Submitted to: Liquid Fuels from Renewable Resources Conference Proceedings
Publication Type: Review Article
Publication Acceptance Date: September 17, 1996
Publication Date: N/A
Technical Abstract: Over 1.3 billion gallons of fuel ethanol are produced annually in the United States, with approximately 95% derived from corn starch. Now with increased attention to clean air and oxygenates for fuels, an opportunity exists for an expanded alcohol fuel industry. Corn fiber represents a renewable resource that is available in sufficient quantities from the corn wet milling industry to serve as a low cost feedstock for production of fuel alcohol. Corn fiber consists primarily of lignocellulosic biomass and starch and is currently marketed in corn gluten feed. Several promising pretreatment and enzymatic processes have potential for conversion of corn fiber cellulose, hemicellulose, and the remaining starch to fermentable sugars. In all cases, these hydrolysates are rich in pentoses (D-xylose and L-arabinose) and glucose. Superior ethanologenic microorganisms that can ferment pentose and hexose sugars have been developed using recombinant techniques. Specifically, we have evaluated batch and continuous dilute acid, ammonia fiber explosion, and enzyme treatments for the hydrolysis of corn fiber. These hydrolysates were then examined for ethanol productivity and yield in bioreactors using genetically modified bacteria and yeasts. Application of these novel bioprocessing technologies has the potential to lower the cost of ethanol production and improve the competitiveness of ethanol as a fuel or fuel additive.