TY - JOUR
T1 - Selective Aerobic Upgrading of Lignin-Derived Compound Using a Recyclable Dual-Functional TPO-Loaded Cu-BTC Catalyst
AU - Lin, Jia Yin
AU - Ghanbari, Farshid
AU - Ok, Yong Sik
AU - Lisak, Grzegorz
AU - Lin, Kun Yi Andrew
AU - Chang, Fang Chih
N1 - Funding Information:
This work is supported by the Ministry of Science and Technology (MOST) (108-2636-E-005-001), Taiwan, and financially supported by the “Innovation and Development Center of Sustainable Agriculture” from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE), Taiwan.
Funding Information:
This work is supported by the Ministry of Science and Technology (MOST) (108-2636-E-005-001), Taiwan, and financially supported by the ?Innovation and Development Center of Sustainable Agriculture? from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE), Taiwan.
Publisher Copyright:
© 2020, Springer Nature B.V.
PY - 2021/2
Y1 - 2021/2
N2 - Abstract: As oxidative conversion of lignin-derived compound, vanillic alcohol (VA), to vanillin aldehyde (VL) represents as a useful process for lignocellulosic biomass valorization. While catalytic aerobic oxidation by Cu and 2,2,6,6-tetramethylpiperidine 1-oxyl (TPO) with O2 as an oxidant is proposed as a promising oxidative process for VA conversion, this conventional Cu/TPO employs homogeneous Cu ions and TPO, making recovery of homogeneous Cu ion and TPO from reaction media extremely challenging. Herein, Cu species and TPO are integrated into a single heterogeneous catalyst through a co-precipitation method to embed TPO into copper benzene-1,3,5-tricarboxylate (CuBTC) metal organic frameworks (MOFs), forming a bifunctional heterogeneous catalyst. The resulting TPO-embedded CuBTC (TEC) retained the typical octahedral morphology and crystalline structure of CuBTC, while encapsulating TPO within CuBTC. The TEC exhibited higher conversion efficiencies of VA than the simple combination of pristine CuBTC and TPO. A higher TPO embedment in TEC, higher temperature and longer reaction time substantially enhanced VA oxidation, and thus TEC with 12.5 wt% of TPO embedment at 120 °C and 2-h reaction time could achieve CVA > 98%, SVL = 100% and YVL > 98%. The TEC is also proven to be reusable for continuous VA oxidation. These features indicate that TEC is a promising heterogeneous catalyst which incorporates the dual catalytic functions of Cu sites and TPO moieties into a catalytic system to continuously, effectively and selectively oxidize VA to VL. Graphic Abstract: [Figure not available: see fulltext.].
AB - Abstract: As oxidative conversion of lignin-derived compound, vanillic alcohol (VA), to vanillin aldehyde (VL) represents as a useful process for lignocellulosic biomass valorization. While catalytic aerobic oxidation by Cu and 2,2,6,6-tetramethylpiperidine 1-oxyl (TPO) with O2 as an oxidant is proposed as a promising oxidative process for VA conversion, this conventional Cu/TPO employs homogeneous Cu ions and TPO, making recovery of homogeneous Cu ion and TPO from reaction media extremely challenging. Herein, Cu species and TPO are integrated into a single heterogeneous catalyst through a co-precipitation method to embed TPO into copper benzene-1,3,5-tricarboxylate (CuBTC) metal organic frameworks (MOFs), forming a bifunctional heterogeneous catalyst. The resulting TPO-embedded CuBTC (TEC) retained the typical octahedral morphology and crystalline structure of CuBTC, while encapsulating TPO within CuBTC. The TEC exhibited higher conversion efficiencies of VA than the simple combination of pristine CuBTC and TPO. A higher TPO embedment in TEC, higher temperature and longer reaction time substantially enhanced VA oxidation, and thus TEC with 12.5 wt% of TPO embedment at 120 °C and 2-h reaction time could achieve CVA > 98%, SVL = 100% and YVL > 98%. The TEC is also proven to be reusable for continuous VA oxidation. These features indicate that TEC is a promising heterogeneous catalyst which incorporates the dual catalytic functions of Cu sites and TPO moieties into a catalytic system to continuously, effectively and selectively oxidize VA to VL. Graphic Abstract: [Figure not available: see fulltext.].
KW - CuBTC
KW - Lignin
KW - Oxidative reaction
KW - Tetramethylpiperidine 1-oxyl
KW - Vanillic alcohol
KW - Vanillin aldehyde
UR - http://www.scopus.com/inward/record.url?scp=85081753767&partnerID=8YFLogxK
U2 - 10.1007/s12649-020-01009-1
DO - 10.1007/s12649-020-01009-1
M3 - Article
AN - SCOPUS:85081753767
SN - 1877-2641
VL - 12
SP - 673
EP - 685
JO - Waste and Biomass Valorization
JF - Waste and Biomass Valorization
IS - 2
ER -
