초록
<P><B>Abstract</B></P> <P>A kinetic model describing acetone-butanol-ethanol (ABE) production applicable to both single substrate fermentations of glucose and xylose as well as co-fermentation of the substrates has been developed. The model accounts for carbon catabolite repression as well as the inhibition of kinetic rates at high substrate concentrations (∼90 g l<SUP>−1</SUP>). Model parameters were obtained through kinetic fitting to previously report experimental data. The model was used to study the design and operation of a continuous ABE fermentation process (with and without recycle of biomass). For continuous operation, it was shown that multiple steady-states exist at low dilution rates. For operation with recycle of biomass, the influence of recycle rate on both biomass concentration and ABE productivity were studied. The results indicate that for a range of recycle and dilution rates, ABE productivity can increase to 16 g l<SUP>−1</SUP> h<SUP>−1</SUP> (10 times higher than that without biomass recycling), consistent with experimental results.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel kinetic model describing acetone-butanol-ethanol production is developed. </LI> <LI> The model accounts for carbon catabolite repression. </LI> <LI> The model is validated using both batch and continuous fermentation data. </LI> <LI> Butanol inhibited the production of ACoA, acetone, AACoA, pyruvate and biomass. </LI> <LI> A productivity up to 16 g l<SUP>−1</SUP> h<SUP>−1</SUP> can be achieved by cell-recycling. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>