An Experimental and Multiphysics Simulations Study of Clostridium carboxidivorans sp. 624 for Acid and Alcohol Production in CO2/H2

Tiong, Y. W.; Yong, A.; Nalaparaju, A.; Nguyen, H.-H.; Koh, L. Q.; Wong, R. J.; Lim, R. T. Y.; Ow, D. S.-W.; Zhang, J.; Nguyen, V. B.; Wong, F. T.; Lim, Y. H.

doi:10.1101/2025.02.24.639814

bioRxiv · 10.1101/2025.02.24.639814

An Experimental and Multiphysics Simulations Study of Clostridium carboxidivorans sp. 624 for Acid and Alcohol Production in CO2/H2

Tiong, Y. W.·Yong, A.·Nalaparaju, A.·Nguyen, H.-H.·Koh, L. Q.·Wong, R. J.·Lim, R. T. Y.·Ow, D. S.-W.·Zhang, J.·Nguyen, V. B.·Wong, F. T.·Lim, Y. H.

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Abstract

Biotechnological advances in CO2 utilization through gas fermentation offer a sustainable alternative to energy-intensive chemical processes. This study investigates and optimizes fermentation dynamics of Clostridium carboxidivorans sp. 624 for enhanced production of C2-C6 acids via combined experimental and computational methods. A systematic experimental evaluation of temperature and medium conditions, along with time-course analysis elucidates metabolic pathway regulation. Experimental optimisation, complemented by modelling, identified gas-liquid volumetric ratios VL/VG = 4 as optimal for maximizing longer-chain acids production, attributed to enhanced gas solubility and substrate bioavailability. Additionally, a hybrid model combining dynamic-kinetic model and computational fluid dynamics (CFD) successfully predict product formation. By capturing spatial inhomogeneities in gas-liquid interactions, the model also provides critical insights for optimizing fermentation performance and establishes a framework for improving process design parameters for CO2/H2 fermentation, paving the way for scalable and efficient CO2-based bioprocesses.

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Tiong, Y. W., Yong, A., Nalaparaju, A., Nguyen, H.-H., Koh, L. Q., Wong, R. J., Lim, R. T. Y., Ow, D. S.-W., Zhang, J., Nguyen, V. B., Wong, F. T., Lim, Y. H.. 2025-02-24. An Experimental and Multiphysics Simulations Study of Clostridium carboxidivorans sp. 624 for Acid and Alcohol Production in CO2/H2. https://doi.org/10.1101/2025.02.24.639814

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