CHEMICAL COMMUNICATIONS
·
2017
·Vol. 53
·期 74
·10295-10298
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IF 6.319
Huihuang Fang,Junmou Du,Chenchen Tian,Jianwei Zheng,Xinping Duan,Linmin Ye,Youzhu Yuan
Evenly dispersed tungsten carbides with controlled phase compositions that exhibit an impressive capacity to carry out the regioselective hydrogenolysis of inert aryl ether C–O bonds instead of aliphatic C–O bonds to produce aromatic compounds are reported.
研究领域:
催化
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有机化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
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2024
·
IF 3.9
Zhijiao Huang,Yong Liu,Lungang Chen,Xinghua Zhang,Jianguo Liu,Chenguang Wang,Qi Zhang,Longlong Ma
2,5-dimethylfuran (DMF), a promising biomass-derived fuel, is synthesized via the hydrodeoxygenation of 5-hydroxymethylfurfural (HMF). This study focuses on the inherent activity of a 5Pt5Fe/C catalyst for HMF hydrodeoxygenation to DMF. The catalyst exhibited exceptional performance, achieving a remarkable DMF yield of 99.6 %. It displayed specific selectivity for C = O bond hydrogenation and C O bond cleavage in diverse substrates, producing high yield of 2-methylfuran from furfural and furfury alcohol, and high yield of toluene from benzaldehyde, benzyl alcohol. In-depth characterizations unveiled valuable insights into the 5Pt5Fe/C catalyst's properties, emphasizing a harmonious balance between metal and acid sites due to the interactive synergy between Pt and Fe species, enhancing hydrodeoxygenation activity. Additionally, the catalyst demonstrated satisfactory stability, maintaining a commendable DMF yield over five reaction cycles despite observed changes.
研究领域:
化学工程
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催化
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2024
·
IF 5.8
Yang-Yang Xu,Xing Fan,Feng-Yun Ma,Hai-Xu Zou,Xian-Yong Wei
Directly converting lignite into arenes as commodity chemicals and drop-in fuels is a highly desirable target for researchers. However, this is severely limited by the presence of stable inter unit C-O linkages in lignite. Herein, a highly active catalyst, Co-MoS 2 , has been designed and prepared to be used for the selective catalytic cleavage of inter unit C-O bridged bonds (BBs) in the conversion of Naomaohu (NMH), a lignite, to yield arenes. Both catalytic hydrogenation conversion (CHC) and thermal dissolution (a non-catalytic process, named NCHC) of NMH were conducted using n-hexane as the solvent. The soluble fractions from the first stage of NCHC (SF NCHC-1 ) and CHC (SF CHC-1 ), as well as the second stage of NCHC (SF NCHC-2 ) and CHC (SF CHC-2 ) were obtained using the same solvent. After the first-stage catalytic treatment, the relative contents of arenes and alkanes in SF CHC-1 increased by 16.7 % and 9.3 %, respectively, compared to those in SF NCHC-1 , and the relative content of oxygen-containing compounds (OCCs), such as alcohols, phenols , esters, ketones , acids, and furans, decreased by 13.2 %. For the second-stage conversion, the relative contents of arenes and alkanes in SF CHC-2 were 53.5 % and 15.5 % higher than those in SF NCHC-2 , and the relative contents of OCCs was only 6.6 % in SF CHC-2 . The catalytic mechanisms of cleavage of C-O BBs and deoxygenation were proposed based on the CHC of model compounds and density functional theory (DFT) calculation. The adsorption of OCCs and the activation of released hydrogen radical (H·) by Co-MoS 2 , followed by H· addition to the carbon atom connected to oxygen in C-O BBs and oxygen-containing functional groups, are crucial for the cleavage of C-O BBs and formation of deoxygenated compounds, particularly arenes.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
·
IF 3.8
Chuhan Zhang,Yanchang Chu,Linying Fu,Qiuyue Wang,Rui Ma,Donghai Xu,Le Yang
Lignin, a renewable resource rich in aromatic ring structures in nature, is an ideal natural source to produce aromatic compounds and cycloparaffin. Herein, we prepare MOF-derived Ni–MoxC/C and Co–MoxC/C as catalysts for the depolymerization of lignin and dimeric model compounds. Diphenyl ether (DPE) with 4-O-5 bond, benzyl phenyl ether (BPE) with α-O-4, and phenethyl phenyl ether (PPE) with β-O-4 are chosen as dimeric model compounds. Overall, Ni–MoxC/C and Co–MoxC/C show distinguished different activity toward product distribution. Ni–MoxC/C facilitates both C–O bond cleavage and hydrogenation of the benzene ring, and the main products are ethyl cyclohexane and cyclohexanol for all three model compounds. In contrast, Co–MoxC/C only facilitates C–O bond cleavage and obtains phenol and ethylbenzene as products. Similarly, for the depolymerization of lignin, cycloparaffins are obtained on Ni–MoxC/C, while phenol, guaiacol, 2,6-dimethoxyphenol, and their respective derivatives are obtained on Co–MoxC/C.
研究领域:
化学工程
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可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2019
·
IF 4.745
Na Li,Jinku Bai,Xiaolin Zheng,Honghua Rao
An iron-catalyzed methylene forming strategy is disclosed through sequential C–H and C–O bond functionalization of methanol with cosolvent water. This protocol provides an easy and novel access to methylene-tethered imidazo[1,2-a]pyridine and 2-aminopyridine analogues in a sustainable manner and represents a complementary approach to traditional methylene forming strategies.
研究领域:
有机化学
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催化化学
✓ 已验证
DOI
PubMed
高影响因子
Catalysts
·
2022
·Vol. 12
·期 12
·1625
·
IF 4.501
Bo Chen,Zhi-Ze Cao,Zhi-Jun Diao,Liang-Qiu Huang,Si-Jia Zhao,Hong Yuan,Jia-Meng He
Hydrogenolysis via targeted depolymerization of C–O linkages is a techno-economic beneficial process for converting lignin into highly valuable chemicals and clean fuels. In this work, a macroporous silicalite-1 (S-1) array-supported Ru-Ni metallic phosphide composite (Ru-Ni12P5/S-15) was prepared as a catalyst and hydrogenolysis activity under relative mild conditions was investigated using a series of compounds containing ether linkages as lignin-related model compounds. The Lewis acid sites originating from the unreduced Ru species and the macroporous geometry of S-1 significantly influenced hydrogenolysis activity and product selectivity. Analysis of the mechanism demonstrated that both the aryl ether and aliphatic ether linkages were directly hydrogenated over Ru-Ni12P5/S-15. 2D-HSQC-NMR spectroscopy demonstrated that the ether linkages of lignin were efficiently cleaved by Ru-Ni12P5/S-15. Furthermore, the obtained liquid hydrogenolysis products are high value-added chemicals used for pharmaceutical production and can be facilely tuned via the reaction conditions.
研究领域:
催化化学
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可再生资源转化
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Zhi-Yuan Zheng,Zhi-Feng Jiao,Ji-Xiao Zhao,Xin-Chao Liu,Cai-Dong Song,Jia-Hang Li,Xiang-Yun Guo
In the hydrogenation of polyfunctional compounds, achieving high selectivity for specific functional groups remains challenging. Herein we report that SiC quantum dots (QDs) can selectively adsorb C = O in cinnamaldehyde, significantly increasing the activity and selectivity of Pt/SiC for hydrogenating cinnamaldehyde to cinnamyl alcohol. A 10 wt% QDs-modified Pt/SiC catalyst showed a turnover frequency 3.5 times higher than Pt/SiC under mild conditions. Further studies reveal that the defect-rich surface of SiC QDs facilitates the adsorption of C = O bond in cinnamaldehyde and enhances the spillover of active hydrogen from Pt to SiC QDs. During the catalysis process, Pt is responsible for the generation of reactive hydrogen species while the QDs undertake the activation of C = O bond, and the hydrogen species react with cinnamaldehyde via spillover. This work demonstrates the promise of SiC QDs in heterogeneous catalysis and provides a reference for designing novel hydrogenation catalysts.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL RESEARCH
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2021
·
IF 0.782
Chun-Jing Li
We report a direct cross-coupling reaction between (het)aryl pivalates/tosylates and di(het)arylzinc species in 2-methyltetrahydrofuran/N-methyl pyrrolidone (1:1), which occurs via C–O bond cleavage under microwave irradiation. The reaction takes place smoothly in short reaction times without the addition of any catalyst or ligand. The reaction is suitable for a broad scope of substrates and exhibits good functional group compatibility, utilizes a simple work-up procedure, and gives the desired products in high purity.
研究领域:
有机化学
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合成化学
✓ 已验证
DOI
高影响因子
FUEL
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2024
·
IF 6.7
Yuqaio Ma,Xinping Ouyang,Lisha Zhao,Lifeng Li,Xueqing Qiu
The lignin-first strategy is a crucial approach for highly efficient depolymerization of lignin to produce aromatic monomers as the condensation of lignin occurred during the separating process which increased the difficulty in depolymerization. In this work, a cobalt atom clusters supported on nitrogen-doped carbon catalysts (Co/NC-15) was prepared by adjusting the dosage of melamine to control the morphology, structure, and pyridinic nitrogen content of the catalysts. DFT calculations based on lignin model showed that the doping of nitrogen increased the adsorption energy of the lignin on the supports and decreased the dissociation energy of C-O bonds. Under lignin first strategy, Co/NC-15 exhibited good ability to break C-O bonds at 220 °C of mild condition, in which 84.32 wt% of lignin in lignocellulosic biomass was converted into 40.62 wt% of aromatic monomers, while 84.02 wt% of cellulose was preserved. The atom clusters Co/NC-15 exhibited good catalytic activity to lignin depolymerization due to efficient cleavage of C-O bonds, and hence showed the promising prospect in potential industrial application.
研究领域:
生物化学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2016
·
IF 9.307
Nengchao Luo,Min Wang,Hongji Li,Jian Zhang,Huifang Liu,Feng Wang
One of the challenges of depolymerizing lignin to valuable aromatics lies in the selective cleavage of the abundant C–O bonds of β-O-4 linkages. Herein we report a photocatalytic oxidation–hydrogenolysis tandem method for cleaving C–O bonds of β-O-4 alcohols. The Pd/ZnIn2S4 catalyst is used in the aerobic oxidation of α-C–OH of β-O-4 alcohols to α-C═O with 455 nm light, and then a TiO2–NaOAc system is employed for cleaving C–O bonds neighboring the α-C═O bonds through a hydrogenolysis reaction by switching to 365 nm light. Interestingly, the oxidation–hydrogenolysis tandem reaction can be conducted in one pot to offer ketones and phenols (up to 90% selectivity) via a dual light wavelength switching (DLWS) strategy. EPR and metal loading experiments elucidate that Ti3+ in TiO2 is formed in situ and is responsible for the photocatalytic hydrogenolysis through electron transfer from Ti3+ to the β-O-4 ketones.
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2016
·Vol. 9
·期 22
·3220-3229
·
IF 7.116
Haiwei Guo,Bo Zhang,Changzhi Li,Chang Peng,Tao Dai,Haibo Xie,Aiqin Wang,Tao Zhang
Graphical Breaking up : Tungsten carbide shows remarkable activity in selective C−O bond cleavage of typical β-O-4 model compounds and deconstruction of lignin feedstocks. High yields of C−O cleavage products from model compounds (up to 96.8 %) and from lignin feedstock (up to 70.7 %) are obtained without destroying the aromatic rings. A remarkably effective method for the chemoselective cleavage of the C−O bonds of typical β-O-4 model compounds and the deconstruction of lignin feedstock was developed by using tungsten carbide as the catalyst. High yields of C−O cleavage products (up to 96.8 %) from model compounds and liquid oils (up to 70.7 %) from lignin feedstock were obtained under low hydrogen pressure (0.69 MPa) in methanol. The conversion efficiency was determined to a large extent by solvent effects and was also affected by both the electronic and steric effects of the lignin model compounds. In situ W 2 C/activated carbon (AC)-catalyzed hydrogen transfer from methanol to the substrate was proposed to be responsible for the high performance in methanol solvent. The conversion of 2-(2-methoxyphenoxy)-1-phenylethanol showed that the catalyst could be reused five times without a significant loss in activity for C−O bond cleavage, whereas the selectivity to value-added styrene increased markedly owing to partial oxidation of the W 2 C phase according to X-ray diffraction, Raman spectroscopy, and transmission electron microscopy characterization. 2 D-HSQC-NMR spectroscopy analysis showed that W 2 C/AC exhibited high activity not only for β-O-4 cleavage but also for the deconstruction of more resistant α-O-4 and β-β linkages, so that a high yield of liquid oil was obtained from lignin. Corn stalk lignin was more liable to be depolymerized than birch lignin owing to its loosened structure (scanning electron microscopy results), larger surface area (BET results), and lower molecular weight (gel-permeation chromatography results), whereas its liquid oil composition was more complicated than that of birch wood lignin in that the former lignin contained more p -hydroxyphenyl units and the former contained noncanonical units.
研究领域:
化学工程
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材料科学
·
生物质能
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2018
·
IF 0
Jiang Li,Hui Sun,Jia-xing Liu,Jun-jie Zhang,Zhen-xing Li,Yao Fu
Lignin has recently attracted much attention as a promising resource to produce fuels and aromatic chemicals. The selective cleavage of C O bond while preserving the aromatic nature has become one of the major challenges in the catalytic valorization of lignin to aromatic chemicals. In this work, we report that the selective reductive cleavage of C O bond in lignin model compounds can be successfully achieved through heterogeneous iron catalysis. The hydrogenolysis of α-O-4 model linkage shows that the iron catalyst prepared by the simultaneous pyrolysis of iron acetate and 1,10-phenanthroline on activated carbon at 800 °C is the most active iron catalyst, affording phenol and toluene with yields of 95% and 90%, respectively. This aromatics selectivity is found to be much higher than that obtained over noble metal catalysts. The presence of N⋯Fe species as the active center of heterogeneous iron catalyst was confirmed by various technologies especially XPS and H 2 -TPR. For the β-O-4 model linkage, the vicinal OH group was essential for the iron-catalyzed hydrogenolysis of ether linkage. The oxidation of the α-carbon in the β-O-4 model compounds can significantly decrease the bond dissociation energy of ether linkage, giving depolymerization products in moderate to excellent yields.
研究领域:
催化化学
·
可再生资源化学
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）