title: Microbial fuel cell operation using monoazo and diazo dyes as terminal electron acceptor for simultaneous decolourisation and bioelectricity generation.
abstract: Monoazo and diazo dyes [New coccine (NC), Acid orange 7 (AO7), Reactive red 120 (RR120) and Reactive green 19 (RG19)] were employed as electron acceptors in the abiotic cathode of microbial fuel cell. The electrons and protons generated from microbial organic oxidation at the anode which were utilized for electrochemical azo dye reduction at the cathodic chamber was successfully demonstrated. When NC was employed as the electron acceptor, the chemical oxygen demand (COD) removal and dye decolourisation efficiencies obtained at the anodic and cathodic chamber were 73±3% and 95.1±1.1%, respectively. This study demonstrated that the decolourisation rates of monoazo dyes were ∼50% higher than diazo dyes. The maximum power density in relation to NC decolourisation was 20.64mW/m2, corresponding to current density of 120.24mA/m2. The decolourisation rate and power output of different azo dyes were in the order of NC>AO7>RR120>RG19. The findings revealed that the structure of dye influenced the decolourisation and power performance of MFC. Azo dye with electron-withdrawing group at para substituent to azo bond would draw electrons from azo bond; hence the azo dye became more electrophilic and more favourable for dye reduction.
authors.affiliation: Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia.
authors.forename: Yoong-Sin
authors.initials: YS
authors.lastname: Oon
authors.affiliation: Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia. Electronic address: ongsoonan@yahoo.com.
authors.forename: Soon-An
authors.initials: SA
authors.lastname: Ong
authors.affiliation: School of Materials Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia.
authors.forename: Li-Ngee
authors.initials: LN
authors.lastname: Ho
authors.affiliation: Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia.
authors.forename: Yee-Shian
authors.initials: YS
authors.lastname: Wong
authors.affiliation: Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia.
authors.forename: Yoong-Ling
authors.initials: YL
authors.lastname: Oon
authors.affiliation: Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia.
authors.forename: Harvinder Kaur
authors.initials: HK
authors.lastname: Lehl
authors.affiliation: Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia.
authors.forename: Wei-Eng
authors.initials: WE
authors.lastname: Thung
authors.affiliation: School of Materials Engineering, Universiti Malaysia Perlis, 02600, Arau, Perlis, Malaysia.
authors.forename: Noradiba
authors.initials: N
authors.lastname: Nordin
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D001557:Benzenesulfonates / Q000737:chemistry; D001673:Biodegradation, Environmental; D001674:Bioelectric Energy Sources; D057919:Biological Oxygen Demand Analysis; D003116:Color; D004566:Electrodes; D004583:Electrons; D009282:Naphthalenesulfonates / Q000737:chemistry; D016877:Oxidants; D010100:Oxygen / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D014227:Triazines / Q000737:chemistry; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification
chemical_list: D001391:Azo Compounds; D001557:Benzenesulfonates; D009282:Naphthalenesulfonates; D016877:Oxidants; D010100:Oxygen; D014227:Triazines; D062065:Wastewater; C000614522:reactive green 19; C042516:reactive red 120 dye; C014722:2-naphthol orange; C576297:ponceau 4R
keywords: Azo dye; Bioelectricity generation; Decolourisation; Double chambered MFC; Wastewater treatment