Industrial & Engineering Chemistry Research, Vol.58, No.4, 1502-1512, 2019
Kinetic Modeling of the Isobutanol Production from Glucose Using Shimwellia blattae (p424IbPSO) Strain: Effect of Initial Substrate Concentration
Isobutanol production from glucose using Shimwellia blattae (p424IbPSO) has been studied. Experiments were carried out under conditions previously determined: medium M92X, in a stirred tank bioreactor closed after 2 h. Growth was carried out under aerobic conditions, and the production occurred under anaerobic conditions. Five runs were conducted employing different initial substrate concentrations, between 30 and 70 g.L-1. A kinetic model is proposed describing growth rate, metabolite production rates (isobutanol, ethanol, and organic acids), and glucose consumption rate. The kinetic model fits very well all the experimental data, and the kinetic parameter values calculated are consistent with the initial glucose concentration employed in each run. Both substrate (glucose) and product (isobutanol) inhibition are evident. Biomass growth rate depends on oxygen availability but is not influenced by glucose concentration in the interval studied. Maximum yield and productivity on isobutanol are reached in the experiment carried out employing 45 g.L-1 as the initial glucose concentration.