FUEL
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2024
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IF 6.7
Zhuang Li,Zi-Chun Fan,Xiang Bai,Xian-Yong Wei,Yierxiati. Dilixiati,Qian-Qian Kong,Ji Zhao,Yong-Hui Feng,Jun-Long Wang,Xing Fan,Xiao-Yan He,Hai-Xu Zou,Zhi-Min Zong
MY zeolites with mesopores were prepared by hydrothermal method using functionalized SiO 2 (F-SiO 2 ) as a silica source, and hydrophobic bifunctional Ru/MY- O catalysts were obtained by deposition precipitation method and silylation treatment. This work aims at obtaining polycyclic alkane (PCA) based high-density hydrocarbon fuels (HDHFs). We focused on the catalytic hydroconversion (CHC) of 2-phenoxy-1-phenylethanol (PP-ol) and oxydibenzene (ODB), two typical lignin-related model compounds (LRMCs), over Ru/MY- O . The effects of different reaction conditions and catalysts on the product distribution in PP-ol and ODB were investigated. The partial hydrogenation of ODB was found to be a necessary step before achieving C-O ether bond cleavage and C-C bond coupling. The balance of metal/acidic sites is critical for maximizing PCA yields. Changes in the metal/acid ratio had a greater effect on PCA yield in PP-ol than in ODB. Poor stability of cycloalkyl cations and partial hydrogenation of ODB hinder the generation of C-C coupling products. The incorporation of mesopores and hydrophobic treatment were found to weaken the negative effects of C-C bond coupling products and water on the catalyst. The conversion of Ru 3 /MY- O was improved by nearly 10% compared to Ru 3 /Y in the fifth cycle reaction. This work provided a theoretical basis for the generation of HDHFs from lignin.
研究领域:
化学工程
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催化
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可再生能源
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
·
2020
·Vol. 68
·期 4
·582-591
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IF 1.554
Changzhou Chen,Peng Liu,Haihong Xia,Minghao Zhou,Jianchun Jiang
There is an urgent need to develop a selective hydrogenolysis of C aryl -O bonds in lignin to produce valued-added chemicals and fuels. Recently, hydrogen has been used in the hydrogenation reaction, which hides inevitable danger and is not economical. Therefore, isopropanol, as a hydrogen-donor solvent, is employed for aryl ether hydrogenolysis in lignin models over nickel supported on a carbon nanotube (CNT). Except for aromatic ether (4-O-5), the Ni/CNT catalyst is also found to be suitable for alkyl-aryl ether (α-O-4 and β-O-4) cleavage in control experiments. The physicochemical characterizations were carried out by means of H 2 -temperature-programmed reduction, X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy analyses. The catalyst can be magnetically recovered and efficiently reused for five consecutive recycling tests in the transfer hydrogenation of aromatic ethers. A mechanism study indicated that the hydrogenolysis cleavage of the ether bond is the first step in the reaction process, and hydrogenation of aromatic rings is only a successive step in which phenol and benzene are intermediate states and are then further hydrogenated. Furthermore, it has been demonstrated that aryl groups play an important role in the hydrogenation of phenol in the competitive catalytic hydrogenation reaction of phenol.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
BMC Chemistry
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2019
·Vol. 13
·期 1
·1-15
·
IF 0
Guo J.,Ma Yu L.,Yu Jia Y.,Gao Yu J.,Ma Ning X.,Wu Xiao Y.
Herein, 2-(2-methoxyphenoxy)-1-phenylethanol (β- O -4), 2-methoxyphenyl anisole (α- O -4) and 4-phenoxyphenol (4- O -5) were selected as typical lignin model compounds. Given the effectiveness of traditional acid–base catalysts for lignin depolymerisation, a novel Ni/CaO–H-ZSM-5(60) catalyst was prepared to investigate the difficulty level of C–O bond of three model compounds cleavage in ethanol. It was observed that Ni/CaO–H-ZSM-5(60) had prominent performance on the C–O bond cleavage at very mild conditions (140 °C, 1 MPa H 2 ). Among them, the C–O bond of α- O -4 and β- O -4 could be completely cleaved within 60 min. Although the C–O bond of 4- O -5 had high bond energy, 41.2% of conversion was occurred in 60 min. The introduction of CaO could regulate the acidity of H-ZSM-5 to enhance the ability to break C–O bonds. Moreover, the possible pathways of C–O ether bonds in three lignin model compounds cleavage were proposed in order to selectively obtain target products from the raw lignin degradation.
研究领域:
化学工程
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催化科学
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DOI
FUEL PROCESSING TECHNOLOGY
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2021
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IF 7.033
Xiangchen Kong,Chao Liu,Weicong Xu,Yue Han,Yuyang Fan,Ming Lei,Ming Li,Rui Xiao
Stubborn lignin (SL) is the thermochemically stable fragment generated from biomass utilization (e.g., pyrolysis , hydrolysis, fermentation, pulping), which is comparatively difficult to be further depolymerized into value-added bio-products. The cleavage of the stubborn linkages within the structure of SL, such as C C, α -O-4, and 4-O-5 linkages, is the key for its valorization. Herein, we investigated the depolymerization of SL through catalytic hydroprocessing in supercritical methanol with Cu/CuMgAlO x catalyst. The yield of monomers reached 37.76C% with 240 min at 300 °C. Cyclohexanols were identified as the major monomeric products, indicating the occurrence of hydrodeoxygenation and hydrogenation. GPC , quantitative 13 C NMR, HSQC NMR, and HMBC NMR analyses evidenced the depolymerization of SL and upgrading of its derivatives. Furthermore, the mechanistic studies were carried out to provide insights to the stubborn linkage cleavages. The degrees of difficulty to break up the three involved linkages obeyed the sequence of β -5 > 4-O-5 > α -O-4. The apparent activating energies ( E a ), chemisorption energies ( E c ), and bond dissociation energies (BDE) were determined computationally to support the experimental results from the perspectives of kinetics, chemisorption, and thermodynamics, respectively. This research provides a reliable way for the utilization of SL.
研究领域:
化学工程
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催化
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生物化学
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可再生能源
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产品关联
DOI
高影响因子