Grant: Strategic Projects Supplemental Competition

The depletion of fossil fuels makes the search of alternative or renewable energy sources more imperative. While several renewable energy forms, such as ethanol, hydrogen, and biodiesel, have demonstrated their applicative potential, butanol starts to gain more attention in this aspect. Compared to methanol or ethanol as a common gasoline supplement, butanol contains more carbon content, has a higher energy content, and is safer to handle and less corrosive. Compared to gasoline, butanol has approximately the same energy content and fuel efficiency but is more environmentally friendly. With a high cetane number of CN25, butanol can be blended with petrodiesel or biodiesel to reduce the gel temperature point and the viscosity. Currently, butanol is produced primarily via petrochemical processing. In response to the recently soaring oil price, the biological route can become more competitive if cheaper feedstock is identified and biotransformation yield andproductivity are enhanced. Recognizing the importance of butanol as a promising alternative energy, a joint venture between British Petroleum and DuPont was recently initiated for the large-scale production of biobutanol in UK. Biobutanol is often referred as one of the major metabolites of ABE (acetone, butanol, and ethanol) fermentation using an anaerobe, such as Clostridium acetobutylicum and Clostridium butyricum, etc. These strict anaerobic bacteria have specific metabolic pathways for degradation of a wide variety of carbon sources to drive solvent production. The possibility of simultaneous hydrogen generation can also improve energy yield. With recent advances in biotechnology and bioprocessing, butanol has gained a renewed interest. In the proposed research, we will develop innovative bioprocess strategies for butanol production via ABEfermentation, including strain construction, bioreactor system, and butanol recovery, and conduct economic analysis to evaluate the feasibility of the developed bioprocess.