Ethanol Production by Bacterial Fermentation

摘要

The goal of this study is to develop and optimize the process technology for the production of ethanol using the bacteria Zymomonas mobilis. Specifically, the process and operating conditions will be studied to maximize the yield of ethanol. The experimental design is described using both batch and continuous cultures with glucose as the substrate. Separation methods, therefore, will be developed to remove the alcohol from the fermentation media to prevent the inhibitory effects of ethanol on Z. mobilis. Vacuum fermentation and solvent extraction can be used to separate the alcohol from the media. Kinetic data will be obtained from both the batch and continuous fermentors. The kinetic data can be correlated using mathematical models. Mathematical models for Z. mobilis will be developed for the effect of pH, temperature and nutrient composition on the specific growth rate. A model will also be developed to account for the possible product inhibition by ethanol. Dynamic tests will also be conducted on the continuous system to determine how fast the fermentation will respond to environmental changes. The simultaneous hydrolysis of cellulose to glucose and fermentation of glucose to ethanol is one of the most exciting possibilities. A literature survey will be made to determine the compatibility of conducting the hydrolysis reaction along with the bacterial fermentation. The final objective will be to make an economic assessment of the process of producing ethanol using Z. mobilis. (ERA citation 10:022491)