Butanol Production by Clostridium Acetobutylicum: Assessment of Acidogenesis Kinetics

The growth kinetics of Clostridium acetobutylicum ATCC824 under controlled acidogenesis conditions has been investigated. Tests were carried out in a CSTR equipped with a pH-controller. Synthetic medium was used, with lactose acting as carbon source. Acids typically produced during the fermentation process were eventually supplemented to investigate their critical effects on the kinetic growth. The conversion process has been characterized under steady state conditions in terms of concentration of cells, acids, pH, total organic compounds and dilution rate. The kinetics has been modelled in agreement with a multiple product inhibition model and parameters of the model have been assessed. The maximum specific growth rate estimated under steady state conditions (0.95 h-1) resulted about three time the value estimated batch cultures.