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Cell growth behaviors of Clostridium acetobutylicum in a pervaporation membrane bioreactor for butanol fermentation

Acetone–butanol–ethanol fermentation using Clostridium acetobutylicum was studied in the continuous and closed‐circulating fermentation (CCCF) system. The experiment lasting for 192 H was carried out by integrating fermentation with in situ pervaporation. In the entire process, the cell growth profile took place in the following two phases: the logarithmic phase during early 28 H and the linear phase from 130 to 150 H. This was a unique characteristic compared with the curve of traditional fermentation, and the fitting equations of two growth phases were obtained by Origin software according to the kinetic model of cell growth. Besides, the kinetic parameters that include the butanol yield, maximum specific growth rate, average specific formation rate, and volumetric productivity of butanol were measured as 0.19 g g−1, 0.345 H−1, 0.134 H−1 and 0.23 g L−1 H−1, respectively. The C. acetobutylicum in the CCCF system showed good adaptability and fermentation performance, and the prolonged fermentation period and high production were also the main advantages of CCCF technology.