Iron-based technology for galvanic biodenitrification and galvanic-Fenton process – IRONTECH

Human activities can be the source of groundwater or surface water pollution. For example, nitrate (NO3-) pollution, widely used in agriculture as a source of nitrogen, is closely linked to the appearance of "green tides" on the French coasts. IRONTECH develops an electrically self-powered strategy to regulate surface water pollution in order to reduce nitrate and organic matter (OM) concentrations, which can be a source of uncontrolled algae growth in aquatic environments.
Electroactive bacteria, living and renewable catalysts, will be immobilized on the surface of conductive electrodes to promote the elimination of NO3- into nitrogen. The supply of electrons necessary for the reduction of NO3- to these bioelectrodes will be ensured by the oxidation of metallic sacrificial anodes thus making the system autonomous in electrical energy. On the other hand, iron electrodes will also be used to regulate the presence of OM in the media. Associated with abiotic carbon cathodes capable of producing hydrogen peroxide (H2O2), the progressive release of Fe2+ will allow to accomplish the galvano-Fenton process. During the biodenitrification and depollution of the OM, the insoluble metal oxides formed at the anodes will be collected and electrochemically treated to allow their reuse.
In turn, the electrical energy created by these two galvanic systems will be used to power a power management system to optimize the efficiency of the device.
The microbial ecology, the electrocatalytic yields of biodenitrification and OM consumption as well as the precise management of the "passive" power supply of the complete system will be characterized, quantified and valorized.