of anolyte and alkalinity at catholytes substantially influence power generation [7]. Anolyte pH plays an important role in growth and metabolism of microbes while cathodic reactions are driven by availability of protons. To promote transfer of protons from the anode to cathode, reduce the internal resistance and increase the performance a suitable pH gradient is required between the cathode and anode chambers. Therefore it is important to check performance of DC-MFC in terms of power generation and internal resistance at different pHs. http://dx.doi.org/10.1016/j.bej.2017.01.014 1369-703X/© 2017 Elsevier B.V. All rights reserved.