Bioelectricity Generation and Decolorization of Reactive Blue 221 Using a Modified Cathode Dual-Chamber Microbial Fuel Cell

Abstract

In this study, the simultaneous enzymatic decolorization of reactive blue 221 (RB221) and the performance of different electrode carbon nanotube (CNT)-modified/unmodified carbon graphite cathodes were investigated in a dual-chamber Microbial Fuel Cell (MFC) at a permanent temperature of 25 °C. The maximum power density and maximum voltage increased by approximately 13.6% and 50%, respectively, when using the CNT-modified carbon graphite electrode as the cathode. A suspended laccase enzyme was utilized in the cathode compartment for dye decolorization. In the absence of the dye, laccase caused an increase in power density to about 28%. In addition, this research revealed that an initial dye concentration of 80 mg/L simultaneously resulted in an enzymatic decolorization efficiency of 73.4% in the cathode chamber and 82.3% chemical oxygen demand (COD) removal of sucrose in the anode chamber. Finally, this study substantiates the fact that an MFC equipped with a CNT-modified carbon graphite electrode can be used for bioelectricity generation and effective dye removal.

Key findings

• ▸The CNT-modified carbon graphite electrode increased maximum power density by 13.6% and maximum voltage by 50%.
• ▸The suspended laccase enzyme increased power density by 28% in the absence of the dye.
• ▸The MFC achieved 73.4% enzymatic decolorization efficiency and 82.3% chemical oxygen demand removal at an initial dye concentration of 80 mg/L.

Keywords

Identifiers

DOI

10.3390/w15010101

Journal

Water

Year

2022