Enzymatic electrosynthesis of formate through CO2 sequestration/reduction in a bioelectrochemical system (BES)

Author:

Sandipam Srikanth, Miranda Maesen, Xochitl Dominguez-Benetton, Karolien Vanbroekhoven, Deepak Pant
Abstract:

Bioelectrochemical system (BES) was operated using the enzyme formate dehydrogenase as catalyst at cathode in its free form for the reduction of CO₂ into formic acid.

Electrosynthesis of formic acid was higher at an operational voltage of −1 V vs. Ag/AgCl (9.37 mg L⁻¹ CO₂) compared to operation at −0.8 V (4.73 mg L⁻¹ CO₂) which was strongly supported by the reduction catalytic current. Voltammograms also depicted a reversible redox peak throughout operation at −1 V, indicating NAD⁺ recycling for proton transfer from the source to CO₂. Saturation of the product was observed after 45 min of enzyme addition and then reversibility commenced, depicting a lower and stable formic acid concentration throughout the subsequent time of operation.

Stability of the enzyme activity after immobilization on the electrode and product yield will be studied further.
Journal:

Bioresource technology
Publisher:

Elsevier
Volume (Issue):

165
Page:

350-354
Sector:

Sustainability Energy Storage
Publication Type:

Research Article

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