Impact of cathodic pH and bioaugmentation on acetate and CH₄ production in a microbial electrosynthesis cell

RSC Advances, Journal Year: 2024, Volume and Issue: 14(32), P. 22962 - 22973

Published: Jan. 1, 2024

This study compares carbon dioxide conversion in carbonate-fed microbial electrosynthesis (MES) cells operated at low (5.3), neutral (7) and high (8) pH levels inoculated either with wild-type or bioaugmented mixed populations.

Language: Английский

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Low electric current in a bioelectrochemical system facilitates ethanol production from CO using CO-enriched mixed culture

Frontiers in Microbiology, Journal Year: 2024, Volume and Issue: 15

Published: Aug. 29, 2024

Fossil resources must be replaced by renewable in production systems to mitigate green-house gas emissions and combat climate change. Electro-fermentation utilizes a bioelectrochemical system (BES) valorize industrial municipal waste. Current electro-fermentation research is mainly focused on microbial electrosynthesis using CO 2 for producing commodity chemicals replacing petroleum-based infrastructures. However, slow rates low titers of metabolites during -based impede its implementation the real application near future. On other hand, highly reactive an abundant feedstock discharged from fossil fuel-based industry. Here, we investigated electro-fermentation, CO-enriched culture. Fresh cow fecal waste was enriched under atmosphere 50% 20% N serial cultivation. The culture dominated Clostridium autoethanogenum (≥89%) showed electro-activity BES reactor with sparging. When included 10 mA applied current, acetate ethanol were produced up 12.9 ± 2.7 mM 1.1 mM, respectively. coulombic efficiency estimated 148% 8% without electron mediator. At 25 mA, faster initial growth but no production, only at 86% 4% efficiency. maximum optical density (OD) reactors 0.29 0.07 0.41 0.03, respectively, whereas it 0.77 0.19 electric current. These results show that current can alternative way valorizing system.

Language: Английский

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Trace metals from microbial growth media form in situ electro-catalysts

Electrochimica Acta, Journal Year: 2023, Volume and Issue: 462, P. 142722 - 142722

Published: June 10, 2023

Most microbial electrosynthesis systems depend heavily on the availability of hydrogen as electron carrier. To improve in processes, situ production is required with a catalyst that compatible under conditions (near-neutral pH, mesophilic temperature, aquous electrolyte). Here, we demonstrate use trace metal compounds from medium evolution reaction (HER) electro-catalyst conditions. Concentrated mixtures (10 vol%) present (trace mix medium; containing Co, Cu, Fe, Mn, Mo, Ni and Zn salts ethylenediaminetetraacetic acid (EDTA)) were added to electrochemical reactors (controlled at -1.06 V vs Ag/AgCl flushed CO2/N2). After addition concentrated mix, cathodic current increased up 15 times high recovery into (70-100%). The formed HER performance was also measured growth (with ammonium 0.1 vol% mix), showing similar rates compared medium. Further identification active within emphasized role Cu Mo showed same all previously mentioned compounds. Moreover, without EDTA highest (7 higher -240 A/m2 or -80 kA/m3), decreased overpotential (55 mV -10 A/m2) exchange density (1.36 mA/m2). Integration discovered biological will allow bio-electrochemical fermentation systems.

Language: Английский

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Electrobiocorrosion by Microbes without Outer-Surface Cytochromes

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: July 26, 2023

Abstract Anaerobic microbial corrosion of iron-containing metals causes extensive economic damage. Some microbes are capable direct metal-to-microbe electron transfer (electrobiocorrosion), but the prevalence electrobiocorrosion among diverse methanogens and acetogens is poorly understood because a lack tools for their genetic manipulation. Previous studies have suggested that respiration with 316L stainless steel as donor indicative because, unlike pure Fe 0 , does not abiotically generate H 2 an intermediary carrier. Here we report all ( Methanosarcina vacuolata Methanothrix soehngenii Methanobacterium strain IM1) Sporomusa ovata Clostridium ljungdahlii ) evaluated respired donor, only M. Mx S. were electrobiocorrosion. The electrobiocorrosive required acetate additional energy source in order to produce methane from steel. Co-cultures Mx. demonstrated how can provide during corrosion. Not was IM1 electrobiocorrosion, it also did accept electrons Geobacter metallireducens effective electron- donating partner interspecies directly . finding despite outer-surface c -type cytochromes previously found be important other microbes, demonstrates there multiple strategies making electrical contact Impact Statement Understanding anaerobic receive likely lead novel mitigating metals, which has enormous impact. Electrobiocorrosion, relatively recently recognized mechanism. It cultures when oxidation inhibited by deletion genes known involved forms extracellular exchange. However, many obvious connections difficult genetically manipulate. study reported here provides alternative approach evaluating whether require results indicate IM1, electrobiocorrosive, contrast previous speculation. some without do appear suggesting this mechanism may more widespread than thought.

Language: Английский

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ZnMo-MOF as anti-CO hydrogen electrocatalyst enhance microbial electrosynthesis for CO/CO2 conversion

Chemosphere, Journal Year: 2024, Volume and Issue: 358, P. 142157 - 142157

Published: April 26, 2024

Language: Английский

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