Stainless steel and carbon brushes as high-performance anodes for energy production and nutrient recovery using the microbial nutrient recovery system

Microbial fuel cell (MFC) technology allows renewable energy production from the decomposition of organic matter present in wastewater. This technology, however, poses challenges that hinder scaling up of its usage in practical implementation. Also, resource recovery from the available waste sources is attracting attention due to the immense amount of valuable nutrients present in the wastewater. Herein, the present study focuses on investigating high-performance anodes, that is, using a stainless-steel brush (SSB) and carbon brush (CB) to accommodate the MFC in terms of energy production, leading to transformation into a microbial nutrient recovery system (MNRS) for nutrients’ recovery from wastewater. The present novel SSB anode system generated a stable voltage of ∼0.4V and a maximum power density of ∼400 mW/m² whereas CB anode system produced the voltage and maximum power density of ∼0.5 V and ∼800 mW/m², respectively. Besides, using the MNRS process, recovery of nutrients in terms of PO₄³⁻ (80–83.4% for CB-MNRS and 60–69.5% for SSB-MNRS when using feed PO₄³⁻ concentration of 10–20 ppm) and NH₄⁺ (63–80.64% for the CB-MNRS and 52–70% for the SSB-MNRS when using feed NH₄⁺ with a concentration of 10–20 ppm) was achieved.