Carbon Aerogel Coated Air-Cathode Bioelectrochemical System for Simultaneous Nitrogen and Phosphorus Removal

Modern bio-electrochemical technologies can convert the energy stored in the chemical bonds of biodegradable organic materials into renewable electrical bioenergy through the catalytic reactions of the microorganisms while treating the wastewaters. The present research has been conducted to study the efficiency of the single-chamber bioelectrochemical system with carbon aerogel catalyst as a new, simple, and inexpensive approach to remove and recover the valuable but polluting nutrients (nitrogen and phosphorus) from municipal wastewaters and also determine the optimal conditions to scale up the system in countries with hot, dry climates. In the present study, the bacterial consortium was isolated from the sediments of local lagoons, and municipal wastewater was used as the substrate. During the six months of cell operation, the effluent of BES showed a 54.9% decrease in nitrate concentration and a 59.8% decrease in total N and 90% of phosphate removed from wastewater, the total nitrogen, and total phosphate concentration in effluent were 28.9 ± 24.3 mg/L. and 13 ± 46.8 mg/L, respectively. The maximum removal of COD was 80%, and the maximum power density was 1.82mW/m2. Carbon aerogel, as a novel material with suitable absorbance and resistance to oxidation by urban wastewater pH can be coated on electrodes to facilitate the Oxidation Reduction reactions and electricity transmission.