Abstract
Although ethanol is now made from the sugars in the starch fraction of corn and other crops and from the sugar in sugarcane, a much greater impact for ethanol in terms of fuel use could be realized if the sugars from more recalcitrant cellulosic biomass could be converted to ethanol. Cellulosic biomass is the structural portion of plants and includes agricultural (e.g., corn stover, which is all of the above-ground portion of the corn plant, excluding the grain) and forestry (e.g., sawdust) residues, major fractions of municipal solid waste (e.g., waste paper and yard waste), and herbaceous (e.g., switchgrass) and woody (e.g., poplar) crops grown as energy resources. Although distinctive in outward appearance, these materials all comprise about 40–50% cellulose and 20–30% hemicellulose, with lesser amounts of lignin and other compounds such as sugars, oils, and minerals. Cellulose is a polymer of glucose sugar molecules that are physically linked together in a crystalline structure to provide structural support for plants. Hemicellulose is also made up of sugars covalently joined together in long chains, but it generally includes fve different sugars: arabinose, galactose, glucose, mannose, and xylose. In addition, hemicellulose is an amorphous, branched material. Lignin is a phenylpropene compound that can be viewed as a low-sulfur, immature coal.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
C.E. Wyman, S.R. Decker, M.E. Himmel, J.W. Brady, C.E. Skopec, L. Viikari, in Polysaccharides: Structural Diversity and Functional Versatility, S. Dumitriu, Ed. (Dekker, New York, ed. 2, 2004), p. 995.
C.E. Wyman, in Encyclopedia of Energy, C. Cleveland, Ed. (Elsevier, St. Louis, MO, 2004), p. 541.
C.E. Wyman, B.E. Dale, R.T. Elander, M. Holtzapple, M.R. Ladisch, Y.Y. Lee, Bioresour. Technol. 96 (18), 2026 (2005).
N. Mosier, C.E. Wyman, B. Dale, R. Elander, Y.Y. Lee, M. Holtzapple, M. Ladisch, Bioresour. Technol. 96 (6), 673 (2005).
C.E. Wyman, Applied Energy Technology Series, 424 (Taylor and Francis, Washington, DC, 1996).
U.S. Department of Energy, Energy Information Administration, Annual Energy Review 2005 (DOE Report DOE/EIA-0384, 2005).
R. Perlack, L. Wright, A. Turhollow, R. Graham, B. Stokes, D. Erbach, Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply (Oak Ridge National Laboratory, Oak Ridge, TN, 2005).
A.E. Farrell, R.J. Plevin, B.T. Turner, A.D. Jones, M. O’Hare, D.M. Kammen, Science 311, 506 (2006).
C.E. Wyman, Appl. Biochem. Biotechnol. 45–6, 897 (1994).
H.S. Kheshgi, R.C. Prince, Energy 30, 1865 (2005).
L.R. Lynd, C.E. Wyman, T.U. Gerngross, Biotechnol. Prog. 15 (5), 777 (1999).
U.S. Department of Energy, Office of Science, Breaking the Biological Barriers to Cellulosic Ethanol, a Joint Research Agenda, a Research Roadmap Resulting from Biomass-to-Biofuels Workshop, Rockville, December 2005 (DOE/SC 0095, June 2006).
C.E. Wyman, Annu. Rev. Energy Environ. 24, 189 (1999).
L.R. Lynd, R.T. Elander, C.E. Wyman, Appl. Biochem. Biotechnol. 57–58, 741 (1996).
C.E. Wyman, Trends Biotechnol. 25 (4), 153 (2007).
Chem. Eng. Prog. 100 (12), 15 (2004).
Chem. Eng. News 83 (17), 10 (April 25, 2005).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Wyman, C.E. Cellulosic Ethanol: A Unique Sustainable Liquid Transportation Fuel. MRS Bulletin 33, 381–383 (2008). https://doi.org/10.1557/mrs2008.77
Published:
Issue Date:
DOI: https://doi.org/10.1557/mrs2008.77