A Comprehensive Modeling Analysis of Formate‐Mediated Microbial Electrosynthesis. Issue 1 (20th October 2020)

• Record Type: Journal Article
• Authors: Abel, Anthony J.; Clark, Douglas S.
• Is Part Of: ChemSusChem. Volume 14:Issue 1(2021)
• Page Start: 344
• Page End: 355
• Publication Date: 2020-10-20
• Subjects: biosynthesis -- CO2 reduction -- electrochemistry -- formate -- multiphysics modeling; Green chemistry -- Periodicals; Sustainable engineering -- Periodicals; Chemistry -- Periodicals; Chemical engineering -- Periodicals; 660
• DOI: 10.1002/cssc.202002079
• Languages: English
• ISSNs: 1864-5631

Abstract

Abstract: Mediated microbial electrosynthesis (MES) represents a promising strategy for the capture and conversion of CO2 into carbon‐based products. We describe the development and application of a comprehensive multiphysics model to analyze a formate‐mediated MES reactor. The model shows that this system can achieve a biomass productivity of ∼1.7 g L −1 h −1 but is limited by a competitive trade‐off between O2 gas/liquid mass transfer and CO2 transport to the cathode. Synthetic metabolic strategies are evaluated for formatotrophic growth, which can enable an energy efficiency of ∼21 %, a 30 % improvement over the Calvin cycle. However, carbon utilization efficiency is only ∼10 % in the best cases due to a futile CO2 cycle, so gas recycling will be necessary for greater efficiency. Finally, separating electrochemical and microbial processes into separate reactors enables a higher biomass productivity of ∼2.4 g L −1 h −1 . The mediated MES model and analysis presented here can guide process design for conversion of CO2 into renewable chemical feedstocks. Abstract : Model‐driven insight : Coupling electrochemical CO2 reduction to formate and microbial catalysis is a promising platform for sustainable chemical production. A comprehensive model capturing mass transport; electrochemical, acid/base, and microbial reaction kinetics and thermodynamics; temperature effects; and gas/liquid mass transfer was developed, revealing insights into performance limits for this system.