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增材制造 5

光催化 2

激光选区熔化 2

电子束 2

选区激光熔化 2

选择性激光熔化 2

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4-二硝基茴香醚 1

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HEMTs）；栅槽；数字湿法腐蚀；选择性湿法腐蚀 1

MOF基催化剂 1

P4 1

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一氧化碳氧化 1

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Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selectivecatalytic oxidation of cyclohexane

《化学科学与工程前沿（英文）》 2022年 第16卷 第8期   页码 1211-1223 doi: 10.1007/s11705-022-2145-3

摘要： The one-step highly selective oxidation of cyclohexane into cyclohexanone and cyclohexanol as the essential intermediates of nylon-6 and nylon-66 is considerably challenging. Therefore, an efficient and low-cost catalyst must be urgently developed to improve the efficiency of this process. In this study, a Co3O4–CeO2 composite oxide catalyst was successfully prepared through ultrasound-assisted co-precipitation. This catalyst exhibited a higher selectivity to KA-oil, which was benefited from the synergistic effects between Co3+/Co2+ and Ce4+/Ce3+ redox pairs, than bulk CeO2 and/or Co3O4. Under the optimum reaction conditions, 89.6% selectivity to KA-oil with a cyclohexane conversion of 5.8% was achieved over Co3O4–CeO2. Its catalytic performance remained unchanged after five runs. Using the synergistic effects between the redox pairs of different transition metals, this study provides a feasible strategy to design high-performance catalysts for the selective oxidation of alkanes.

关键词： Co3O4–CeO2 composite oxides     cyclohexanone     cyclohexanol     ultrasonic-assisted co-precipitation     selective oxidation     solvent-free    

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Studies on QSAR of metalloporphyrin catalysts in the oxidation of cyclohexane to adipic acid

CHEN Yixia, SHE Yuanbin, XU Jing, LI Yan

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 155-161 doi: 10.1007/s11705-007-0029-1

摘要： The catalysis of chloridized metalloporphyrins in the oxidation of cyclohexane to adipic acid was systematically investigated. The turnover numbers (TON) data of 19 catalysts were obtained experimentally under optimal reaction conditions, and 2.4?10 TON for T(-Cl)PP-MnCl catalyst at 2.0?10 mol/L of dosage was reached under the conditions of dioxygen pressure of 2.5 MPa at 150?C for 4 h. This was the best result reported for this reaction up to now. The QSAR models for each concerned metalloporphyrin were established, where the catalytic activity was significantly correlated with the (the energy level of the lowest unoccupied molecule orbit) and L (the bond length between metal-nitrogen atoms). Using the QSAR models, four new metalloporphyrins with substituted nitro group were designed, and their catalytic activities were predicted. The experimental TON data of newly designed porphyrins were in good agreement with the predicted ones, and the square of their correlation coefficient was more than 0.958. The above results demonstrated that the proposed structure-activity relationship model could be applied to design some new metalloporphyrin catalysts, and to predict their catalytic activity in cyclohexane oxidation.

关键词： cyclohexane     concerned metalloporphyrin     structure-activity relationship     metal-nitrogen     oxidation    

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Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

《化学科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 369-377 doi: 10.1007/s11705-014-1435-9

摘要： Catalysts Pt/TiO and NiMo/Al O are highly active and selective for the hydrodeoxygenation of guaiacol in a fixed bed reactor at 300 °C and 7.1 MPa, leading to the hydrogenation of aromatic ring, followed by demethylation and dehydroxylation to produce cyclohexane. For a complete hydrodeoxygenation of guaiacol, metal sites and acid sites are required. NiMo/Al O and Pt/Al O are more active and selective for cyclohexane formation as compared with Pt/TiO at 285 °C and 4 MPa. However, Pt/TiO is stable while the other two catalysts deactivate due to the nature and amount of coke formation during the reaction.

关键词： Pt/TiO2     NiMo/Al2O3     Pt/Al2O3     bio-oil     hydrodeoxygenation     guaiacol     cyclohexane    

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Advances and perspectives in catalysts for liquid-phase oxidation of cyclohexane

Hui LI, Yuanbin SHE, Tao WANG

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 356-368 doi: 10.1007/s11705-012-0903-3

摘要： The latest progress and developments in catalysts for the oxidation of cyclohexane are reviewed. Catalytic systems for the oxidation of cyclohexane including metal supported, metal oxides, molecular sieves, metal substituted polyoxometalates, photocatalysts, organocatalysts, Gif systems, metal-organic catalysts and metalloporphyrins are discussed with a particular emphasis on metalloporphyrin catalytic systems. The advantages and disadvantages of these methods are summarized and analyzed. Finally, the development trends in the oxidation technology of cyclohexane are examined.

关键词： cyclohexane     liquid-phase oxidation     catalysis    

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Transition metal-doped heteropoly catalysts for the selective oxidation of methacrolein to methacrylic

Yanxia Zheng,Heng Zhang,Lei Wang,Suojiang Zhang,Shaojun Wang

《化学科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 139-146 doi: 10.1007/s11705-015-1548-9

摘要： Heteropoly compounds with the general formula Cs M H P Mo VO (M= Fe, Co, Ni, Cu or Zn) and Cs Cu H P Mo VO ( = 0.1, 0.3 or 0.7) were synthesized and then used as catalysts for the selective oxidation of methacrolein to methacrylic acid. The effects of the transition metals on the structure and activity of the catalysts were investigated. FTIR spectra showed that the transition metal-doped catalysts maintained the Keggin structure of the undoped catalysts. X-ray diffraction results indicated that before calcination, the catalysts doped with Fe and Cu had cubic secondary structures, while the catalysts doped with Co, Ni or Zn had both triclinic and cubic phases and the Co-doped catalyst had the highest content of the triclinic form. Thermal treatment can decrease the content of the triclinic phase. NH temperature-programmed desorption and H temperature-programmed reduction results showed that the transition metals changed the acid and redox properties of the catalysts. The addition of Fe or Cu had positive effects on the activities of the catalyst which is due to the improvement of the electron transfer between the Fe or Cu and the Mo. The effects of the copper content on structure and catalytic activity were also investigated. The Cs Cu H P Mo VO catalyst had the best performance for the selective oxidation of methacrolein to methacrylic acid.

关键词： heteropoly compounds     transition metals     selective oxidation     methacrolein    

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Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

《环境科学与工程前沿（英文）》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1557-0

摘要：

● A series of Cu-ZSM-5 catalysts were tested for DMF selective catalytic oxidation.

关键词： N     N-Dimethylformamide     Selective catalytic oxidation     Cu-ZSM-5     CuO particle size    

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β-Cyclodextrin promoted oxidation of primary amines to nitriles in water

Dongpo SHI, Hongbing JI, Zhong LI

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 196-200 doi: 10.1007/s11705-009-0051-6

摘要： A facile, efficient and substrate-selective oxidation of the primary amines with NaClO as oxidant catalyzed by cyclodextrin ( CD) has been developed in water for the first time, and the behavior of cyclodextrin that catalyzed the primary amines to nitriles in water was investigated. It was found that the primary amines which could form host-guest complexes with cyclodextrin were oxidized to nitriles with excellent yields at ambient temperature. The results show that cyclodextrin worked not only as a solubilizing agent but also as a catalyst in these reactions.

关键词： substrate-selective     amines oxidation     β-cyclodextrin    

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Selective oxidation of o -nitrotoluene to o -nitrobenzaldehyde with metalloporphyrins as biomimetic catalysts

Xinling WANG, Yuanbin SHE,

《化学科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 453-456 doi: 10.1007/s11705-009-0167-8

摘要： Selective oxidation of -nitrotoluene to -nitrobenzaldehyde with metalloporphyrins as biomimetic catalysts was studied. The peripheral substituent around porphyrin rings and various process parameters of NaOH concentration, reaction temperature, reaction time and oxygen pressure all affect the selectivity of -nitrobenzaldehyde. Further, 82.0% selectivity of -nitrobenzaldehyde was achieved under the optimum conditions: 1.0×10mol•L of T(-NO)PPFeCl catalyst, 2.5mol•L of NaOH, 0.2mol•L of -nitrotoluene, 45°C and 2.0MPa for 6h.

关键词： -nitrobenzaldehyde     temperature     biomimetic     selectivity     pressure    

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Enhancing the aromatic selectivity of cyclohexane aromatization by CO2 coupling

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1801-1808 doi: 10.1007/s11705-023-2325-9

摘要： Improving the aromatic selectivity in the alkane aromatization process is of great importance for its practical utilization but challenge to make because the high H/C ratio of alkanes would lead to a serious hydrogen transfer process and a large amount of light alkanes. Herein, CO2 is introduced into the cyclohexane conversion process on the HZSM-5 zeolite, which can improve the aromatic selectivity. By optimizing the reaction conditions, an improved aromatic (benzene, toluene, xylene, and C9+) selectivity of 48.2% can be obtained at the conditions of 2.7 MPa (CO2), 450 °C, and 1.7 h−1, which is better than that without CO2 (aromatic selectivity = 43.2%). In situ transmission Fourier transform infrared spectroscopy spectra illustrate that many oxygenated chemical intermediates (e.g., carboxylic acid, anhydride, unsaturated aldehydes/ketones or ketene) would be formed during the cyclohexane conversion process in the presence of CO2. 13C isotope labeling experimental results demonstrate that CO2 can enter into the aromatics through the formation of oxygenated chemical intermediates and thereby improve the aromatic selectivity. This study may open a green, economic, and promising way to improve the aromatic selectivity for alkane aromatization process.

关键词： aromatics     carbon dioxide     aromatization     coupling reaction     ZSM-5 zeolite    

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Efficient base-free oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid over copper-doped

Feng Cheng, Dongwen Guo, Jinhua Lai, Meihui Long, Wenguang Zhao, Xianxiang Liu, Dulin Yin

《化学科学与工程前沿（英文）》 2021年 第15卷 第4期   页码 960-968 doi: 10.1007/s11705-020-1999-5

摘要： 2,5-Furandicarboxylic acid (FDCA) is an important and renewable building block and can serve as an alternative to terephthalic acid in the production of bio-based degradable plastic. In this study, Cu-doped MnO  nanorods were prepared by a facile hydrothermal redox method and employed as catalysts for the selective oxidation of 5-hydroxymethylfurfural (HMF) to FDCA using -butyl hydroperoxide (TBHP) as an oxidant. The catalysts were characterized using X-ray diffraction analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, and transmission electron microscopy. The effects of oxidants, solvents, and reaction conditions on the oxidation of HMF were investigated, and a reaction mechanism was proposed. Experimental results demonstrated that 99.4% conversion of HMF and 96.3% selectivity of FDCA were obtained under suitable conditions, and -butanol was the most suitable solvent when TBHP was used as an oxidant. More importantly, the Cu-doped MnO catalyst can maintain durable catalytic activity after being recycled for more than ten times.

关键词： 5-hydroxymethylfurfural     25-furandicarboxylic acid     selective oxidation     Cu-doped MnO2     biomass transformation    

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Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

《化学科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 142-153 doi: 10.1007/s11705-015-1516-4

摘要： Recent advances with Pd containing catalysts for the selective hydrogenation of acetylene are described. The overview classifies enhancement of catalytic properties for monometallic and bimetallic Pd catalysts. Activity/selectivity of Pd catalysts can be modified by controlling particle shape/morphology or immobilisation on a support which interacts strongly with Pd particles. In both cases enhanced ethylene selectivity is generally associated with modifying ethylene adsorption strength and/or changes to hydride formation. Inorganic and organic selectivity modifiers (i.e., species adsorbed onto Pd particle surface) have also been shown to enhance ethylene selectivity. Inorganic modifiers such as TiO change Pd ensemble size and modify ethylene adsorption strength whereas organic modifiers such as diphenylsulfide are thought to create a surface template effect which favours acetylene adsorption with respect to ethylene. A number of metals and synthetic approaches have been explored to prepare Pd bimetallic catalysts. Examples where enhanced selectivity is observed are generally associated with decreased Pd ensemble size and/or hindering of the ease with which an unselective hydride phase is formed for Pd. A final class of bimetallic catalysts are discussed where Pd is not thought to be the primary reaction site but merely acts as a site where hydrogen dissociation and spillover occurs onto a second metal (Cu or Au) where the reaction takes place more selectively.

关键词： acetylene     ethylene     selective hydrogenation     palladium     bimetallic    

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Preparation of polysulfone-based block copolymer ultrafiltration membranes by selective swelling and

《化学科学与工程前沿（英文）》 2022年 第16卷 第5期   页码 745-754 doi: 10.1007/s11705-021-2038-x

摘要： Selective swelling of block copolymers of polysulfone-b-poly(ethylene glycol) is an emerging strategy to prepare new types of polysulfone ultrafiltration membranes. Herein, we prepared nanoporous polysulfone-b-poly(ethylene glycol) ultrafiltration membranes by selective swelling and further promoted their porosity and ultrafiltration performances by using CaCO3 nanoparticles as the sacrificial nanofillers. Different contents of CaCO3 nanoparticles were doped into the solution of polysulfone-b-poly(ethylene glycol), and thus obtained suspensions were used to prepare both self-supported and bi-layered composite structures. Selective swelling was performed on the obtained block copolymer structures in the solvent pair of ethanol/acetone, producing nanoporous membranes with poly(ethylene glycol) lined along pore walls. The CaCO3 nanoparticles dispersed in polysulfone-b-poly(ethylene glycol) were subsequently etched away by hydrochloric acid and the spaces initially occupied by CaCO3 provided extra pores to the block copolymer layers. The porosity of the membranes was increased with increasing CaCO3 content up to 41%, but further increase in the CaCO3 content led to partial collapse of the membrane. The sacrificial CaCO3 particles provided extra pores and enhanced the connectivity between adjacent pores. Consequently, the membranes prepared under optimized conditions exhibited up to 80% increase in water permeance with slight decrease in rejection compared to neat membranes without the use of sacrificial CaCO3 particles.

关键词： block copolymers     selective swelling     ultrafiltration     CaCO3 nanoparticles     sacrificial nanofillers    

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Conversion of phenol to cyclohexane in the aqueous phase over Ni/zeolite bi-functional catalysts

Jimei Zhang, Fuping Tian, Junwen Chen, Yanchun Shi, Hongbin Cao, Pengge Ning, Shanshan Sun, Yongbing Xie

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 288-298 doi: 10.1007/s11705-020-1932-y

摘要： A series of Ni/HZSM-5 and Ni/HIM-5 bi-functional catalysts were synthesized and applied to the aqueous-phase hydrodeoxygenation (HDO) of phenol. The Ni dispersibility and particle sizes were shown to be directly related to the porosity and crystal sizes of the parent zeolites, which further influenced the catalytic performances. The large pores and small crystal sizes of the parent zeolites were beneficial for dispersing Ni and forming small Ni particles, and the corresponding Ni/zeolite catalyst exhibited a higher phenol conversion and selectivity towards hydrocarbons. Importantly, the Ni/HIM-5 bi-functional catalyst exhibited a high activity (98.3%) and high selectivity for hydrocarbons (98.8%) when heated at 220°C for 1 h and is thus a new potential catalyst for the HDO of phenolics to form hydrocarbons in the aqueous phase.

关键词： aqueous-phase hydrodeoxygenation     phenol     hydrocarbons     Ni/HIM-5     bi-functional catalyst    

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Highly efficient and selective removal of vanadium from tungstate solutions by microbubble floating-extraction

《化学科学与工程前沿（英文）》 2023年 第17卷 第5期   页码 581-593 doi: 10.1007/s11705-022-2235-2

摘要： Selective separation of dissolved tungsten and vanadium is of great significance for the utilization of the secondary resources of these elements. In this work, selective removal of vanadium from tungstate solutions via microbubble floating-extraction was systematically investigated. The results indicated that vanadium can be more easily mineralized over tungsten from tungstate solutions using methyl trioctyl ammonium chloride as mineralization reagent under weak alkaline conditions. Owing to the higher bubble and interface mass transfer rates, high-efficiency enrichment and deep separation of vanadium could be achieved easily. Additionally, the deep recovery of tungsten and vanadium from the floated organic phase could be easily realized using a mixed solution of sodium hydroxide and sodium chloride as stripping agents. The separation mechanism mainly included the formation of hydrophobic complexes, their attachment on the surface of rising bubbles, and their mass transfer at the oil–water interface. Under the optimal conditions, the removal efficiency of vanadium reached 98.5% with tungsten loss below 8% after two-stage microbubble floating-extraction. Therefore, the microbubble floating-extraction could be an efficient approach for separating selectively vanadium from tungstate solutions, exhibiting outstanding advantages of high separation efficiency and low consumption of organic solvents.

关键词： tungsten     vanadium     selective separation     reagent mineralization     microbubble floating-extraction    

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Mechanistic insights into the selective photocatalytic degradation of dyes over TiO/ZSM-11

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1701-5

摘要：

● TiO2/ZSM-11 was prepared by a facile solid state dispersion method.

关键词： Selective dye degradation     Photocatalysis     TiO2     ZSM-11     Chemisorption    

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标题 作者 时间 类型 操作

Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selectivecatalytic oxidation of cyclohexane

期刊论文

Studies on QSAR of metalloporphyrin catalysts in the oxidation of cyclohexane to adipic acid

CHEN Yixia, SHE Yuanbin, XU Jing, LI Yan

期刊论文

Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

期刊论文

Advances and perspectives in catalysts for liquid-phase oxidation of cyclohexane

Hui LI, Yuanbin SHE, Tao WANG

期刊论文

Transition metal-doped heteropoly catalysts for the selective oxidation of methacrolein to methacrylic

Yanxia Zheng,Heng Zhang,Lei Wang,Suojiang Zhang,Shaojun Wang

期刊论文

Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

期刊论文

β-Cyclodextrin promoted oxidation of primary amines to nitriles in water

Dongpo SHI, Hongbing JI, Zhong LI

期刊论文

Selective oxidation of o -nitrotoluene to o -nitrobenzaldehyde with metalloporphyrins as biomimetic catalysts

Xinling WANG, Yuanbin SHE,

期刊论文

Enhancing the aromatic selectivity of cyclohexane aromatization by CO2 coupling

期刊论文

Efficient base-free oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid over copper-doped

Feng Cheng, Dongwen Guo, Jinhua Lai, Meihui Long, Wenguang Zhao, Xianxiang Liu, Dulin Yin

期刊论文

Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

期刊论文

Preparation of polysulfone-based block copolymer ultrafiltration membranes by selective swelling and

期刊论文

Conversion of phenol to cyclohexane in the aqueous phase over Ni/zeolite bi-functional catalysts

Jimei Zhang, Fuping Tian, Junwen Chen, Yanchun Shi, Hongbin Cao, Pengge Ning, Shanshan Sun, Yongbing Xie

期刊论文

Highly efficient and selective removal of vanadium from tungstate solutions by microbubble floating-extraction

期刊论文

Mechanistic insights into the selective photocatalytic degradation of dyes over TiO/ZSM-11

期刊论文