Butanol production by clostridium acetobutylicum in a continuous packed bed reactor fed with cheese whey

This research work reports on the feasibility of bio-butanol production by fermentation of cheese whey in a continuous packed bed reactor (PBR). The anaerobic solventogenic bacterium Clostridium acetobutylicum DSM 792 was adopted for the fermentation processes and commercial cheese whey powder was adopted as substrate. The fermentation plant consisted of a PBR, liquid pumps, a thermostatic unit, and a pH control unit. The PBR was a 4 cm ID, 16 cm high glass tube with a 8 cm bed of 3 mm Tygon rings, as carriers. The pH ranged between 4.5 and 5.5, the dilution rate (D) between 0.4 h-1 and 0.64 h-1. The PBR feedstock was a solution of deproteinized cheese whey powder. Results show that the best performance (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%w) was at D=0.54 h-1. Copyright �� 2013, AIDIC Servizi S.r.l.