A Sustainable Chemicals Manufacturing Paradigm Using CO2 and Renewable H2
Rajesh Reddy Bommareddy,
Yanming Wang,
Nicole Pearcy,
Martin Hayes,
Edward Lester,
Nigel P. Minton,
Alex V. Conradie
Affiliations
Rajesh Reddy Bommareddy
BBSRC/EPSRC Synthetic Biology Research Centre, Biodiscovery Institute (BDI), School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK; Corresponding author
Yanming Wang
BBSRC/EPSRC Synthetic Biology Research Centre, Biodiscovery Institute (BDI), School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
Nicole Pearcy
BBSRC/EPSRC Synthetic Biology Research Centre, Biodiscovery Institute (BDI), School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
Martin Hayes
Johnson Matthey Technology Centre, 28 Cambridge Science Park, Milton Road, Cambridge CB4 0 FP, UK
Edward Lester
Department of Chemical & Environmental Engineering, University of Nottingham, Nottingham NG7 2RD, UK
Nigel P. Minton
BBSRC/EPSRC Synthetic Biology Research Centre, Biodiscovery Institute (BDI), School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
Alex V. Conradie
Department of Chemical & Environmental Engineering, University of Nottingham, Nottingham NG7 2RD, UK; Corresponding author
Summary: The chemical industry must decarbonize to align with UN Sustainable Development Goals. A shift toward circular economies makes CO2 an attractive feedstock for producing chemicals, provided renewable H2 is available through technologies such as supercritical water (scH2O) gasification. Furthermore, high carbon and energy efficiency is paramount to favorable techno-economics, which poses a challenge to chemo-catalysis. This study demonstrates continuous gas fermentation of CO2 and H2 by the cell factory, Cupriavidus necator, to (R,R)-2,3-butanediol and isopropanol as case studies. Although a high carbon efficiency of 0.75 [(C-mol product)/(C-mol CO2)] is exemplified, the poor energy efficiency of biological CO2 fixation requires ∼8 [(mol H2)/(mol CO2)], which is techno-economically infeasible for producing commodity chemicals. Heat integration between exothermic gas fermentation and endothermic scH2O gasification overcomes this energy inefficiency. This study unlocks the promise of sustainable manufacturing using renewable feedstocks by combining the carbon efficiency of bio-catalysis with energy efficiency enforced through process engineering.
