In a study published in RSC Sustainability, Sofía Antic Gorrazzi and colleagues explored biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More as a sustainable alternative to graphite in microbial electrochemical technologies (METs). Biochar, derived from biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More like pruning residues, presents a biocompatible, low-cost, and environmentally friendly electrode material. The key finding of their research is that biochar produced at lower temperatures (600°C) can achieve about half the electric current generated by high-temperature biochar or graphite electrodes.  

The authors emphasize the importance of this result by highlighting that the production of low-temperature biochar leads to substantially lower carbon emissions and energy consumption than graphite production. In fact, the biochar electrodes produced at 600°C have a net positive carbon footprint and lower production costs, marking a significant advantage for environmental sustainability.  

The study highlights the potential of biochar as a more sustainable substitute for graphite in microbial electrochemical technologies. While graphite is currently the most commonly used electrode material in METs, its production involves high energy inputs and carbon emissions. Biochar, on the other hand, can be produced from various biomass feedstocks, including pruning residues, and its production can even contribute to carbon sequestration.  

Despite the promising results, the authors also point out that further research is needed. There is a need to optimize biochar’s conductivity and mechanical performance to support its use in large-scale METs. Overcoming these challenges could significantly enhance the sustainability and broader application of microbial electrochemical technologies.  

SOURCE: Antic Gorrazzi, S., Massazza, D., Pedetta, A., Silva, L., Prados, B., Fouga, G., & Bonanni, S. (2023). Biochar as a substitute for graphite in microbial electrochemical technologies. RSC Sustainability, 1, 1200-1210