Complex waste acclimatized mixed culture enhances bioelectricity generation and tannery wastewater treatment in microbial fuel cells

Microbial fuel cell (MFC) are bio-electrochemical systems that produce electricity generally coupled with organics removal from wastewater using bacteria as biocatalysts. While recent studies revealed that wastewater-specific efficient bacterial consortiums are crucial for the current generation and effective wastewater treatment, the potential of complex wastes acclimatized cultures has less often investigated in MFC. In this work, a dual-chamber MFC system was utilized for electricity generation and complex tannery wastewater treatment simultaneously using mixed microbial consortia from the tannery waste vicinity. Since behavioral and/or biochemical traits of acclimatized culture stimulate biodegradation of organic chemicals, much better MFC performance was achieved in comparison to non-acclimatized cultures. A maximum power density of 223 ± 11 and 143 ± 6 mW m −2 was achieved with tannery wastewater (1,000 mg L −1 COD) as electron donors’ source with acclimatized and non-acclimatized cultures, respectively. A significant reduction in power generation in the absence of nutrients revealed their importance for electroactive bacteria. In terms of treatment efficiency, acclimatized culture MFC resulted in ~ 1.5-fold higher COD removal than non-acclimatized culture MFC. Further, a reduction of 13% COD removal was observed in an open circuit in comparison to MFC mode suggests wastewater degradation was enhanced with extracellular electron transfer. This study established that MFC could be utilized for achieving efficient bioelectricity production and complex wastewaters treatment simultaneously using wastewater-specific acclimatized microbial cultures. Graphical abstract