Microbial electrosynthesis from CO2: Challenges, opportunities and perspectives in the context of circular bioeconomy

• Published in: Bioresource technology Vol. 302; p. 122863
• Main Authors: Bian, Bin, Bajracharya, Suman, Xu, Jiajie, Pant, Deepak, Saikaly, Pascal E.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2020
• Subjects: anodes; bioeconomics; carbon dioxide; cathodes; Circular bioeconomy; circular economy; CO2 reduction; cost effectiveness; Electrode materials; electrosynthesis; energy; energy costs; Microbial electrosynthesis; Oxygen evolution reaction; technology; Microbial electrosynthesis; Electrode materials; Oxygen evolution reaction; CO2 reduction; Circular bioeconomy
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2020.122863

[Display omitted] •MES cathode for better bacterial growth and CO2 delivery is reviewed.•Strategies are provided for energy-efficient anodic electron generation.•MES chain-elongation suitable for high-value product formation and extraction.•MES integrated with other bioprocesses can be promising to sustain circular economy. Recycling CO2 into organic products through microbial electrosynthesis (MES) is attractive from the perspective of circular bioeconomy. However, several challenges need to be addressed before scaling-up MES systems. In this review, recent advances in electrode materials, microbe-catalyzed CO2 reduction and MES energy consumption are discussed in detail. Anode materials are briefly reviewed first, with several strategies proposed to reduce the energy input for electron generation and enhance MES bioeconomy. This was followed by discussions on MES cathode materials and configurations for enhanced chemolithoautotroph growth and CO2 reduction. Various chemolithoautotrophs, effective for CO2 reduction and diverse bioproduct formation, on MES cathode were also discussed. Finally, research efforts on developing cost-effective process for bioproduct extraction from MES are presented. Future perspectives to improve product formation and reduce energy cost are discussed to realize the application of the MES as a chemical production platform in the context of building a circular economy.