A novel bacterial system with integrated micro-bubble distillation for the production of acetaldehyde
Acronym: Z-Fuels

- Graeme Hitchen - Perlemax Limited - United Kingdom
- Uldis Kalnenieks - University of Latvia - Latvia
- Per Bruheim - NTNU Norwegian University of Science and Technology - Norway
- Katja Bettenbrock - Max-Planck-Institute for Dynamics of Complex Technical Systems - Germany
- Oliver Sawodny - University of Stuttgart - Germany

Butanol is a desirable biofuel as its characteristics most closely match gasoline and allows using current gasoline fuel infrastruture and vehicles. Its production however is limited by the energy requirements needed for its synthesis from ethanol and the poor yields.  A known intermediary in butanol production is acetaldehyde, the production of which involves high cost.  Microorganisms exist which can produce acetaldehyde directly. The bacterium wymomonas mobilis is the most prominent example, which bears a great potential for bioprocess improvement by metabolic engineering. However, the process yields and productivity are restricted by the metabolic inhibition caused by the produced acetaldehyde. The concept of the present project is to design, construct and operate a bacterial process, based on genetically engineered Z. mobilis with an integrated microbubble distillation system to convert complex sugary feedstocks and crude glycerol to acetaldehyde.  Effective removal of acetaldehyde during the metabolic process will alleviate the inhibition and give higher yields.  From the higher production quantities of acetaldehyde a more competitive and efficient route to butanol production can be obtained compared to current practise.