Butanol production by bioconversion of cheese whey in a continuous packed bed reactor

Butanol production by Clostridium acetobutylicum DSM 792 fermentation was investigated. Unsupplemented cheese whey was adopted as renewable feedstock. The conversion was successfully carried out in a biofilm packed bed reactor (PBR) for more than 3. months.The PBR was a 4cm ID, 16cm high glass tube with a 8cm bed of 3mm Tygon rings, as carriers. It was operated at the dilution rate between 0.4h-1 and 0.94h-1.The cheese whey conversion process was characterized in terms of metabolites production (butanol included), lactose conversion and biofilm mass. Under optimized conditions, the performances were: butanol productivity 2.66. g/Lh, butanol concentration 4.93. g/L, butanol yield 0.26. g/g, butanol selectivity of the overall solvents production 82. wt%. �� 2013 Elsevier Ltd.