Identification of removal principles and involved bacteria in microbial fuel cells for sulfide removal and electricity generation

• Sulfide and organics removals with electricity generation are achieved in MFCs.
• Electrochemical and biological oxidations are the main effects.
• The exoelectrogenic and sulfur-related bacteria are found on the anode surface.
• They are present in greater abundance than those in MFCs fed with only sulfide.

Simultaneous sulfide and organics removals with electricity generation can be achieved in microbial fuel cells (MFCs). In present research, principles of sulfide removal as well as the involved bacteria in the MFCs with sulfide and glucose as the complex substrate are investigated. Results indicated that electrochemical and biological oxidations are the main effects for sulfide removal. Community analysis shows a great diversity of bacteria on the anode surface, including the exoelectrogenic bacteria and sulfur-related bacteria. They are present in greater abundance than those in the MFCs fed with only sulfide and responsible for the effective electricity generation and sulfide oxidation in our proposed MFCs. The results are conducive to reveal the interactions between the pollutants and microbes in aspects of pollutants removals and energy recovery in the MFCs for sulfide removal.