CO2-refinery through microbial electrosynthesis (MES): A concise review on design, operation, biocatalysts and perspectives

Microbial electrosynthesis cells (MES) are devices with demonstrated capability to treat CO2-containing gaseous streams and alongside, generate certain valuable chemical products, particularly methane gas, carboxylic acids, alcohols, etc. Although there are many varieties of MES with their own individual characteristics, all systems have a lot in common, starting from their design and operational features to the underlying microbiological phenomena. With the support of literature publications and related numerical data, this paper reviews and analyses the most important features of MES to identify general tendencies and practical recommendations pertaining to their design (electrodes, membranes), operation (cathode potential, CO2 feeding, temperature, pH) and biocatalysts ensuring an enhanced performance. As a result, several key-issues are provided to (i) successfully implement MES setups as well as to (ii) outline the perspectives of the technology towards the further promotion and development of this CO2-refinery process