Ethanol fermentation kinetics in a continuous and closed-circulating fermentation system with a pervaporation membrane bioreactor

The kinetics of ethanol fermentation by Saccharomyces cerevisiae was studied in a continuous and closed-circulating fermentation (CCCF) system with a polydimethylsiloxane (PDMS) pervaporation membrane bioreactor. Three sequential 500-h cycles of CCCF experiments were carried out. A glucose volumetric consumption of 3.8 g L−1 h−1 and ethanol volumetric productivity of 1.39 g L−1 h−1 were obtained in the third cycle, with a specific glucose utilization rate of 0.32 h−1 and ethanol yield rate of 0.13 h−1. The prolonged fermentation time and good fermentation performance indicate that the CCCF would be a feasible and promising fermentation process technology.