Aqueous Processing of Cellulosic Biomass for Biological Production of Sustainable Transportation Fuels

Abstract

Cellulosic biomass including agricultural and forestry residues, substantial fractions of municipal solid waste, and grasses and woody plants grown for energy provide the only low cost and abundant resource that could be used for sustainable production of liquid transportation fuels on a large scale. The challenge is to develop low cost processing technologies to convert this inexpensive resource into viable transportation fuels. Biological conversion systems can apply the power of modern biotechnology to dramatically reduce the costs of converting cellulosic biomass to fuels, and ethanol represents a particularly desirable product in the near term because of its excellent fuel properties, widespread use, and compatibility with biological conversion systems. Ethanol use can also build from commercial experience gained with ethanol made from starch crops in the United States and cane sugar in Brazil. The most expensive steps in biological processing are associated with breaking down the cellulose and hemicellulose fractions of biomass to release sugars, with pretreatment particularly critical to achieving low costs and high yields Our research focuses on improving the understanding of aqueous pretreatment and its interactions with enzymatic hydrolysis with the goal of reducing costs. This presentation will summarize comparative data on pretreatment technologies, developing and applying a high throughput miniaturized approach to pretreatment and hydrolysis, and continuous fermentations to reduce enzyme use. Once successfully introduced into the marketplace, fuels from cellulosic biomass can have powerful and unique strategic, environmental, and economic benefits.