College of Engineering

Bioethanol Production

The use of renewable resources to meet domestic energy needs would reduce dependence on foreign energy sources, alleviate air pollution problems, and increase employment opportunities (www.nrel.gov). Cellulosic biomass is an abundant and inexpensive renewable resource that can be used to provide a carbohydrate source for ethanol fermentations. A major drawback, however, is that the microorganisms used in the ethanol fermentations are subject to product inhibition and other toxicity problems. For this project, teams of student researchers are assembled as a cohort of 2 biology and 2 chemical engineering majors, and each cohort works with a team of 4 professors (2 from biology and 2 from chemical engineering). The student cohorts select a particular toxicological problem to investigate over a two-year period. The arc of each cohort’s project is broken down into modules with specific objectives that include an extensive biological and engineering literature search and review, isolation of novel toxin-resistant derivatives of known ethanologenic microbes, quantification of the toxicological properties of the new strains, and pilot fermentation studies to demonstrate the effectiveness of the new strains. All students participate in presentations of their results at national microbiology and chemical engineering conferences. The module approach and the cohort composition emphasize multidisciplinary learning. The experiments conducted by the students address applied microbiology, toxicology, fermentation technology, engineering design, economics, and professional communication. All the students in the cohort participate in all phases of the experimental design and execution, including determining the effects of altering process variables (e.g., feedstock composition), isolation and characterization of the biological catalyst with the desired properties, assessing the impact of these activities on the process conditions of the downstream operations and the overall economic feasibility of the system, and dissemination of the results at professional venues.