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Fundamentals of production from renewable feedstocks and use as a transportation fuel


Ethanol can be directly blended with gasoline, reacted with isobutylene to form the oxygenated fuel additive ethyl tert-butyl ether (ETBE), or burned directly as a neat fuel. Blends of either ethanol or ETBE with gasoline force engines set for gasoline to run lean and can substantially reduce carbon monoxide emissions. ETBE also lowers the overall vapor pressure, thereby cutting back on smog-forming emissions. Neat ethanol further reduces smog formation since it has a low volatility, the photochemical reactivity of ethanol and its combustion products is low, and low levels of smog producing compounds are formed by ethanol combustion. Neat ethanol also offers good engine performance owing to its high heat of vaporization, high octane, and low flame temperature.

Fermentation stoichiometry reveals that many feedstocks are expensive for fuels production even considering coproduct credits and ignoring conversion costs, whereas lignocellulosic feedstocks cost much less than their value. Furthermore, the quantities of lignocellulosics are projected to be ample even for neat ethanol production. Release of carbon dioxide during fermentation concentrates almost all the heat of combustion from the solid carbohydrate portion in liquid ethanol. Since the carbon dioxide released during production and use of ethanol is recycled during growth of biomass, ethanol utilization doesn’t contribute to the accumulation of carbon dioxide in the atmosphere and possible global warming.

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  1. Reisch, M. (1988),C&E News (October), pp. 11, 12.

  2. Lichty, L. C. and Ziurys, E. J. (1936),Ind. and Eng. Chem. 28, 1094.

    Article  CAS  Google Scholar 

  3. Ricardo, H. R. (1941),The High Speed Internal Combustion Engine, Interscience, New York, 434 pp.

    Google Scholar 

  4. Summary Report of Performance of Commercial Gasolines Blended with Ethanol, (1956), Southwest Research Inst., San Antonio, TX.

  5. Fuel Ethanol Cost-Effectiveness Study, Final Report (1987), National Advisory Panel on Cost-Effectiveness of Fuel Ethanol Production. Report for US Secretary of Agriculture.

  6. Egloff, G. and Morrel, J. C. (1936),Ind. and Eng. Chem. 28, 1080.

    Article  CAS  Google Scholar 

  7. Martin Grayson, ed. (1984),Encyclopedia of Chemical Technology: Alcohol Fuels to Toxicology, (supplement), Wiley, New York.

    Google Scholar 

  8. Jackson, M. W., Wiese, W. M., and Wentworth, J. T., (1964),SAE preprint 486A, March. Included in SAE Tech. Progress Book TP-6, 1964. 9. Sperling, D. (1988),New Transportation Fuels: A Strategic Approach to Technological Change, University of California Press, Los Angeles.

  9. Lynd, L. R. (1989),Adv. Biochem. Eng./Biotechnol. 38, 1.

    CAS  Google Scholar 

  10. Young, J., Griffin, E., and Russel, J. (1986),Biomass 10, 9.

    Article  CAS  Google Scholar 

  11. Jeffries, T. W. (1983),Adv. Biochem. Eng./Biotechnol. 27, 1.

    CAS  Google Scholar 

  12. Ng, T. K., Busche, R. M., McDonald, C. C, and Hardy, R. W. F. (1983),Science 219, 733.

    Article  CAS  Google Scholar 

  13. Ferchak, J. D. and Pey, E. K. (1981),Solar Energy 26, 9.

    Article  CAS  Google Scholar 

  14. OTA (Office of Technology Assessment) (1980),Energy from Biological Processes, Technical and Environmental Analyses, vol. II, Congress of the United States, Washington, DC.

    Google Scholar 

  15. Humphrey, A. E., Moreira, A., Armiger, W., and Zabriske, D. (1977),Biotech. Bioeng. Symp. 7, 45.

    CAS  Google Scholar 

  16. Goldstein, I. S. (1981),Organic Chemicals from Biomass, Goldstein, I.S., ed., CRC Press, Boca Raton, FL, p. 1.

    Google Scholar 

  17. Vergara, W. and Pimentel, D. (1978),Energy from Biomass and Wastes Symposium, May 14–18, Washington, DC.

  18. Wright, J. D. (1988),Ethanol from Lignocellulose, internal report.

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Wyman, C.E., Hinman, N.D. Ethanol. Appl Biochem Biotechnol 24, 735–753 (1990).

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Index Entries

  • Fuels
  • emissions
  • ethanol
  • feedstocks
  • green-house effect