TY - JOUR
T1 - Revealing the Molecular Structural Transformation of Hardwood and Softwood in Dilute Acid Flowthrough Pretreatment
AU - Zhang, Libing
AU - Pu, Yunqiao
AU - Cort, John R.
AU - Ragauskas, Arthur J.
AU - Yang, Bin
N1 - Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/12/5
Y1 - 2016/12/5
N2 - To understand better the intrinsic recalcitrance of lignocellulosic biomass, the main hurdle to its efficient deconstruction, the effects of dilute acid flowthrough pretreatment on the dissolution chemistry of hemicellulose, cellulose, and lignin for both hardwood (e.g., poplar wood) and softwood (e.g., lodgepole pine wood) were investigated at temperatures of 200 to 270 °C and a flow rate of 25 mL/min with 0.05% (w/w) H2SO4. Results suggested that the softwood cellulose was more readily degraded into monomeric sugars than that of hardwood under same pretreatment conditions. However, while the hardwood lignin was completely removed into hydrolysate, ∼30% of the softwood lignin remained as solid residues under identical conditions, which was plausibly caused by vigorous C5-active recondensation reactions (C-C5). Effects of molecular structural features (i.e., lignin molecular weight, cellulose crystallinity, and condensed lignin structures) on the recalcitrance of hardwood and softwood to dilute acid pretreatment were identified for the first time in this study, providing important insights to establish the effective biomass pretreatment.
AB - To understand better the intrinsic recalcitrance of lignocellulosic biomass, the main hurdle to its efficient deconstruction, the effects of dilute acid flowthrough pretreatment on the dissolution chemistry of hemicellulose, cellulose, and lignin for both hardwood (e.g., poplar wood) and softwood (e.g., lodgepole pine wood) were investigated at temperatures of 200 to 270 °C and a flow rate of 25 mL/min with 0.05% (w/w) H2SO4. Results suggested that the softwood cellulose was more readily degraded into monomeric sugars than that of hardwood under same pretreatment conditions. However, while the hardwood lignin was completely removed into hydrolysate, ∼30% of the softwood lignin remained as solid residues under identical conditions, which was plausibly caused by vigorous C5-active recondensation reactions (C-C5). Effects of molecular structural features (i.e., lignin molecular weight, cellulose crystallinity, and condensed lignin structures) on the recalcitrance of hardwood and softwood to dilute acid pretreatment were identified for the first time in this study, providing important insights to establish the effective biomass pretreatment.
KW - Flowthrough pretreatment
KW - Hardwood
KW - Lignin chemistry
KW - Lignin recondensation
KW - Softwood
UR - http://www.scopus.com/inward/record.url?scp=85002369649&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.6b01491
DO - 10.1021/acssuschemeng.6b01491
M3 - Article
AN - SCOPUS:85002369649
SN - 2168-0485
VL - 4
SP - 6618
EP - 6628
JO - ACS Sustainable Chemistry and Engineering
JF - ACS Sustainable Chemistry and Engineering
IS - 12
ER -