Resistance assessment of microbial electrosynthesis for biochemical production to changes in delivery methods and CO2 flow rates. (January 2021)

• Record Type: Journal Article
• Authors: Bian, Bin; Xu, Jiajie; Katuri, Krishna P.; Saikaly, Pascal E.
• Is Part Of: Bioresource technology. Volume 319(2021)
• Publication Date: 2021-01
• Subjects: Microbial electrosynthesis -- CO2 flow fluctuation -- Biochemical production -- CO2 valorization -- Carbon capture and utilization; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2020.124177
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: The robustness of MES to CO2 flow rate fluctuation was studied for the first time. Methane and acetate production rates were improved with increasing CO2 flow rates. Microbial community exhibited high resistance to changes in CO2 flow rates. Enhanced biochemical production was achieved by minimizing CO2 diffusion distance. Hydrogen mediates electron transfer for methane and acetate production in MES. Abstract: Microbial electrosynthesis (MES) for CO2 valorization could be influenced by fluctuations in CO2 mass transfer and flow rates. In this study, we developed an efficient method for CO2 delivery to cathodic biofilm by directly sparging CO2 through the pores of ceramic hollow fiber wrapped with Ni-foam/carbon nanotube electrode, and obtained 45% and 77% higher acetate and methane production, respectively. This was followed by the MES stability test in response to fluctuations in CO2 flow rates varying from 0.3 ml/min to 10 ml/min. The biochemical production exhibited an increasing trend with CO2 flow rates, achieving higher acetate (47.0 ± 18.4 mmol/m 2 /day) and methane (240.0 ± 32.2 mmol/m 2 /day) generation at 10 ml/min with over 90% coulombic efficiency. The biofilm and suspended biomass, however, showed high resistance to CO2 flow fluctuations with Methanobacterium and Acetobacterium accounting for 80% of the total microbial community, which suggests the robustness of MES for onsite carbon conversion.