Precision Chemistry
·
2023
·
IF 0
Yating Lv,Hai Wang,Huixin Wu,Qingsong Luo,Liang Wang,Feng-Shou Xiao
Selective hydrogenation over earth-abundant metal catalysts is challenging but particularly valuable for practical applications in heterogeneous catalysis. Herein, we demonstrate that the catalytic selectivity of the commercial Raney nickel catalyst can be greatly tuned by modulation of the nickel surface by silica. Using quinoline hydrogenation as a model, we show that the silica-modified Raney nickel catalysts exhibit good activity, excellent selectivity, and long stability, whereas the undesired overhydrogenation reactions are effectively hindered. In contrast, the pristine Raney nickel catalyst shows inferior selectivity for the targeted product. Mechanistic studies confirm a positive role of silica to facilitate the desorption of 1,2,3,4-tetrahydroquinoline from the catalyst surface, thus enhancing the product selectivity.
研究领域:
物理化学
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材料科学
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催化化学
✓ 已验证
DOI
Catalysts
·
2016
·Vol. 6
·期 5
·63
·
IF 2.964
Yunfei Qi,Haiyun Yu,Quan Cao,Bo Dong,Xindong Mu,Aiqing Mao
Nickel is found to demonstrate high performance in the amination of cyclohexanol into cyclohexylamine in water and two solvents with low boiling points: tetrahydrofuran and cyclohexane. Three catalysts, Raney Ni, Ni/Al2O3and Ni/C, were investigated and it is found that the base, hydrogen, the solvents and the support will affect the activity of the catalyst. In water, all the three catalysts achieved over 85% conversion and 90% cyclohexylamine selectivity in the presence of base and hydrogen at a high temperature. In tetrahydrofuran and cyclohexane, Ni/Al2O3exhibits better activity than Ni/C under optimal conditions. Ni/C was stable during recycling in aqueous ammonia, while Ni/Al2O3was not due to the formation of AlO(OH).Keywords:nickel;cyclohexanol;cyclohexylamine;base;hydrogen
研究领域:
化学工程
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催化
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2017
·
IF 3.615
Tingting Xu,Xudong Hou,Shengjun Liu,Bo Liu
We demonstrated a facile and efficient method for the preparation of a magnetic and porous Ni@MOF-74(Ni) [Ni 2 (DOBDC), DOBDC = 2, 5-dihydroxyterephthalate] composite by one-step solvothermal reaction of Raney Ni and DOBDC. Ni in the reaction not only acted as the core of the composite, but also provided metal source for the formation of MOF-74(Ni). The Ni@MOF-74(Ni) composite exhibits both magnetic characteristics and high porosity, enabling it an efficient candidate for dye removal and target drug delivery system. The adsorption amount of rhodamine b reached up to 177.8 mg g −1 , and 4.1 mg g −1 for ibuprofen.
研究领域:
材料科学
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化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Weilai Wang,Junfeng Niu,Zhifeng Yang
Presence of unsaturated bonds and halogen-containing groups is the most common characteristic of toxic and harmful environmental pollutants. Herein, catalytic hydrogenation was chosen as a water quality control method for such contaminants. Considering the safety, availability and activity of the hydrogen source, electrochemical in situ hydrogen generation was introduced. Under the combined action of Raney Ni (R-Ni) and nascent hydrogen (Nas-H 2 ), three compounds (50 mg L −1 , 90 ml), i.e., acrylamide, 2, 6-dibromo-4-nitrophenol and 2-chloro-4-fluorobenzonitrile achieved complete hydrogenation reduction in a short time. The improved system realized the quantitative consumption of hydrogen source and the efficient operation of hydrogenation reaction under mild conditions. Additionally, the alkaline environment formed by hydrogen evolution reaction (HER) avoided secondary pollution caused by catalyst dissolution. Atomic hydrogen (H·) produced from R-Ni and Nas-H 2 was the active free radical of the reaction. The hydrogenation activities of different functional groups were obtained according to the following order: Ph-NO 2 ＞ -C = C- ＞ Ph-C≡N ＞ Ph-Br ＞ Ph-Cl ＞ Ph-F. This work indicates that the catalytic hydrogenation system consisting of R-Ni and Nas-H 2 is a promising technology to reduce unsaturated bonds and halogen-containing groups.
研究领域:
环境科学
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化学工程
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催化
·
水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2021
·
IF 10.618
Lu Cao,Hongguang Liu,Wenjun Xie,Shumeng Jiao,Xueqiang Wu,Kaisong Yuan,Xia Zhou,Muzi Yang,Yanyan Guan,Huaihong Cai,Zhihui Lai,Jian Chen,Haibo Zhou
With the increasing number of reports on aristolochic acid I (AAI), more and more toxic and side effects have been discovered successively. The main recognized carcinogenic mechanism is that AAI is metabolized into aristololactam I (AAT) in the body by nitroreductases , ultimately forming AAT-DNA adducts that cause disease. However, the carcinogenic mechanism is still not well understood by currently reported indirect method, there has always been a great demand to develop a direct method for real-time monitoring such process. In this work, surface-enhanced Raman spectroscopy (SERS) was used for the first time to monitor the process of AAI under the action of reducing agent sodium borohydride and catalyst Raney nickel to form AAT. We first found the abundant intermediate product-amino derivative of AAI, which was never reported before by other methods. The AAT was then obtained by a one-step dehydration reaction from the amino derivative of AAI under such reduction conditions. The product of amino derivative of AAI and AAT were further verified by thin-layer chromatography, H nuclear magnetic resonance spectra , mass spectrometry, and ultra-high performance liquid chromatography. Furthermore, a density functional theory-supported in-depth vibrational characterization of AAI and AAT was performed. The monitoring of the AAI reduction process by SERS can be of great significance for further exploration of its pathogenic mechanism, prevention, and monitoring of “nephropathy” and other diseases caused by AAI.
研究领域:
分析化学
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毒理学
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药理学
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计算化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2017
·
IF 3.091
Yu-Lu Wang,Ji-Feng Zheng,Shuai Yan,Yue-Yuan Ye,Shui-Rong Li,Duo Wang,Yun-Quan Liu
A novel liquefaction method was developed for transforming different types of biomass, such as fir, bamboo, pine, and corncob, into bio-oil efficiently with Raney nickel (R-Ni) and NaOH as combined catalysts in a 2-propanol/H2O system, which was carried out in a 50 mL stainless-steel autoclave at 245 °C, corresponding to the working pressure maintained at 8 MPa. The conversion of biomass could reach 97–99%. Besides, a high bio-oil yield of 63.98% and higher heating value of 30.09 MJ/kg were achieved when fir was used as the feedstock. The gas chromatography–mass spectrometry analyses indicated that the major compounds in bio-oils were phenols, followed by acids, alcohols, ketones, and hydrocarbons, which were mainly light-weighted molecules with low boiling points measured by thermogravimetric analysis. Additionally, the R-Ni catalyst could be repeatedly used at least 5 times without the loss of activity.
研究领域:
化学工程
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生物能源
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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
AICHE JOURNAL
·
2023
·Vol. 69
·期 7
·e18056
·
IF 3.7
Haoan Fan,Bolong Li,Xuezhi Zhao,Zhecheng Fang,Chao Chen,Wenhua Zhou,Wulong Yang,Mian Li,Xiuyang Lu,Jie Fu
The kinetics and mechanisms of selective maltose hydrogenation over Raney Ni remain poorly understood, which hinders the industrial advancement of maltitol production for biorefining. Herein, the impact of hydrogenation conditions and in-depth mechanistic characterizations were carefully investigated in this research. Optimization of reaction conditions illustrated that maltitol formation was favored by moderate reaction temperatures (≤130°C), high hydrogen pressures (>7 MPa), and near-neutral sodium phosphate buffer (pH = 6.47). Kinetic studies demonstrated the E a of 45.5 kJ/mol for the hydrogenation of maltose. The in situ IR revealed that the hydrogenation of maltose over Raney Ni occurs in the order of ring opening and adsorption via CO of the aldose form followed by hydrogenation. The UV–vis spectra demonstrated the near-neutral setting (pH = 6.47) promoted the production of open-chain aldose conformation and selective CO hydrogenation to the corresponding alcohols. The present study on concentrated-maltose hydrogenation paves the way for the industrial development of maltitol manufacturing.
研究领域:
化学工程
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催化
·
生物化工
✓ 已验证
产品关联
DOI
高影响因子
Biotechnology for Biofuels and Bioproducts
·
2024
·Vol. 17
·期 1
·1-13
·
IF 3.3
Wu Yilu,Su Changsheng,Liao Zicheng,Zhang Gege,Jiang Yongjie,Wang Yankun,Zhang Changwei,Cai Di,Qin Peiyong,Tan Tianwei
Background The effective valorization of lignin and carbohydrates in lignocellulose matrix under the concept of biorefinery is a primary strategy to produce sustainable chemicals and fuels. Based on the reductive catalytic fractionation (RCF), lignin in lignocelluloses can be depolymerized into viscous oils, while the highly delignified pulps with high polysaccharides retention can be transformed into various chemicals. Results A biorefinery paradigm for sequentially valorization of the main components in poplar sawdust was constructed. In this process, the well-defined low-molecular-weight phenols and bioethanol were co-generated by tandem chemo-catalysis in the RCF stage and bio-catalysis in fermentation stage. In the RCF stage, hydrogen transfer reactions were conducted in one-pot process using Raney Ni as catalyst, while the isopropanol (2-PrOH) in the initial liquor was served as a hydrogen donor and the solvent for lignin dissolution. Results indicated the proportion of the 2-PrOH in the initial liquor of RCF influenced the chemical constitution and yield of the lignin oil, which also affected the characteristics of the pulps and the following bioethanol production. A 67.48 ± 0.44% delignification with 20.65 ± 0.31% of monolignols yield were realized when the 2-PrOH:H 2 O ratio in initial liquor was 7:3 (6.67 wt% of the catalyst loading, 200 °C for 3 h). The RCF pulp had higher carbohydrates retention (57.96 ± 2.78 wt%), which was converted to 21.61 ± 0.62 g/L of bioethanol with a yield of 0.429 ± 0.010 g/g in fermentation using an engineered S. cerevisiae strain. Based on the mass balance analysis, 104.4 g of ethanol and 206.5 g of lignin oil can be produced from 1000 g of the raw poplar sawdust. Conclusions The main chemical components in poplar sawdust can be effectively transformed into lignin oil and bioethanol. The attractive results from the biorefinery process exhibit great promise for the production of valuable biofuels and chemicals from abundant lignocellulosic materials.
研究领域:
生物技术
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化学工程
·
生化工程
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可再生能源
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhe-Hui Zhang,Meng-Ying Liu,Zhuohua Sun,Katalin Barta,Tong-Qi Yuan
Funneling complex lignocellulose into simple and valuable building blocks has garnered significant interest in the field of biorefinery as a competitor to the petrochemical industry. Reductive Catalytic Fractionation (RCF) of lignocellulose, an innovative biorefinery technology, provides a promising strategy for complete valorization of lignocellulose into various valuable chemicals. In this study, integrated processes utilizing RCF strategies were developed to achieve complete conversion of lignocellulose into various simple and valuable platform chemicals. The core of this system is the flexible use of commercial Ni catalysts including Raney Ni and Ni/SiO 2 -Al 2 O 3 which brings great benefits for future upscale and industrial applications. Surprisingly, both monomers derived from lignin and high molecular weight fractions could be converted to 4-ethylcyclohexanol while carbohydrate pulp was converted to furfural and 5-methoxymethylfurfural (MMF) in one-pot. MMF could be further upgraded to 2,5-Furandicarboxylicacid (FDCA) via catalytic oxidation by Ru/C catalysts. This work could inspire the development of more sustainable and economically viable biorefinery processes.
研究领域:
生物精炼
·
化学工程
·
催化
·
可持续化学
✓ 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）