Bioelectricity generation and anodic decolorization of reactive dyes in H-type microbial fuel cell using Pseudomonas gessardii

Anodic decolorization of reactive dyes like Coomassie Brilliant Blue (CB), a triphenylmethane dye, Reactive Red 120 (RR 120) and Reactive Black 5 (RB 5), azo dyes, was investigated in a 300-ml H-type dual chamber Microbial Fuel Cell (MFC) using monoculture of a novel strain Pseudomonas gessardii DD1. The MFC setups were evaluated for power generation, electrochemical activity, dye decolorizing efficiency, and COD removal efficiency. The study revealed a maximum power density 474.06 mW/m² for RB 5 at 100 ppm concentration with 98.5% dye decolorization, while the maximum COD removal efficiency of 70% ± 2.9 was obtained. Cyclic voltammetry curves indicated the highest peak current of 1.8 mA for MFC operated using RB5. Maximum power density, in case of RR 120 and CB was 262.5 and 225.5 mW/m², with 63 and 65% COD removal, respectively. Efficient power generation and dye removal is seldom reported in the literature, as the electrons generated by exoelectrogens are consumed for dye reduction and subsequent breakdown or decolorization. The findings indicate that the MFC technology can be an easy and economical option for bioelectricity generation using dye-contaminated wastewater with simultaneous detoxification of toxic pollutants and hence sustainable treatment of industrial wastewater.