TY - JOUR
T1 - A review of bio-oil upgrading by catalytic hydrotreatment
T2 - Advances, challenges, and prospects
AU - Zhang, Mingyuan
AU - Hu, Yulin
AU - Wang, Haoyu
AU - Li, Haoyang
AU - Han, Xue
AU - Zeng, Yimin
AU - Xu, Chunbao Charles
PY - 2021/3
Y1 - 2021/3
N2 - Fast pyrolysis and hydrothermal liquefaction (HTL) have been regarded as the most promising thermochemical conversion technologies for liquid bio-fuels production. However, the poor quality of generated crude bio-oils, such as high O and water contents, low thermal stability, and high corrosivity, limits their direct applications as the alternative transportation fuels. Thus, a number of upgrading techniques mainly including chemical and physical methods have been developed. Among them, hydrotreatment like hydrodeoxygenation (HDO) as a well-established technology at petroleum refinery plants has been widely adopted for upgrading of the crude oil obtained from pyrolysis or HTL. In this review, the effects of various upgrading reaction conditions (temperature, H2 pressure, solvents, residence time, and catalyst) of HDO treatment of real bio-oil and its mode compounds are thoroughly reviewed. In which, the underlying mechanisms for bio-oil HDO are elucidated with a wide range of its model compounds (lignin-derived oxygenates and carbohydrates-derived oxygenates) and the interaction between these model compounds. Moreover, a discussion regarding the HDO of real bio-oil from pyrolysis and HTL is provided, and the technical/operating problems for the catalytic HDO and the possible solutions are presented. Finally, the important knowledge gaps and future directions are addressed for further investigations. © 2021 Elsevier B.V.
AB - Fast pyrolysis and hydrothermal liquefaction (HTL) have been regarded as the most promising thermochemical conversion technologies for liquid bio-fuels production. However, the poor quality of generated crude bio-oils, such as high O and water contents, low thermal stability, and high corrosivity, limits their direct applications as the alternative transportation fuels. Thus, a number of upgrading techniques mainly including chemical and physical methods have been developed. Among them, hydrotreatment like hydrodeoxygenation (HDO) as a well-established technology at petroleum refinery plants has been widely adopted for upgrading of the crude oil obtained from pyrolysis or HTL. In this review, the effects of various upgrading reaction conditions (temperature, H2 pressure, solvents, residence time, and catalyst) of HDO treatment of real bio-oil and its mode compounds are thoroughly reviewed. In which, the underlying mechanisms for bio-oil HDO are elucidated with a wide range of its model compounds (lignin-derived oxygenates and carbohydrates-derived oxygenates) and the interaction between these model compounds. Moreover, a discussion regarding the HDO of real bio-oil from pyrolysis and HTL is provided, and the technical/operating problems for the catalytic HDO and the possible solutions are presented. Finally, the important knowledge gaps and future directions are addressed for further investigations. © 2021 Elsevier B.V.
KW - Biomass
KW - Crude bio-oil
KW - Fast pyrolysis
KW - Hydrodeoxygenation (HDO)
KW - Hydrothermal liquefaction
UR - http://www.scopus.com/inward/record.url?scp=85100734672&partnerID=8YFLogxK
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-85100734672&origin=recordpage
U2 - 10.1016/j.mcat.2021.111438
DO - 10.1016/j.mcat.2021.111438
M3 - RGC 21 - Publication in refereed journal
SN - 2468-8231
VL - 504
JO - Molecular Catalysis
JF - Molecular Catalysis
M1 - 111438
ER -
