INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2021
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IF 3.764
Xiaoxue Li,Xiaopo Niu,Shuaikang Zhu,Shuang Xu,Zheyuan Wang,Xiangwen Zhang,Qingfa Wang
Fabricating zeolite-supported catalysts with excellent catalytic performance for hydroconversion of bio-oils into high-quality fuels is still a great challenge. Herein, hierarchical ZSM-5 zeolites were successfully synthesized with 3-[(trimethoxysilyl) propyl] octadecyldimethylammonium chloride as a mesoporous template. The hierarchical ZSM-5 supported Pt catalysts (Pt/HZ-x) were used to enhance the hydrodeoxygenation of dibenzofuran into bicyclohexane, and the influence of acidity distribution on the reaction pathways was investigated by tailoring the Si/Al molar ratios (50, 75, and 100). For all catalysts, cycloalkanes were produced via the partial hydrogenation of the aromatic rings to generate tetrahydrodibenzofuran, followed by the cleavage of C—O bond. The optimal bicyclohexane selectivity (86.8%) was obtained on Pt/HZ-75 catalyst due to the good synergistic effect between metal dispersion and acid distribution. This catalyst also showed excellent stability because of its strong metal–support interactions. Even after reused five times, the catalytic activity was almost unchanged compared with the fresh one. Furthermore, the possible reaction pathways for conversion of dibenzofuran into bicyclohexane over Pt/HZ-x catalysts were developed.
研究领域:
催化
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化学工程
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材料科学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2022
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IF 4.326
Li-Yun Zhang,Jing-Pei Cao,Xue-Yu Ren,Xiao-Bo Feng,Jing-Xian Wang,Zi-Meng He,Tian-Long Liu,Zhen Yang,Xiao-Yan Zhao,Hong-Cun Bai
CeO2 receives extensive researches as an active component due to its providential catalytic center and favorable reducibility. Herein, a series of Ce-modified hierarchical ZSM-5 zeolites (FZ5) were prepared by HF (0.5 mol/L) etching followed by impregnation with different Ce loadings. The role of incorporating extra-framework Ce elements was assessed by catalytic upgrading of the cellulose pyrolysis volatiles to produce light aromatics (LAs). Introducing CeO2 could effectively regulate the acid properties of catalysts with an increase in Lewis acid sites and a decrease in Brönsted acid sites, which could significantly improve the catalytic performance. As a result, the selectivity toward LAs were significantly enhanced and the coke content dramatically decreased. The highest selectivity to LAs and the lowest coke content obtained over 1.0Ce-FZ5 zeolite (loading 1.0 wt % Ce) were 84.0% and 2.42 wt %, respectively. Additionally, the 1.0Ce-FZ5 catalyst exhibited excellent stability, maintaining nearly 90% carbon yield of LAs after the seventh regeneration test. CeO2 modification opened a simple and feasible way for promoting the LAs selectivity and catalyst stability during the reforming of biomass volatiles.
研究领域:
催化化学
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生物质能源
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材料化学
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环境科学
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能源化工
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
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2023
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IF 5.3
Haifeng Tian,Zhiyu Chen,Xing Yang,Peng Gao,Chunxue Jiao,Fei Zha,Yue Chang,Hongshan Chen
A method for the direct synthesis of hierarchical zeolites was developed by converting precursors of zeolites and mesoporous copolymers into homogeneous gels using conventional block copolymers as scaffolds. In this method, hydrothermal synthesis is accomplished on a steam-assisted basis, and the dry gel leaves the system free of the liquid water phase, which successfully avoids phase separation between the soft stencil and the solid silica phase. The catalytic performance of hierarchical zeolites was evaluated on a fixed-bed reactor for the methanol-to-aromatics reaction. The hierarchical structure greatly enhances the catalytic activity of the probe reaction due to the increased outer surface, decreased coke formation, and diffusion resistance in the microporous network. The selectivity of BTX reached 65.8%, and there was no significant deactivation after a reaction of 107 h. The transition state and energy barrier for methanol to aromatics were obtained by the minimum energy search of the LST/QST transition state.
研究领域:
化学工程
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催化
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2017
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IF 6.035
Li Peng,Xiaohan Xu,Xun Yao,Hua Liu,Xuehong Gu
A series of novel hierarchical ZSM-5 zeolite membranes with tunable mesopore sizes have been prepared successfully by using amphiphilic organosilane 3-[(trimethoxysilyl) propyl]octyldimethyl-ammonium chloride (TPOAC) as the mesogenous template and part of the Si source. The effects of several synthesis parameters, such as the TPOAC/SiO 2 ratio, synthesis temperature and crystallization time, on the microstructures and rejection performance of the hierarchical ZSM-5 zeolite membranes were systematically investigated. Multiple techniques, such as XRD , SEM, N 2 adsorption techniques, TEM, IR, 13 C MAS NMR and 29 Si MAS NMR were employed for the characterizations. The filtration of dextran in water shows that the membranes have molecular weight cutoff (MWCO) ranging from 9500 to 943,000, corresponding to the molecular size in the range of 4.5–37 nm. The sharp increase in the rejection of dextran with the increase of molecular weight indicated narrow pore size distribution of the membrane. These results show that the hierarchical mesoporous ZSM-5 zeolite membranes have a great potential for ultrafiltration with high performance.
研究领域:
材料科学
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化学工程
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膜技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）