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Optimization of dilute-acid pretreatment of corn stover using a high-solids percolation reactor


We have previously demonstrated that pretreatment of corn stover with dilute sulfuric acid can achieve high digestibility and efficient recovery of hemicellulose sugars with high yield and concentration. Further improvement of this process was sought in this work. A modification was made in the operation of the percolation reactor that the reactor is preheated under atmospheric pressure to remove moisture that causes autohydrolysis. This eliminated sugar decomposition during the preheating stage and led to a considerable improvement in overall sugar yield. In addition, liquid throughput was minimized to the extent that only one reactor void volume of liquid was collected. This was done to attain a high xylose concentration in the hydrolyzate. The optimum reaction and operating conditions were identified wherein near quantitative enzymatic digestibilities are obtained with enzyme loading of 15 FPU/g glucan. With a reduced enzyme loading of 5 FPU/g glucan, the enzymatic digestibility was decreased, but still reached a level of 92%. Decomposition of carbohydrates was extremely low as indicated by the measured glucan and xylan mass closures (recovered sugar plus unreacted) which were 98% and 94%, respectively. The data obtained in this work indicate that the digestibility is related to the extent of xylan removal.

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  1. 1.

    Nguyen, Q. A. and Saddler, J. N. (1991), Biores. Technol. 35, 275–282.

    Article  CAS  Google Scholar 

  2. 2.

    Shah, R. B., Clausen, E. C., and Gaddy, J. L. (1984), Chem. Eng. Prog. 80, 76–80.

    CAS  Google Scholar 

  3. 3.

    Zhu, Y. Lee, Y. Y., and Elander, R. T. (2004), Appl. Biochem. Biotechnol. 117, 103–114.

    PubMed  Article  CAS  Google Scholar 

  4. 4.

    Laboratory Analytical Procedures (1996), NREL, Golden, CO.

  5. 5.

    Lee, Y. Y., Iyer, P., and Torget, R. W. (1999), Advances in Biochem. Eng./Biotech. 65, 93–115.

    CAS  Google Scholar 

  6. 6.

    Knappert, D., Grethlein, H., and Converse, A. (1980), Biotech. Bioeng. 22, 1449–1463.

    Article  CAS  Google Scholar 

  7. 7.

    Um, B-H, Karim, M. N., and Henk, L. L. (2003), Appl. Biochem. Biotechnol. 105–108, 115–125.

    PubMed  Article  Google Scholar 

  8. 8.

    Schell, D. J., Walter, P. J., and Johnson, D. K. (1992), Appl. Biochem. Biotechnol. 34–35, 659–665.

    Google Scholar 

  9. 9.

    Schell, D. J., Farmer, J., Newman, M., and McMillan, J. D. (2003), Appl. Biochem. Biotechnol. 105–108, 69–85.

    PubMed  Article  Google Scholar 

  10. 10.

    Schell, D. J., Farmer, J., and Zuccarello, M. (2004), Dilute sulfuric acid pretreatment of corn stover in a continuous pilot-scale reactor: impact of high solids loading on sugar yield and enzymatic cellulose digestibility, presented at 26th Symposium on Biotechnology for Fuels and Chemicals, Chattanooga, Tennessee, May 9–12, 2004.

  11. 11.

    Kim, T. H., Kim, J. S., Sunwoo, C., and Lee, Y. Y. (2003), Bioresource Technol. 90, 39–47.

    Article  CAS  Google Scholar 

  12. 12.

    Chang, V. S., and Holtzapple, M. T. (2000), Appl. Biochem. Biotechnol. 84–86, 5–37.

    PubMed  Article  Google Scholar 

  13. 13.

    Holtzapple, M. T., Lundeen, J. E., Sturgis, R., Lewis, J. E., and Dale, B. E. (1992), Appl. Biochem. Biotechnol. 34–35, 5–21.

    Google Scholar 

  14. 14.

    Gould, J. M. (1984) Biotechnol. Bioengineer. 26, 46–52.

    Article  CAS  Google Scholar 

  15. 15.

    Wu, Z., and Lee, Y. Y. (1997), Appl. Biochem. Biotechnol. 63–65, 21–34.

    Article  Google Scholar 

  16. 16.

    Grethlein, H. E. (1985), Bio. Technology 3, 155–164.

    CAS  Google Scholar 

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Correspondence to Y. Y. Lee.

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Zhu, Y., Lee, Y.Y. & Elander, R.T. Optimization of dilute-acid pretreatment of corn stover using a high-solids percolation reactor. Appl Biochem Biotechnol 124, 1045–1054 (2005).

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Index Entries

  • Corn stover
  • dilute-acid hydrolysis
  • percolation process
  • pretreatment
  • high sugar recovery
  • low enzyme loading