Trickle-Bed Bioreactors for Acetogenic H2/CO2 Conversion

Acetic acid is an essential industrial building block and can be produced by acetogenic bacteria from molecular hydrogen (H 2 ) carbon dioxide (CO ). When gasses are supplied as substrates, bioreactor design plays important role for their availability. Trickle-bed bioreactors (TBs) have enhanced gas-to-liquid mass transfer cells remain in the system forming a biofilm on carriers. So far, TBs been investigated extensively bio-methanation processes, whereas studies use acetic production rare. In this study, we evaluated reproducibility of two parallel H :CO (= 70:30) mixed culture with gas flow rate 3.8 mL min ?1 medium 10 . Additionally, effect glucose addition during starting phase resulting products microbial composition was setting up third TB2. Partial exchanges to decrease internal concentration (AAC) combined recycling withdrawn had positive impact rates maxima around 1 g L d even at high AACs 19–25 Initial resulted accumulation unwanted butyric concentrations 2.60 ± 0.64 The maximum AAC 40.84 obtained without initial addition. main families identified were Peptococcaceae, Ruminococcaceae, Planococcaceae, Enterobacteriaceae, Clostridiaceae, Lachnospiraceae, Dysgonomonadaceae Tannerellaceae. We conclude that TB viable solution conversion /CO acetate using anaerobic enrichment culture.