TY - JOUR
T1 - Effects of lignin structure on hydrodeoxygenation reactivity of pine wood lignin to valuable chemicals
AU - Wang, Hongliang
AU - Ben, Haoxi
AU - Ruan, Hao
AU - Zhang, Libing
AU - Pu, Yunqiao
AU - Feng, Maoqi
AU - Ragauskas, Arthur J.
AU - Yang, Bin
N1 - Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/2/6
Y1 - 2017/2/6
N2 - Hydrodeoxygenation (HDO) of two dilute acid flowthrough pretreated softwood lignin samples, including residual lignin in pretreated solid residues (ReL) and recovered insoluble lignin in pretreated liquid (RISL), with apparent different physical and chemical structures, was comprehensively studied. A combination of catalysts (HY zeolite and Ru/Al2O3) was employed to investigate the effects of lignin structures, especially condensed structures, on the HDO upgrading process. Results indicated that the condensed structure and short side chains in lignin hindered its HDO conversion under different reaction conditions, including catalyst loading and composition, hydrogen pressure, and reaction time. In addition to lignin structure, HY zeolite was found crucial for lignin depolymerization, while Ru/Al2O3 and relatively high hydrogen pressure (4 MPa) were necessary for upgrading unstable oxy-compounds to cyclohexanes at high selectivity (>95 wt %). Since the lignin structure essentially affects its reactivity during HDO conversion, the yield and selectivity of HDO products can be predicted by detailed characterization of the lignin structure. The insights gained from this study in the fundamental reaction mechanisms based on the lignin structure will facilitate upgrading of lignin to high-value products for applications in the production of both fuels and chemicals.
AB - Hydrodeoxygenation (HDO) of two dilute acid flowthrough pretreated softwood lignin samples, including residual lignin in pretreated solid residues (ReL) and recovered insoluble lignin in pretreated liquid (RISL), with apparent different physical and chemical structures, was comprehensively studied. A combination of catalysts (HY zeolite and Ru/Al2O3) was employed to investigate the effects of lignin structures, especially condensed structures, on the HDO upgrading process. Results indicated that the condensed structure and short side chains in lignin hindered its HDO conversion under different reaction conditions, including catalyst loading and composition, hydrogen pressure, and reaction time. In addition to lignin structure, HY zeolite was found crucial for lignin depolymerization, while Ru/Al2O3 and relatively high hydrogen pressure (4 MPa) were necessary for upgrading unstable oxy-compounds to cyclohexanes at high selectivity (>95 wt %). Since the lignin structure essentially affects its reactivity during HDO conversion, the yield and selectivity of HDO products can be predicted by detailed characterization of the lignin structure. The insights gained from this study in the fundamental reaction mechanisms based on the lignin structure will facilitate upgrading of lignin to high-value products for applications in the production of both fuels and chemicals.
KW - Biofuel
KW - Condensed lignin
KW - Hydrodeoxygenation
KW - Lignin reactivity
KW - Softwood lignin
UR - http://www.scopus.com/inward/record.url?scp=85011661236&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.6b02563
DO - 10.1021/acssuschemeng.6b02563
M3 - Article
AN - SCOPUS:85011661236
SN - 2168-0485
VL - 5
SP - 1824
EP - 1830
JO - ACS Sustainable Chemistry and Engineering
JF - ACS Sustainable Chemistry and Engineering
IS - 2
ER -