APPLIED CATALYSIS B-ENVIRONMENTAL
·
2016
·
IF 8.328
Jing Guo,Shanhui Zhu,Youliang Cen,Zhangfeng Qin,Jianguo Wang,Weibin Fan
A series of ordered mesoporous Nb x W (8 − x) oxides with tunable Nb/W ratio were successfully synthesized by evaporation-induced self-assembly method. The mesoporous structure, morphologies, surface chemical state, and acidic properties of these catalysts were fully characterized by low-temperature sorption of N 2 , small-angle and wide-angle XRD, TEM, Raman, XPS, and Py-IR. It was shown that the Nb x W (8 − x) oxides created large amounts of Lewis as well as Brønsted acid sites, which promoted the isomerization of glucose to fructose followed its dehydration to 5-hydroxymethylfurfural (HMF). Mannose was also formed via the epimerization of glucose. Of them, the mesoporous Nb 4 W 4 exhibited the best catalytic activity with a comparatively low E a about 90.2 kJ/mol and good stability in aqueous medium. The kinetic behavior revealed that Lewis acid sites facilitated to glucose-to-fructose isomerization while Brønsted acid sites promoted the dehydration of fructose to form HMF.
研究领域:
催化化学
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生物质转化
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绿色化学
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多相催化
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材料化学
·
碳水化合物化学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2017
·Vol. 36
·期 3
·187-193
·
IF 1.852
Qing-Ning Zhao,Qing-Wen Song,Ping Liu,Qian-Xia Zhang,Jun-Hua Gao,Kan Zhang
The production of fine chemicals using CO 2 as C 1 building block through inexpensive heterogeneous catalysts with high efficiency under low pressure is challenging. Herein we propose for the first time the utilization of a multifunctional heterogeneous zinc-modified HZSM-5 (ZnHZSM-5) catalyst for upgrading CO 2 by incorporation into cyclic carbonates from CO 2 and epoxides. Owing to the nice surface properties such as abundant Lewis acid, Brønsted acid and Lewis base sites, large surface area, and plenty of micropores, CO 2 could be concentrated and well activated in ZnHZSM-5 verified by CO 2 -TPD, TG-MS, etc . Meanwhile, the epoxides were also activated through metal center and hydrogen bond. Therefore, the reaction can easily assemble at the catalyst interface and show exceptional performance, affording the aimed products with high yield of up to 99% in the presence of commercial tetra- n -propylammonium bromide (90% in kilogram scale with 0.004 mol% ZnHZSM-5 and 0.015 mol% n Pr 4 NBr).
研究领域:
催化化学
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环境化学
·
绿色化学
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材料化学
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有机合成
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能源化学
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工业化学
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DOI
高影响因子
AICHE JOURNAL
·
2023
·Vol. 69
·期 6
·e18054
·
IF 3.7
Feng Xiong,Chen Ji,Shengzhi Gan,Peng Liang,Yi Huang,Jin Shang,Baoyu Liu,Jinxiang Dong
Mesoscopically structured ZSM-5 nanosheets were prepared as highly active catalysts for the alkylation between toluene with methanol. The results showed that the Brønsted acid sites of ZSM-5 nanosheets were mainly distributed on the external surface in aluminum-rich zeolites owing to the charge-balance between positive quaternary ammonium cation (N + ) in C ph-10-6-6 , Na + ions and negative aluminosilicate species. In addition, it revealed that high alkalinity was easier to depolymerize the Si O Si species in Aluminum-rich synthesis gel, and the high alkalinity was required for silica-rich systems to dissolve silica species in order to finish the self-assemble process, leading to ZSM-5 nanosheets with high alkalinity presenting enhanced catalytic performance. Moreover, the optimized ZSM-5-50-2.5 was effective for the alkylation between toluene and methanol with toluene conversion of up to 50%, and it was stably operated for 48 h under the harsh conditions of WHSV = 32.5 h −1 with a desired stability.
研究领域:
催化
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化学工程
·
材料科学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Jun Xiao,Mengmeng Wang,Yaru Wang,Xunxun Li,Jiaqin He,Yunchong Liu,Qingfeng Xu,Hua Li,Najun Li,Dongyun Chen,Jianmei Lu
Catalytic oxidation is one of the most promising methods to remove toluene; manganese-cerium catalysts have high activity in the catalytic oxidation of toluene. Herein, nano-sized ZSM-5 was synthesized using a simple hydrothermal method, and catalysts with different Mn and Ce contents were prepared via alcohol-induced redox precipitation at room temperature. In addition, zeolite provides sufficient surface area for the dispersion of manganese cerium catalysts and plays a role in concentration and enrichment in the catalytic conversion of toluene. Based on the experimental characterization results, the 20Ce/M1Z1 catalyst exhibited the best catalytic activity, achieving 90% toluene conversion at 215 °C. Moreover, the catalyst still has excellent catalytic activity in humid environments. This work provides a new strategy to expose more active sites and enhance toluene adsorption, which provides a reference for the development of more efficient catalysts in the future.
研究领域:
环境科学
·
催化材料
✓ 已验证
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2014
·Vol. 25
·期 4
·755-762
·
IF 1.077
Wu Kai-Fei,Jiang Fen,Xiao Han,Bai Xian-Li,Mo Shao-Yin,Feng Yu
Three new metal–organic complexes [Fe(pyip)(H 2 O) 2 ] n ( 1 ), [Co(pyip)(H 2 O) 2 ] n ( 2 ) and [Ni(pyip)(H 2 O) 2 ] n ( 3 ) have been synthesized and characterized based on the carboxylic acid with N donor ligand (H 2 pyip=5-(Pyridin-3-yl)isophthalic acid). X-ray structure analysis reveals that complexes 1 – 3 showed identical 3-D supramolecular architecture that adopt different metal center. They all crystallize in hexagonal space group P 6(5) and exhibited exclusive coordination mode. One of the H 2 pyip adopt bidentate chelate coordination mode and the other coordination carboxylate oxygen atom adopts the single dentate bridging mode. Moreover, the two novel complexes were characterized by IR spectrum, elemental analysis, fluorescent properties, thermogravimetric analysis and powder X-ray diffraction.
研究领域:
无机化学
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材料科学
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配位化学
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晶体工程
·
高分子化学
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DOI
高影响因子
Biomass Conversion and Biorefinery
·
2022
·Vol. 13
·期 18
·17247-17254
·
IF 4.05
Wang Wei,Zhang Zhe,Wang Min
The electrochemical catalytic oxidation of 5-hydroxymethylfurfural (HMF) derived from biomass to produce 2,5-furandicarboxylic acid (FDCA) has attracted significant attention. Herein, the catalyst NiO-N/C composite was prepared and showed high activity for the electrochemical oxidation of HMF. The optimized NiO-N/C composite electrode supported by foamed nickel exhibits 99% conversion of HMF, 84% yield of FDCA, and 96% faradic efficiency. The NiO-N/C composite electrode is stable and remains active after six consecutive measurements. This work provides an effective method for the design and preparation of biomass energy electrocatalysts based on nitrogen-modulated NiO materials.
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2019
·
IF 7.723
Yunchao Feng,Wenlong Jia,Guihua Yan,Xianhai Zeng,Jonathan Sperry,Binbin Xu,Yong Sun,Xing Tang,Tingzhou Lei,Lu Lin
Directly oxidative esterification of Biomass-derived 5-hydroxymethylfurfural (HMF) into dimethyl furan dicarboxylate (DMFDCA) is a promising route for the replacement of petroleum-derived commodity chemical terephthalic acid (TPA) extensively employed in polyester synthesis. Co-based N-doped carbon materials are one of the most promising applied catalysts for oxidative esterification reaction, however, the active sites and reaction pathway of these catalysts have not been clearly clarified, which is crucial to the practical application. Herein, we report that ZIF-67 (a zeolitic imidazolate framework (ZIF)-type cobalt-containing MOF) derived Co@C-N material is a highly effective catalyst for the selective conversion of HMF into DMFDCA in 95% yield. The high activity of the ZIF-67 derived nanocarbon composites Co@C-N can be attributed to the electron transfer between nitrogen-doped carbon shells and Co nanoparticles. The appropriate graphitic N and pyridinic N doping increases the electronic mobility and active sites. Density functional theory (DFT) simulations indicated that oxygen, HMF and methanol molecules are adsorbed and activated on C-N materials. Furthermore, no 2, 5-diformylfuran (DFF) was captured as an intermediate because the oxidative esterification of aldehyde preferentially occurred than the oxidation of hydroxyl group in HMF. We anticipate that these results can drive progress in the bio-based polymers sector and oxidative esterification reaction.
研究领域:
生物质化学
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催化反应
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材料科学
·
理论计算
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DOI
高影响因子
POLYMER SCIENCE SERIES B
·
2014
·Vol. 56
·期 2
·148-153
·
IF 0.633
Wang Kemin,Lu Yuhui,Yin Ruixue,Jiang Yan,Yu Qiang
1,3-benzodioxole-5-yl-methyl-maleimide (BDOMM), a type of hydrogen-abstraction photoinitiator with both hydrogen donor and acceptor in one molecule for free radical photopolymerization, was synthesized through the reaction of piperonyl amine and maleic anhydride and characterized by IR, UV and 1H NMR spectroscopy. The results obtained indicated that the introduction of BDOMM could avoid the use of additional amine coinitiator, decrease the leachablity of photoinitiator and maintain high photo-initiation efficiency.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2022
·
IF 5.876
En-Hui Yuan,Meng Li,Ming-Hui Yang,Xiaosheng Huang,Kun Zhang,Weiliang Han,Zhicheng Tang,Zhong-Wen Liu
A direct hydrothermal synthesis strategy is developed to prepare the Cu–Fe-ZSM-5 zeolites by using the ethylenediaminetetraacetic acid disodium dihydrate (EDTA-2Na·2H 2 O) chelated Cu 2+ and Fe 3+ precursors as metal sources. During the crystallization, the metal chelates were spontaneously embedded into the ZSM-5 crystals and subsequently transformed to the zeolites encapsulated copper and iron species after removing the chelating agent via the high-temperature calcination . Rigorous characterizations indicate that the resulted Cu 2+ /Cu + and Fe 3+ /Fe 2+ species are formed ultra-small nano-composites with an average diameter of ∼2.2 nm and highly dispersed in the ZSM-5 zeolite crystals. The acidity of the ZSM-5 zeolites is subtly modulated by the encapsulated Cu–Fe nano-composite. As expected, the as-prepared Cu–Fe-ZSM-5 exhibits outstanding catalytic performance for the selective catalytic reduction of NO x with ammonia (NH 3 -SCR) in the broad reaction temperature ranges of 220–480 °C, which is much better than the Cu–Fe/ZSM-5 prepared with the conventional wetness impregnation method. Furthermore, the resultant zeolites show high stability and good tolerance to H 2 O and SO 2 , and it is very competitive for practical application to eliminate NO x . The developed one-pot hydrothermal synthesis route by using EDTA-2Na·2H 2 O as chelating agent is very convenient and easily reproducible, providing a general guideline to design and fabricate the superior transition metal modified zeolite catalysts for NH 3 -SCR and the related reactions.
研究领域:
催化
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2019
·Vol. 9
·期 15
·3933-3946
·
IF 5.726
Ting Wang,Yuebing Xu,Chengming Shi,Feng Jiang,Bing Liu,Xiaohao Liu
Direct conversion of syngas (CO/H2) into aromatics over tandem catalysts via the Fischer–Tropsch synthesis (FTS) route has attracted much attention because of its high one-pass conversion and milder reaction conditions. However, the complicated FTS product composition leads to more difficult mechanistic elucidation of aromatics formation compared to the methanol route. Herein, a series of strategies, such as covering external surface acid sites of HZSM-5 with a layer of inert SiO2, layered loading of an FeMn FTS catalyst and HZSM-5 zeolite in one reactor and two tandem reactors, and model reactions with ethylene and propylene over zeolite in a simulated FTS reaction environment, were applied to unveil the reaction mechanism and related factors affecting aromatic selectivity. It was found that different from the methanol route, the tandem FeMn–HZSM-5 catalyst produced aromatics mainly from the conversion of C5+ FT intermediates rather than light olefins (C2=–C4=). SiO2 coating could remarkably enhance the para-xylene (PX) selectivity due to hindering of its isomerization to major meta- and minor ortho-xylene (MX and OX) on the external surface acid sites of HZSM-5 by releasing the space confinement. The layered loading experiments in one reactor demonstrated that a farther distance from the FTS catalyst to zeolite largely increased the selectivity to BTX (benzene, toluene and xylene) in total aromatics from 48.3% to 68.9% on a carbon molar basis by suppressing the alkylation reaction of benzene and toluene with ethylene due to an obviously lower local ethylene concentration on HZSM-5. FeMn and HZSM-5 with layered loading in two tandem reactors confirmed that light olefins (C2=–C4=) were mainly hydrogenated and isomerized into paraffins. The model reactions with ethylene and propylene in a simulated local FTS reaction environment revealed that the presence of H2O and CO2in situ produced from the FTS reaction played a crucial role in promoting the aromatics formation at obviously lower reaction temperature which resulted from the enhancing acid strength and the driving H transfer to facilitate the cyclization and dehydrogenation reaction. This study provides a clear perspective for the aromatics formation mechanism and the tuning of the aromatic selectivity.
研究领域:
化学工程
·
催化科学
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DOI
高影响因子
TECHNOLOGY IN CANCER RESEARCH & TREATMENT
·
2020
·
IF 2.074
AiJun Huang,LiPing Chen,YiMing Wang,ShuQiang Ma,Song Jin,Hanzhou Cai,Xingzhong Huang,Hongbo Zhang,ZengRong Wang,Kun Lin,Fangsiyu Lin
Background:5-fluorouracil (5-FU) is a widely used drug for cancer treatment, but its effect and underlying mechanisms on osteosarcoma (OS) cells remain unclear.Methods:U2OS and MG63 cells were treated with 0, 50, 100, and 500 μM 5-FU. MTS and flow cytometry were used to examine the effect of 5-FU on cell viability and apoptosis, respectively. Circular RNA (circRNA) expression was detected using RNA sequencing and quantitative real-time PCR (qPCR). Differentially expressed circRNAs were further subjected to the Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) analysis to predict their functions. A circRNA–miRNA–mRNA interaction network was generated to analyze the regulatory networks of 5-FU–induced differentially expressed circRNAs. Western blotting (WB) was used to verify the protein in the downstream of circRNAs.Results:5-FU inhibited the cell viability of the MG63 cells in a concentration-dependent manner. The most significant effect was observed in the cells treated with 500 μM 5-FU. Apoptosis was also increased in the MG63 cells after 500 μM 5-FU treatment for 3 days. RNA sequencing results showed that 183 differentially expressed circRNAs (172 upregulated and 11 downregulated) in 5-FU–treated cells. KEGG and GO analysis showed that the differentially expressed circRNAs were primarily enriched in proliferation-, apoptosis-, and metabolism-related functions. qPCR was used to verify the most upregulated and downregulated circRNAs. The circRNA–miRNA–mRNA interaction network showed that these 8 circRNAs had a sizable regulatory network that links a series of genes involved in tumor suppression.Conclusion:5-FU treatment resulted in the differentially expressed circRNAs that were proliferation- and apoptosis-associated and were involved in the 5-FU–induced inhibition of tumor proliferation in OS cells.
研究领域:
肿瘤学
·
分子生物学
·
基因组学
·
癌症治疗
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Shijie Gu,Yingyue Cui,Kaihua Wen,Shimou Chen,Jianling Zhao
Layered lithium/manganese-rich oxides (LMR) receive much attention due to its high specific capacity (∼300 mAh g -1 ). However, the serious capacity degradation during cycling hinders the commercial application of the LMR. Herein, 3-cyano-5-fluorophenylboronic acid (CFBA) was applied as an electrolyte additive for enhancing the cycling stability of LMR at high voltage. Linear sweep voltammetry (LSV), density function theory (DFT) calculations and the initial charge d Q /d V profiles indicate that the preferential oxidation of CFBA can improve the oxidative stability of electrolyte. By adding 0.7 wt% CFBA into standard (STD) electrolyte (1 M LiPF 6 in EC :EMC:DMC = 1:1:1, by weight), the LMR/Li half-cell delivered a discharge capacity of 245 mAh g -1 with a capacity retention of 88.4% after 200 cycles at 0.5C, while only 68 mAh g -1 with 25.2% retention in STD electrolyte. Further characterizations and theoretical calculation illustrate that CFBA can effectively eliminate the harmful HF, which improve the electrochemical performance . More importantly, the CFBA participates in the formation of a thin and uniform protective cathode-electrolyte interface (CEI) film on the surface of LMR, which effectively suppresses electrolyte decomposition and protects the structural integrity of LMR.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
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