Abstract
In this study, an enzymatic pathway has been developed to replicate the Calvin Cycle by creating the individual steps of the carbon cycle in a bioreactor. The technology known as “artificial photosynthesis” converts CO2 emissions into a variety of intermediates that serve as precursors to high-value products. CO2, light, water, and electricity were used as feedstock. An electrochemical reactor was also studied for the regeneration of active NADH operating at constant electrode potential. Initially, a batch electrochemical reactor containing 80 mL of 0.2 mM NAD+ in Tris-buffer (pH 7.40) was used to evaluate the electrode material operating at normal temperature and pressure. The results showed that the cathode is highly electrocatalytically efficient and selective to regenerate 97.45±0.8% of NADH from NAD+ at electrode potential of -2.3 V vs. mercury standard electrode (MSE). The NADH regeneration system was then integrated with ATP regeneration system and bioreactor containing Ribulose bisphosphate carboxylase/oxygenase (RuBisCO). NADH was regenerated successfully during the process electrochemically and then was used by the enzymatic reaction to produce triose phosphate and 3-Phosphoglycerate (3GPA).
Highlights
Economic growth along with high density infrastructural and transportation development is mainly responsible for rapid energy demand that resulted in an increased emission of carbon dioxide (CO2)
Since impurities on the electrode surface greatly affect its performance, glassy carbon (GC) electrode was electrochemically cleaned in 0.5 M H2SO4 (Fisher Scientific 351293) by cyclic voltammetry between –1.8 and 1.8 V at a scan rate of 100 mV s–1, for 50 cycles using the same electrochemical reactor
To minimize the interference of hydrogen evolution reaction (HER) and its effect on NAD+ reduction reaction, Glassy Carbon was used as a working electrode due to its high hydrogen reduction overpotential, in addition to low porosity and comparatively better electrical conductivity [45]
Summary
Economic growth along with high density infrastructural and transportation development is mainly responsible for rapid energy demand that resulted in an increased emission of carbon dioxide (CO2). CO2 is the primary anthropogenic greenhouse gas (GHG) mainly responsible for global warming due to the burning of fossil fuels (coal, hydrocarbons, peat) for energy [1,2,3]. It is desired to develop green and sustainable technology to convert CO2 into valuable materials for carbon capture and sequestration (CCS) technology and reduce the burden on greenhouse gas emissions. The developed routes for CO2 reduction are the reduction at the source (i.e. reduced use of fossil fuels), sequestration and the chemical conversion [7]. Instead CO2 upcycling offers a pathway towards more sustainable processes [5, 8,9,10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
