RSC Advances
·
2016
·Vol. 6
·期 19
·15354-15361
·
IF 3.289
Xinhuan Lu,Yang chen,Zhenshuang Zhao,Hao Deng,Dan Zhou,Changcheng Wei,Renfeng Nie,Qinghua Xia
The carbon supported 10% Ni catalysts doped with 3‰ Rh have been prepared by an impregnation method. These catalysts have been used to catalyze the one-step hydrogenation of nitrobenzene to cyclohexylamine. The results show that the 3‰ Rh–10% Ni/CSC (biocarbon) catalyst exhibits an excellent performance to achieve 100 mol% conversion of nitrobenzene and 91.6% selectivity of cyclohexylamine under reaction conditions of 3.5 MPa and 140 °C. The recycling tests reveal recyclable stability of 3‰ Rh–10% Ni/CSC. This catalyst is active for the hydrogenation of a series of electron-deficient nitrobenzenes. Some factors such as the type of carriers, the content of Ni and Rh, the type of metals and additives play important roles in controlling the selective hydrogenation.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jiale Wu,Jiajun Zhang,Liguo Wang,Ziqiang Han,Xiang Hui,Yan Cao,Jianhui Shi,Shuang Xu,Peng He,Huiquan Li
Green production of alicyclic amines is highly desirable but of great challenges. Herein, an efficient one-pot synthesis of alicyclic amines from nitroaromatics was realized with a Pt-Ru bimetallic catalyst. 0.5 %Pt-2.5 %Ru supported on an air-exfoliated C 3 N 4 nanosheet achieved 100.0 % conversion of nitrobenzene (NB) with 98.9 % selectivity of cyclohexylamine (CHA) under mild conditions of 80 °C and 1 MPa, attaining a yield rate for alicyclic amine of 357.9 mmol/g metal ·h. Our study has shown hydrogenation of nitro group and aromatic ring took place in sequence over Pt and Ru in a tandem manner due to the highly selective adsorption. During the hydrogenation, the homolytic dissociation of H 2 occurred on the bimetal sites and the inter-site hydrogen spillover between the bimetal played a crucial role. C 3 N 4 nanosheet as the support not only gave rise to the uniform dispersion of metal nanoparticles, but was crucial in curbing the unnecessary adsorption of intermediate aromatic amines. Our study has also demonstrated the good stability and wide applicability of the Pt-Ru/C 3 N 4 -air catalyst for the hydrogenation of various nitroaromatic derivatives.
研究领域:
催化化学
·
绿色化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2018
·Vol. 36
·期 12
·1191-1196
·
IF 2.378
Xuefeng Li,Zhe Wang,Shanjun Mao,Yiqing Chen,Minghui Tang,Haoran Li,Yong Wang
Cyclohexylamine is a versatile intermediate in various chemical industries, which can be expediently synthesized via hydrogenation of aniline or nitrobenzene. However, such processes always suffer from side reactions. Many reports have found that specific additives can suppress the formation of side products, but the mechanism is still not clear. In this work, results suggest that it is the hydroxide ion of alkali metal hydroxides, rather than the cations, which plays a key role in suppressing the side reactions on supported Ru-based catalysts. With the assistance of LiOH, the selectivity toward cyclohexylamine increased from 85.4% to 100%. Side products, such as dicyclohexylamine, cyclohexanol and N -isopropyl cyclohexylamine, could no longer be detected. Theoretical calculations further disclosed that addition of alkali metal hydroxides inhibited the dissociation of enamine and decreased the adsorption energy of cyclohexylamine, which might be the reasons for a better selectivity. However, the addition of alkali metal hydroxides reduced the activity of nitrobenzene hydrogenation by unfolding the condensation reaction route. To recover or even further enhance the catalytic performance, a second metal component was introduced and the resultant RuNi/AC exhibited a significant improvement in activity compared with Ru/AC.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
PEST MANAGEMENT SCIENCE
·
2020
·Vol. 76
·期 8
·2711-2719
·
IF 3.75
Xingan Cheng,Huiqing He,Wen-Xiong Wang,Fangyun Dong,Hanhui Zhang,Jingmin Ye,Chuncan Tan,Yuehua Wu,Xiaojing Lv,Xuhong Jiang,Xiangjing Qin
BACKGROUND Matrine is an important traditional plant-derived insecticide with broad-spectrum activity. However, due to its moderate activity, matrine is mainly applied in combination with other pesticides. In order to discover new potential natural-product-based crop protection agents, a series of matrine derivatives characterized by cyclohexylamine group were synthesized to screen their insecticidal activity against seven typically agricultural pests. RESULTS The structural configurations of compounds were characterized by IR, 1 H NMR, 13 C NMR, MS and XRD, with the pure yields of 42%, 65% and 71%, respectively. Although all compounds showed poor insecticidal activity against five lepidoptera pests, the compounds 2 and 4 displayed remarkable insecticidal activities against Lipaphis erysimi and Mulberry Root-Knot Nematode with a concentration-dependent manner within 0.5~1.5 mg/ mL. Compared with matrine (60%), compounds 2 and 4 exhibited potent insecticidal activities against L. erysimi , with a corrected mortality of 83.3% and 89.7%, respectively. They also showed excellent control effects on Mulberry Root-Knot Nematode , with corrected mortality as high as 88% and 80%, respectively. CONCLUSION All four synthesized matrine derivatives showed poor insecticidal activity against five lepidoptera pests, but the compounds 2 and 4 exhibited much stronger insecticidal activities against L. erysimi and Mulberry Root-Knot Nematode than matrine. Combined with the structural characteristics of compounds 1~4, we conclude that 4-methylcyclohexylamine, not the carbon disulfide group or cyclohexylamine group alone, mainly contributed to the improvement of insecticidal activities of matrine derivatives against these two agricultural pests. This work provides a direction and foundation for structural optimization of the matrine pesticides in the future. © 2020 Society of Chemical Industry
研究领域:
植物化学
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农业科学
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有机化学
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产品关联
DOI
PubMed
高影响因子
COMBUSTION AND FLAME
·
2023
·
IF 4.4
Jinhu Liang,Chen Zhao,Ziwen Zhao,Xinhui Wang,Ming-Xu Jia,Quan-De Wang,Yang Zhang,Fengqi Zhao
Amine compounds are an important class of nitro-containing fuels and represent as promising renewable fuels . However, the structural effect from the alkyl group on the combustion characteristics of amines remains an urgent problem to promote their usage in practical engines. To probe and replenish the combustion properties of amine fuels, this work reported an experimental and kinetic modeling study on the high-temperature ignition and pyrolysis characteristics of cyclohexylamine over a wide range of conditions. Specifically, a high-pressure shock tube is used to measure the ignition delay times under the temperature range from 1100 K to 1700 K with pressure of 2 and 5 bar and the equivalence ratios of 0.5, 1.0 and 2.0. The pyrolysis characteristics is studied using a single-pulse shock tube at fuel concentration of 0.5% diluted by argon in the temperature range 950–1400 K at 5 and 10 bar with the residence time around 1.6 microsecond . A detailed kinetic mechanism is developed to simulate the experimental results. To improve the accuracy of the detailed mechanism, primary initial reactions of cyclohexylamine including the hydrogen abstraction reactions and the C N decomposition reaction are theoretically studied at G4//M06–2X/6–311++ G (d, p) level of theory with transition state theory and RRKM/mater equation. The detailed kinetic mechanism shows good prediction accuracy of the ignition delay times and pyrolysis product distributions under different temperature, pressure and equivalence ratio conditions. Sensitivity analysis results indicate that the most sensitive reaction is O 2 + H = O + OH with the most negative sensitivity coefficient and the abstraction reaction of vinylamine with OH radical, C 2 H 3 NH 2 + OH = C 2 H 3 NH + H 2 O also exhibits large sensitivity coefficients. Reaction path analysis reveals that the abstraction reactions control the initial oxidation of cyclohexylamine and cyclohexen-1-amine, cyclohexen-2-amine, and cyclohexen-3-amine are also major intermediates during the oxidation of cyclohexylamine besides small pyrolysis products.
研究领域:
能源科学
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化学工程
·
燃烧学
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-11
·
IF 4.259
Lu Xinhuan,He Jie,Jing Run,Tao Peipei,Nie Renfeng,Zhou Dan,Xia Qinghua
Biocarbon supported Ni catalysts have been prepared by facile impregnation of Ni species by microwave-heating and used for selective hydrogenation of nitrobenzene to cyclohexylamine. These catalysts were characterized by X-ray diffraction, Raman spectra, N2 sorption measurement, X-ray photoelectron spectroscopy, temperature programmed reduction of H2 and H2 temperature-programmed desorption. The morphology and particle size of catalysts were imaged by scanning electron microscope and transmission electron microscope. For the hydrogenation of nitrobenzene to cyclohexylamine, 10%Ni/CSC-II(b) exhibits the best catalytic activity to achieve 100 mol% conversion of nitrobenzene and 96.7% selectivity of cyclohexylamine under reaction conditions of 2.0 MPa H2 and 200 °C, ascribed to high dispersion of Ni species and formation of nanosized Ni particles on the support aided by microwave-heating. Thus-prepared Ni/CSC catalyst is greatly activated, in which the addition of precious metal like Rh is totally avoided.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
WATER SCIENCE AND TECHNOLOGY
·
2021
·Vol. 83
·期 9
·2160-2168
·
IF 1.915
Feng Kaiqing,Zhang Jiandong,Gao Lili,Tian Qi
Alicyclic amines are widely used in several types of industries, and considerable attention has been devoted to possible environmental pollution by alicyclic amines in hypersaline industrial wastewater. In this study, a new hypersaline tolerant bacterial TYUT067 capable of growing in liquid basal salt medium with cyclohexylamine (CHAM) as the sole carbon source and energy source, was isolated from soil, and discovered with highly efficient CHAM degrading ability. The strain TYUT067 was identified as Paenarthrobacter sp. based on 16S rDNA gene sequence, and its degradation characteristic was examined. The results revealed that the isolated TYUT067 could grow well under pH range of 6.5–10.0, temperature from 20 °C to 30 °C. For degradation of 60 mM of cyclohexylamine, 100% degradation could be finished within 120 h. The TYUT067 could degrade 10 mM CHAM under hypersaline conditions (3–5% NaCl, w/v), revealed the hypersaline tolerance of TYUT067. Different type of amines was also tested with TYUT067, the degradations of >90% were achieved toward several alicyclic amines. The current results suggested that TYUT067 was a potential species could be efficiently used for the degradation of alicyclic amines and might be applicable to a hypersaline wastewater treatment system for the removal of alicyclic amines. A new cyclohexylamine degradation bacterial strain TYUT067 was isolated from soil environment. The isolated TYUT067 is an alkali-tolerant strain and mesophilic microorganisms. The isolated TYUT067 can degrade CHAM under hypersaline environment. The isolated TYUT067 can degrade various alicyclic amines.
研究领域:
环境微生物学
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环境工程
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生物降解
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工业废水处理
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污染生态学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2019
·
IF 2.29
Jian Wang,Yongqin Du,Cunbin Du,Anli Xu,Ganbing Yao,Hongkun Zhao,Xuedong Zhu,Xuhong Guo
For switchable hydrophilicity solvent (SHS) systems ( N,N -Dimethylcyclohexylamine (DMCA), water, and carbon dioxide): the density, viscosity, refractive index and conductivity at (283.15–308.15) K and 0.1 Mpa, were measured. The apparent molar volumes were determined as a function of composition at each temperature from experimental data. Based on Masson’s equation limiting apparent molar volumes and Masson’s coefficient S V describing the character of interactions were calculated. The relative viscosity values were adjusted to obtain the viscosity B coefficients and dB/dT values. It has been observed that there exist strong solute-solvent and solute-solute interactions in these systems, and DMCAH-bicarbonate salt acts as structure-maker in aqueous solvent.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2019
·
IF 2.29
Dan Zhao,Yun Zhuang,Chunshan Fan,Fang Yang,Yuhuan Chen,Xihui Zhang
Surface tension ( γ ) for five binary mixtures containing N, N-dimethylcyclohexylamine (DMCA) and alcohol, ethanol, n-propanol, iso -propanol, n-butanol or iso -butanol were measured over the whole range of composition at 0.1 MPa and different temperatures ranging from (288.15 to 308.15) K. From the experimental data, the surface tension deviations ( δγ ) for the binary mixtures were calculated. The δγ values are positive for all the studied systems and increase with the decreasing of alky chain length of alcohol. For the mixture containing the branched alkyl alcohol, the increase is significant compared with the equivalent molecules with straight chains. According to temperature dependence of surface tension, the thermodynamic parameters, surface enthalpy ( H γ ) and surface entropy ( S γ ) were also estimated and further discussed.
研究领域:
物理化学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 3
·2024-2035
·
IF 3.9
Jiale Wu,Liguo Wang,Shuang Xu,Yan Cao,Ziqiang Han,Huiquan Li
Developing efficient and green catalytic systems is highly desired in the syntheses of alicyclic amines via hydrogenation of nitroaromatics. Herein, we developed Ru–Pd dual active site catalysts in which Ru and Pd species were anchored and highly dispersed on air-exfoliated carbon nitride (Ru–Pd/C3N4-air). As-prepared catalysts were employed in the hydrogenation of nitrobenzene (NB) to cyclohexylamine (CHA). Compared with single Ru or Pd based catalysts, Ru–Pd dual active site catalysts obtained a higher CHA production rate of 26.7 mol CHA mol−1 Ru·Pd h−1 at 80 °C and 3 MPa H2. The activation energy for the hydrogenation of the nitro group and benzene ring was calculated as 26.26 kJ mol−1 and 66.30 kJ mol−1, respectively. Intrinsic kinetic studies demonstrated that Pd was the dominant metal for hydrogenation of nitro group, while Ru was dominant for benzene ring. Thereinto, the corresponding non-dominant metals enhanced activation and dissociation of H2, thereby improving catalytic activity significantly. This excellent performance of Ru–Pd catalysts could be attributed to highly dispersed Ru–Nx and Pd–Nx at a nanoscale distance, which was conducive to metal-assisted hydrogenation. Stability investigation showed that the performance of Ru–Pd catalysts could be essentially maintained at a high level. Additionally, the substrate scope could be successfully extended to hydrogenation of other nitroaromatics with different substituents.
研究领域:
催化化学
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绿色化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2020
·
IF 2.369
Dan Zhao,Yun Zhuang,Chunshan Fan,Xihui Zhang,Fang Yang,Yuhuan Chen
The densities of six binary systems containing N,N-dimethylcyclohexylamine (DMCA) and ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, or tert-butanol were reported in this work at temperatures ranging from (288.15 to 318.15) K and atmospheric pressure. According to the experimental density values, molar volume (Vm), thermal expansion coefficient (αp), and excess molar volume (VmE) were calculated. The results showed that VmE values were all negative over the entire composition. The minimum values of the six systems at 298.15 K were located at (−1.097, −1.094, −0.900, −1.033, −1.154, and −1.073) cm3·mol–1 at about xDMCA = 0.4, respectively. All these are dependent on intermolecular interactions and the steric structural effect. Furthermore, VmE variations with composition (xDMCA) as well as temperature were well fitted with the Redlich–Kister-type polynomial equation.
研究领域:
物理化学
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热力学
✓ 已验证
DOI
高影响因子
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
·
催化
·
有机化学
✓ 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）