Yu_d0fd00132e.pdf (1022.68 kB)
Download file

Enhanced bio-production from CO2 by microbial electrosynthesis (MES) with continuous operational mode

Download (1022.68 kB)
journal contribution
posted on 08.02.2021, 14:56 by Paniz Izadi, Jean-Marie Fontmorin, Swee Su Lim, Ian Head, Eileen YuEileen Yu

Technologies able to convert CO2 to various feedstocks for fuels and chemicals are emerging due to the urge of reducing greenhouse gas emissions and de-fossilizing chemical production. Microbial electrosynthesis (MES) has been shown a promising technique to synthesize organic products particularly acetate using microorganisms and electrons. However, the efficiency of the system is low. In this study, we demonstrated the simple yet efficient strategy in enhancing the efficiency of MES by applying continuous feeding regime. Compared to the fed-batch system, continuous operational mode provided better control of pH and constant medium refreshment, resulting in higher acetate production rate and more diverse bio-products, when the cathodic potential of -1.0 V Ag/AgCl and dissolved CO2 were provided. It was observed that hydraulic retention time (HRT) had a direct effect on the pattern of production, acetate production rate and coulombic efficiency. At HRT of 3 days, pH was around 5.2 and acetate was the dominant product with the highest production rate of 651.8 ± 214.2 ppm day-1 and a significant coulombic efficiency of 90%. However at the HRT of 7 days, pH was lower at around 4.5, and lower but stable acetate production rate of 280 ppm day-1 and a maximum coulombic efficiency of 80% was obtained. In addition, more diverse and longer chain products, such as butyrate, isovalerate and caproate, were detected with low concentrations only at the HRT of 7 days. Although microbial community analysis showed the change in the planktonic cells communities after switching the fed-batch mode to continuous feeding regime, Acetobacterium still remained as the responsible bacteria for CO2 reduction to acetate, dominating the cathodic biofilm.

Funding

Liquid Fuel and bioEnergy Supply from CO2 Reduction

Engineering and Physical Sciences Research Council

Find out more...

ISCF Wave 1: North East Centre for Energy Materials

Engineering and Physical Sciences Research Council

Find out more...

Resource recovery from wastewater with Bioelectrochemical Systems

Natural Environment Research Council

Find out more...

NBIC 002POC19034

History

School

  • Aeronautical, Automotive, Chemical and Materials Engineering

Department

  • Chemical Engineering

Published in

Faraday Discussions

Volume

230

Pages

344-359

Publisher

Royal Society of Chemistry (RSC)

Version

VoR (Version of Record)

Publisher statement

This is an Open Access Article. It is published by Royal Society of Chemistry under the Creative Commons Attribution 4.0 Unported Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/

Acceptance date

11/01/2021

Publication date

2021-01-29

Copyright date

2021

ISSN

1359-6640

eISSN

1364-5498

Language

en

Depositor

Deposit date: 8 February 2021

Usage metrics

Categories

Licence

Exports