Electrochemical decolorization of methyl orange powered by bioelectricity from single-chamber microbial fuel cells

Baogang Zhang, Zhijun Wang, Xiang Zhou, Chunhong Shi, Huaming Guo, Chuanping Feng

Abstract

Methyl orange (MO), a typical azo dye, is a well-known recalcitrant pollutant in dye wastewater. An aeration electrochemical system with single-chamber microbial fuel cell (MFC) as renewable power sources is proposed for MO decolorization. The enhanced color removal efficiency up to 90.4% within 360 min is observed with voltage across the aeration electrolytic reactor fixed at 700 mV. The results from gas chromatography–mass spectrometry (GC–MS) analysis indicate the destruction of MO, with generation of low molecular weight compounds such as benzene derivatives. Comparison experiments imply the indirect electrochemical oxidation of MO by generated H₂O₂ is mainly responsible for MO decolorization in present study. This work offers a cost-effective electrochemical method for enhancing electrochemical degradation of dyes with bioelectricity generated from MFCs.

Keywords: Microbial fuel cells; Electrochemical; Decolorization; Azo dye; Methyl orange.