Technological progress and readiness level of microbial electrosynthesis and electrofermentation for carbon dioxide and organic wastes valorization

Inorganic Carbon Assimilation and Electrosynthesis of Platform Chemicals in Bioelectrochemical Systems (BESs) Inoculated with Clostridium saccharoperbutylacetonicum N1-H4

“…Under an energy utilization perspective, the use of pre-constituted bioelectrodes led to a reduction in the overall energy required to produce acetate 4.8 Wh mol −1 in MEC similarly to what was reported by Bajracharya et al (2015) [ 28 ] and Noori et al (2021) [ 17 ]. Undoubtedly, the preparation and acclimatization of the biocathode prior to their use in BESs overcome some limitations in MECs performance, linked to factors such as pH and electrostatic repulsion among cathode and bacterial surfaces (both with negative charges), negatively affecting biofilm formation and metabolism of acetogenic bacteria at the cathode [ 47 ], besides taking to a reduction in the overall energy demand for both direct CO 2 capture and acetate biosynthesis. If we consider that one of the factors that might limit the future development of MET is the energy demand for “driving” the processes at the biocathodes, our results, if further confirmed, might open new possibilities for future practical exploitation of BESs [ 48 ].…”

Microbial electrosynthesis: carbonaceous electrode materials for CO2 conversion

“…1. [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] Although there is an evident lack of a techno-economically driven roadmap for validating and demonstrating the technology on a large scale, MES has received great attention in laboratory-scale research. 26 Recently, much research has focused on engineering cost-effective electrode materials and the biotechnological significance of microbial CO 2 fixation, along with the conversion of precursors to commercial chemicals.…”

Tandem Acidic CO2 Electrolysis Coupled with Syngas Fermentation: A Two-Stage Process for Producing Medium-Chain Fatty Acids

“…5−7 In the past decade, numerous projects focusing on MES at a high technology readiness level (TRL) have been established. 8 However, owing to the limited characteristic density of bacteria and its electron consumption rate, conventional biofilm-based MES has yielded current densities 1−2 orders of magnitude lower than those achieved in industrial electrochemical production. 9,10 Consequently, a hybrid process involving tandem CO 2 electrolysis with fermentation was proposed, incorporating electrocatalysts to enhance CO 2 reduction rates.…”