Autotrophic conversion of biogenic synthesis gas with Clostridium carboxidivorans and Clostridium autoethanogenum

Anton Rückel, doctoral thesis Technical University of Munich, 2023

Biogenic syngas contains trace impurities such as NH3, H2S, and NOX. Applying Clostridium carboxidivorans in fully-controlled batch processes with continuous gassing showed that only NOx has to be reduced in the syngas, while Clostridium autoethanogenum additionally needs a reduction of the NH3-, and H2S-levels. When traces of O2 are reduced to at least 293 ppm, a pre-purified syngas from gasification of wood can be converted with both microorganisms without any negative effect compared to pure gases.


  • Oppelt A, Rückel A, Rupp M, Weuster-Botz D (2024): Mixotrophic syngas conversion enables the production of meso-2,3-butanediol with Clostridium autoethanogenum. Fermentation 10: 102.
  • Rückel A, Oppelt A, Leuter P, Johne P, Fendt S, Weuster-Botz D (2022): Conversion of syngas from entrained flow gasification of biogenic residues with Clostridium carboxidivorans and Clostridium autoethanogenum. Fermentation 8: 465.
  • Oliveira L, Rückel A, Nordgauer L, Schlumprecht P, Hutter E, Weuster-Botz D (2022): Comparison of syngas-fermenting Clostridia in stirred-tank bioreactors and the effects of varying syngas impurities. Microorganisms 10: 681.
  • Rückel A, Hannemann J, Maierhofer C, Fuchs A, Weuster-Botz D (2021): Studies on syngas fermentation with Clostridium carboxidivorans in stirred-tank reactors with defined gas impurities. Front Microbiol 12: 655390.
  • Doll K, Rückel A, Kämpf P, Weuster-Botz D (2018): Two stirred-tank bioreactors in series enable continuous production of alcohols from carbon monoxide with Clostridium carboxidivorans. Bioproc Biosys Eng 41:1403-1416.