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Title: Fractionating Recalcitrant Lignocellulose at Modest Reaction Conditions

Abstract

Effectively releasing the locked polysaccharides from recalcitrant lignocellulose to fermentable sugars is among the greatest technical and economic barriers to the realization of lignocellulose biorefineries because leading lignocellulose pre-treatment technologies suffer from low sugar yields, and/or severe reaction conditions, and/or high cellulase use, narrow substrate applicability, and high capital investment, etc. A new lignocellulose pre-treatment featuring modest reaction conditions (50 C and atmospheric pressure) was demonstrated to fractionate lignocellulose to amorphous cellulose, hemicellulose, lignin, and acetic acid by using a non-volatile cellulose solvent (concentrated phosphoric acid), a highly volatile organic solvent (acetone), and water. The highest sugar yields after enzymatic hydrolysis were attributed to no sugar degradation during the fractionation and the highest enzymatic cellulose digestibility ({approx}97% in 24 h) during the hydrolysis step at the enzyme loading of 15 filter paper units of cellulase and 60 IU of beta-glucosidase per gram of glucan. Isolation of high-value lignocellulose components (lignin, acetic acid, and hemicellulose) would greatly increase potential revenues of a lignocellulose biorefinery.

Authors:
 [1];  [2];  [3];  [4];  [4];  [4];  [3];  [2];  [4]
  1. Virginia Polytechnic Institute and State University (Virginia Tech)
  2. National Energy Renewable Laboratory
  3. ORNL
  4. Dartmouth College
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
930941
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biotechnology and Bioengineering; Journal Volume: 97; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; LIGNIN; CELLULOSE; ENZYMATIC HYDROLYSIS; SOLVENTS; POLYSACCHARIDES; FRACTIONATION; HEMICELLULOSE; SACCHARIDES; CHEMICAL REACTION YIELD

Citation Formats

Zhang, Y.-H. Percival, Ding, Shi-You, Mielenz, Jonathan R, Cui, Jing-Biao, Elander, Richard T., Laser, Mark, Himmel, Michael, McMillan, James R., and Lynd, L. Fractionating Recalcitrant Lignocellulose at Modest Reaction Conditions. United States: N. p., 2007. Web. doi:10.1002/bit.21386.
Zhang, Y.-H. Percival, Ding, Shi-You, Mielenz, Jonathan R, Cui, Jing-Biao, Elander, Richard T., Laser, Mark, Himmel, Michael, McMillan, James R., & Lynd, L. Fractionating Recalcitrant Lignocellulose at Modest Reaction Conditions. United States. doi:10.1002/bit.21386.
Zhang, Y.-H. Percival, Ding, Shi-You, Mielenz, Jonathan R, Cui, Jing-Biao, Elander, Richard T., Laser, Mark, Himmel, Michael, McMillan, James R., and Lynd, L. Mon . "Fractionating Recalcitrant Lignocellulose at Modest Reaction Conditions". United States. doi:10.1002/bit.21386.
@article{osti_930941,
title = {Fractionating Recalcitrant Lignocellulose at Modest Reaction Conditions},
author = {Zhang, Y.-H. Percival and Ding, Shi-You and Mielenz, Jonathan R and Cui, Jing-Biao and Elander, Richard T. and Laser, Mark and Himmel, Michael and McMillan, James R. and Lynd, L.},
abstractNote = {Effectively releasing the locked polysaccharides from recalcitrant lignocellulose to fermentable sugars is among the greatest technical and economic barriers to the realization of lignocellulose biorefineries because leading lignocellulose pre-treatment technologies suffer from low sugar yields, and/or severe reaction conditions, and/or high cellulase use, narrow substrate applicability, and high capital investment, etc. A new lignocellulose pre-treatment featuring modest reaction conditions (50 C and atmospheric pressure) was demonstrated to fractionate lignocellulose to amorphous cellulose, hemicellulose, lignin, and acetic acid by using a non-volatile cellulose solvent (concentrated phosphoric acid), a highly volatile organic solvent (acetone), and water. The highest sugar yields after enzymatic hydrolysis were attributed to no sugar degradation during the fractionation and the highest enzymatic cellulose digestibility ({approx}97% in 24 h) during the hydrolysis step at the enzyme loading of 15 filter paper units of cellulase and 60 IU of beta-glucosidase per gram of glucan. Isolation of high-value lignocellulose components (lignin, acetic acid, and hemicellulose) would greatly increase potential revenues of a lignocellulose biorefinery.},
doi = {10.1002/bit.21386},
journal = {Biotechnology and Bioengineering},
number = 2,
volume = 97,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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