Decolorization of Azo Dye AR27 and Bioelectricity Generation in Microbial Fuel Cell

Abstract

In this study, we investigate the ability of the bacterial isolates from an Iraqi oil reservoir, namely POS and PCO Oil to decolorize commercially used model azo dye Acid Red-27(AR-27). The effects of inoculation volume and glycerol concentrations were optimized to develop an economically feasible decolourization process. The isolates were able to decolourize azo dye (AR27) at the highest decolorization efficiency of 98% in 10 mL bacterial solution consisted of POS and PCO Oil and in the presence of 6.34 g/L glycerol. An optimized MFC using this bacterial consortium (POS + PCO Oil) and graphite rod electrodes produced a maximum open circuit voltage (OCV) of 175 mV, in the presence of potassium ferricyanide as the electron acceptor at the cathode. The maximum current density of 1.7 ?A/cm² and power density of 59.3 ?W/cm² were achieved when an external load of 5 k? was applied. Morphological analysis was performed using Scanning Electron Microscope (SEM) to prove the bacterial attachment onto the anode surface (graphite rod) in the MFC operation. This work proposed that the bacterial strains POS and PCO Oil possess the ability to decolorize Azo dye AR27 and generate electricity in the absence of nitrogen source.