Coupled iron-microbial catalysis for CO2 hydrogenation with multispecies microbial communities

Elise Blanchet (1) , Zoï Vahlas (1) , Luc Etcheverry (1) , Yan Rafrafi (1) , Benjamin Erable (1) , Marie-Line Délia (1) , Alain Bergel (1)

1 LGC - Laboratoire de Génie Chimique

The hydrogenation of carbon dioxide offers a large range of possible reactions for converting hydrogen to chemical compounds that can be easily stored, transported and used as fuels or platform molecules. In this study, CO 2 hydrogenation was biocatalysed by multispecies microbial communities to produce formate, butyrate and acetate. A hybrid metal/microbial catalysis was pointed out in the presence of iron. Addition of FeCl 3 10 mM increased the production of acetate by 265 % and butyrate by 73 %, to 5.26 and 14.19 g/L, respectively. A stable acetate production rate of 830 mg/L/d was thus sustained for more than 20 days. The presence of iron promoted the selection of Firmicutes and the best performances were linked to the growth of a restricted number of dominant species of two genera: Clostridium and Megasphaera. Various possible catalysis mechanisms are discussed and guidelines are proposed for further development and scale-up of the process.

Mots clés: biocatalysis; gas-liquid; green chemistry; sustainable chemistry; environmental inoculum; electron transfer

Domaines: Sciences de l'ingénieur [physics]

Elise Blanchet, Zoï Vahlas, Luc Etcheverry, Yan Rafrafi, Benjamin Erable, et al.. Coupled iron-microbial catalysis for CO2 hydrogenation with multispecies microbial communities. Chemical Engineering Journal, 2018, 346, pp.307-316. ⟨10.1016/j.cej.2018.03.191⟩. ⟨hal-03750998⟩