Second-Generation Biofuel Production from Corn-Ethanol Industry Residues

  • Prachand Shrestha
  • Anthony L PomettoIII
  • Samir Kumar Khanal
  • J. (Hans) van Leeuwen
Part of the Green Energy and Technology book series (GREEN)


Net ethanol production per unit mass of corn kernel can be significantly improved by utilizing fibrous co-products to produce cellulosic ethanol. Corn fiber is a good cellulosic feedstock to produce second-generation biofuel. A biorefinery concept is introduced to convert fibrous residue, corn fiber, into fermentable sugars at a lower temperature with minimal use of chemicals. Laboratory-scale consolidated fermentation system comprised of on-site fungal enzyme production system and simultaneous saccharification and fermentation (SSF) yielded 7.1, 8.6 and 4.1 g ethanol per 100 g corn fiber when saccharified with the white-, brown-, and soft-rot fungi, respectively. The highest corn-to-ethanol yield (8.6 g ethanol/100 g corn fiber) was equivalent to 42% of the theoretical ethanol yield from starch and cellulose in corn fiber. This is equivalent to 120 l of ethanol per metric ton of corn fiber. With process optimization, conversion of over 70% of corn fiber carbohydrate content into ethanol can generate as much as 13x109 l of ethanol per year, which is equivalent to 25% of the current annual ethanol production (52x109 l) in the US, additional $8.65 billion annual revenue and reduction in corn acreage by 3 mha. It is also possible to convert the carbohydrates to a fuel oil using a secondary oleaginous fungal process. The residual fiber enriched with fungal protein can still be utilized as animal feed without unbalancing the feed market/supply.


Ethanol Production Corn Stover Ethanol Yield Fermentable Sugar Corn Fiber 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag London Limited  2012

Authors and Affiliations

  • Prachand Shrestha
    • 1
  • Anthony L PomettoIII
    • 2
  • Samir Kumar Khanal
    • 3
  • J. (Hans) van Leeuwen
    • 4
  1. 1.Energy Biosciences Institute (EBI)University of CaliforniaBerkeleyUSA
  2. 2.Food Sciences and Human NutritionClemson UniversityClemsonUSA
  3. 3.Molecular Bioscience and BioengineeringUniversity of Hawaii at ManoaHonoluluUSA
  4. 4.Civil, Construction and Environmental EngineeringIowa State UniversityAmesUSA

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