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Catalytic process modeling and sensitivity analysis of alkylation of benzene with ethanol over MIL-101(Fe) and MIL-88(Fe)

Ehsan Rahmani, Mohammad Rahmani

《化学科学与工程前沿(英文)》 2020年 第14卷 第6期   页码 1100-1111 doi: 10.1007/s11705-019-1891-3

摘要: A solvothermal method was used to synthesize MIL-101(Fe) and MIL-88(Fe), which were used for alkylation of benzene. The synthesized catalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscope, dynamic light scattering, and BET techniques. Metal-organic frameworks (MOFs) were modeled to investigate the catalytic performance and existence of mass transfer limitations. Calculated effectiveness factors revealed absence of internal and external mass transfer. Sensitivity analysis revealed best operating conditions over MIL-101 at 120°C and 5 bar and over MIL-88 at 142°C and 9 bar.

关键词: MOFs     alkylation     ethylbenzene     catalysts pellet model     kinetic model     sensitivity analysis    

Preparation and microstructure analysis of Fe-doped PbTiO ceramic

QIANG Liangsheng, MA Jing, CHU Jia, ZHANG Xiaohong

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 140-144 doi: 10.1007/s11705-008-0021-4

摘要: Fe-doped PbTiO (PT) powder and bulk materials were prepared successfully by sol-gel technique and a subsequent sintering process using Fe (CH) as a dopant agent. The effects of pH and temperature on the Fe-doped PT system were investigated. Thermogravimetry/differential thermal analysis (TG/DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to analyze the composition and the microstructure of the PT ceramics. The results indicated that the thermal decomposition of xerogel included three stages: volatilization of adsorption water and organic composition, oxygenolysis of -butyl and acetate, and transformation of the crystalline phase. Well-stabilized collosol and gel could be obtained at 60°C and pH = 4.5. It was found that PbTiO, PbFeO, and TiO crystalline appeared in the Fe-doped PT system when the mass fraction of the dopant Fe was 0.03%. Furthermore, from STM analysis, it could be seen that the grain size of doped PT ceramics was homogeneous and about 1–2 ?m, and the pore of the PT ceramic was small. As a result, the PT ceramic had high tightness.

关键词: homogeneous     Thermogravimetry/differential thermal     tightness     oxygenolysis     sintering process    

Stability analysis of alkaline nitrobenzene-containing wastewater by a catalyzed Fe-Cu treatment process

FAN Jinhong, XU Wenying, GAO Tingyao, MA Luming

《环境科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 504-508 doi: 10.1007/s11783-007-0081-6

摘要: Iron and copper bimetallic system (catalyzed Fe-Cu process) is a promising technology for alkaline nitrobenzene-containing wastewater treatment. However, little is currently known about the changes of treatment efficiency with time

关键词: technology     bimetallic     catalyzed     nitrobenzene-containing wastewater     efficiency    

Coupled solid-fluid FE-analysis of an embankment dam

Michael PERTL, Matthias HOFMANN, Guenter HOFSTETTER

《结构与土木工程前沿(英文)》 2011年 第5卷 第1期   页码 53-62 doi: 10.1007/s11709-010-0084-4

摘要: A coupled solid-fluid FE-model for partially saturated soils, characterized by modeling the soil as a three-phase material consisting of a deformable soil skeleton and the fluid phases water and air, is reviewed briefly. As a constitutive model for the soil skeleton, the well-known Barcelona Basic model (BBM) is employed, which is formulated in terms of net stress and matric suction. For the BBM, a computationally efficient return mapping algorithm is proposed, which only requires the solution of a scalar nonlinear equation at the integration point level. The coupled FE-model is applied to the coupled transient numerical simulation of the water flow and the deformations and stresses in an embankment dam.

关键词: multi-phase model     unsaturated soil model     Barcelona Basic model (BBM)     return mapping algorithm     embankment dam    

The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1366-2

摘要:

•Bacterially-mediated coupled N and Fe processes examined in incubation experiments.

关键词: Denitrification     N2O emission     Fe(II) oxidation     Fe/N ratio     Fe minerals    

Implementation of an optimum algorithm for structural reliability analysis based on FEM

CHENG Ying, TU Hong-mao, FAN Hong-li

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 468-471 doi: 10.1007/s11465-006-0061-8

摘要: To analyze structural reliability by the stochastic FE (finite element) method rapidly and efficiently, a method combined with the FE method and gradient optimum algorithm based on ANSYS was presented when referring to the geometric interpretation of structural reliability index. ANSYS-based development was adopted to implement it. Results of an example demonstrate that the method requires fewer FE calculations compared with the design point method and Monte-Carlo simulation, and achieves satisfactory accuracy.

关键词: satisfactory     interpretation     algorithm     structural reliability     stochastic FE    

Cadmium removal mechanistic comparison of three Fe-based nanomaterials: Water-chemistry and roles ofFe dissolution

《环境科学与工程前沿(英文)》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1586-8

摘要:

● nZVI, S-nZVI, and nFeS were systematically compared for Cd(II) removal.

关键词: Nano zero valent iron     Sulfided zero valent iron     FeS     Cd(II) immobilization     Fe dissolution    

Synergistic effect of V and Fe in Ni/Fe/V ternary layered double hydroxides for efficient and durable

《化学科学与工程前沿(英文)》 2023年 第17卷 第1期   页码 102-115 doi: 10.1007/s11705-022-2179-6

摘要: High-performance and stable electrocatalysts are vital for the oxygen evolution reaction (OER). Herein, via a one-pot hydrothermal method, Ni/Fe/V ternary layered double hydroxides (NiFeV-LDH) derived from Ni foam are fabricated to work as highly active and durable electrocatalysts for OER. By changing the feeding ratio of Fe and V salts, the prepared ternary hydroxides were optimized. At an Fe:V ratio of 0.5:0.5, NiFeV-LDH exhibits outstanding OER activity superior to that of the binary hydroxides, requiring overpotentials of 269 and 274 mV at 50 mA·cm–2 in the linear sweep voltammetry and sampled current voltammetry measurements, respectively. Importantly, NiFeV-LDH shows extraordinary long-term stability (≥ 75 h) at an extremely high current density of 200 mA·cm–2. In contrast, the binary hydroxides present quick decay at 200 mA·cm–2 or even reduced current densities (150 and 100 mA·cm–2). The outstanding OER performance of NiFeV-LDH benefits from the synergistic effect of V and Fe while doping the third metal into bimetallic hydroxide layers: (a) Fe plays a crucial role as the active site; (b) electron-withdrawing V stabilizes the high valence state of Fe, thus accelerating the OER process; (c) V further offers great stabilization for the formed intermediate of FeOOH, thus achieving superior durability.

关键词: oxygen evolution reaction     electrocatalysts     ternary layered double hydroxides     long-term stability    

Floret-like Fe–N nanoparticle-embedded porous carbon superstructures from a Fe-covalent triazine polymer

《化学科学与工程前沿(英文)》 2023年 第17卷 第5期   页码 525-535 doi: 10.1007/s11705-022-2232-5

摘要: Fe–Nx nanoparticles-embedded porous carbons with a desirable superstructure have attracted immense attention as promising catalysts for electrochemical oxygen reduction reaction. Herein, we employed Fe-coordinated covalent triazine polymer for the fabrication of Fe–Nx nanoparticle-embedded porous carbon nanoflorets (Fe/N@CNFs) employing a hypersaline-confinement-conversion strategy. Presence of tailored N types within the covalent triazine polymer interwork in high proportions contributes to the generation of Fe/N coordination and subsequent Fe–Nx nanoparticles. Owing to the utilization of NaCl crystals, the resultant Fe/N@CNF-800 which was generated by pyrolysis at 800 °C showed nanoflower structure and large specific surface area, which remarkably suppressed the agglomeration of high catalytic active sites. As expect, the Fe/N@CNF-800 exhibited unexpected oxygen reduction reaction catalytic performance with an ultrahigh half-wave potential (0.89 V vs. reversible hydrogen electrode), a dominant 4e transfer approach and great cycle stability (> 92% after 100000 s). As a demonstration, the Fe/N-PCNF-800-assembled zinc–air battery delivered a high open circuit voltage of 1.51 V, a maximum peak power density of 164 mW·cm–2, as well as eminent rate performance, surpassing those of commercial Pt/C. This contribution offers a valuable avenue to exploit efficient metal nanoparticles-based carbon catalysts towards energy-related electrocatalytic reactions and beyond.

关键词: Fe–Nx nanoparticles     hypersaline-confinement conversion     floret-like carbon     covalent triazine polymers     oxygen reduction reaction    

Effect of Fe on NO release during char combustion in air and O

Ying GU, Xiaowei LIU, Bo ZHAO, Minghou XU

《能源前沿(英文)》 2012年 第6卷 第2期   页码 200-206 doi: 10.1007/s11708-012-0181-2

摘要: The chemistry of char was probed by studying nitrogen release under the reactions with air and oxy-fuel combustion. The experiments were conducted in a drop tube furnace and a fixed bed flow reactor. NO was observed during those experiments. The results show that the particle size of char generated at 1073 K in CO is larger than that in N . However, at 1573 K, it is smaller in CO atmosphere due to particle breaking by gasification of char and CO . The Fe addition increases the NO conversion ratio, and the effect of Fe rises steeply with the process going until it becomes stable in the end. The results also indicate that the release of NO increases more significantly with the Fe addition in oxy-fuel environment.

关键词: NO     Fe     char     combustion     CO2    

电沉积Zn-Fe-SiO2复合镀层研究

张英杰,范云鹰,董鹏,罗少林

《中国工程科学》 2008年 第10卷 第3期   页码 93-96

摘要:

报告了电沉积Zn-Fe-SiO2复合镀层的研究结果,论述了电流密度、极间距、搅拌方式、阳极数量及排布方式、添加剂等对Zn-Fe-SiO2复合镀层的影响及试验所取得的技术指标试验结果表明,Zn-Fe-SiO2复合镀层工艺具有过程稳定性好,维护措施简单方便,生产的环保及安全性好等优点。

关键词: 电沉积     复合镀层     Zn-Fe-SiO2    

Influence of Fe on electrocatalytic activity of iron-nitrogen-doped carbon materials toward oxygen reduction

Lin LI, Cehuang FU, Shuiyun SHEN, Fangling JIANG, Guanghua WEI, Junliang ZHANG

《能源前沿(英文)》 2022年 第16卷 第5期   页码 812-821 doi: 10.1007/s11708-020-0669-0

摘要: The development of highly active nitrogen-doped carbon-based transition metal (M-N-C) compounds for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs) greatly helps reduce fuel cell cost, thus rapidly promoting their commercial applications. Among different M-N-C electrocatalysts, the series of Fe-N-C materials are highly favored because of their high ORR activity. However, there remains a debate on the effect of Fe, and rare investigations focus on the influence of Fe addition in the second heat treatment usually performed after acid leaching in the catalyst synthesis. It is thus very critical to explore the influences of Fe on the ORR electrocatalytic activity, which will, in turn, guide the design of Fe-N-C materials with enhanced performance. Herein, a series of Fe-N-C electrocatalysts are synthesize and the influence of Fe on the ORR activity are speculated both experimentally and theoretically. It is deduced that the active site lies in the structure of Fe-N , accompanied with the addition of appropriate Fe, and the number of active sites increases without the occurrence of agglomeration particles. Moreover, it is speculated that Fe plays an important role in stabilizing N as well as constituting active sites in the second pyrolyzing process.

关键词: oxygen reduction reaction     Fe-N-C     active sites     Fe addition     second heat treatment    

Fabrication of recyclable Fe chelated aminated polypropylene fiber for efficient clean-up of phosphate

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 840-852 doi: 10.1007/s11705-022-2253-0

摘要: Herein, a Fe3+-loaded aminated polypropylene fiber has been reported as an efficient phosphate adsorbent. The remarkable phosphate removal ability of the fiber is due to Fe3+ immobilization, and it demonstrates a maximum adsorption capacity of 33.94 mg·P·g–1. Adsorption experiments showed that the fiber is applicable over a wide pH range from 2 to 9. Furthermore, the adsorption kinetics and isotherm data were consistent with the pseudo-second-order and Langmuir adsorption models, respectively. The adsorption equilibrium of the fiber for phosphate was reached within 60 min, indicating an efficient monolayer chemisorption process. Moreover, the adsorbent maintained prominent phosphate removal in the presence of competitive ions such as NO3 and Cl, exhibiting high selectivity. More importantly, the fiber demonstrated excellent reusability (5 times) and low adsorption limit below 0.02 mg·P·g–1. In addition, the phosphate removal efficiency of the fiber can exceed 99% under continuous flow conditions. The adsorption mechanism was studied by X-ray photoelectron spectroscopy, showing that the adsorption of phosphate on the fiber mainly depended on the chemical adsorption of the modified Fe3+. Overall, this study proves that the fiber possesses many advantages for phosphate removal, including high adsorption efficiency, lower treatment limit, good recyclability, and environmental friendliness.

关键词: phosphate adsorption     aminated polypropylene fiber     Fe3+     ligand exchange     reusability    

Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 251-255 doi: 10.1007/s11705-007-0045-1

摘要: A heterogeneous chiral catalyst Fe(III)-CS (chitosan) complex/mesoporous molecular sieve SBA-15 (Santa Barbara Amorphous) was prepared. The asymmetric transfer hydrogenations of prochiral acetophenone and 4-methyl-2-pentanone to corresponding chiral alcohols were carried out on Fe-CS/SBA-15 at atmosphere pressure using 2-propanol as hydrogen donor. Effects of Fe content in catalyst, reaction temperature, reaction time and promoter KOH concentration on the conversion of substrates and enantioselectivity were investigated. Fe-CS/SBA-15 with 2.2% mass fraction Fe exhibits considerable enantioselectivity and catalytic activity for the asymmetric transfer hydrogenations of aromatic ketone and aliphatic ketone. Under optimal reaction conditions: KOH concentration 0.03 mol/L, reaction temperature 70ºC and reaction time 4 h, enantiomer excess (ee) of ()-1-phenylethanol and conversion of acetophenone can reach 87.4% and 27.7%, respectively. Under the above KOH concentration and reaction temperature and reaction time of 8 h, the ee of ()-4-methyl-2-pentanol and conversion 4-methyl-2-pentanone amounted to 50.2% and 25.5%, respectively.

关键词: asymmetric transfer     enantioselectivity     Fe-CS/SBA-15     aliphatic     aromatic    

Controllable Fe/HCS catalysts in the Fischer-Tropsch synthesis: Effects of crystallization time

Yifei Wang, Shouying Huang, Xinsheng Teng, Hongyu Wang, Jian Wang, Qiao Zhao, Yue Wang, Xinbin Ma

《化学科学与工程前沿(英文)》 2020年 第14卷 第5期   页码 802-812 doi: 10.1007/s11705-019-1866-4

摘要: The Fischer–Tropsch synthesis (FTS) continues to be an attractive alternative for producing a broad range of fuels and chemicals through the conversion of syngas (H and CO), which can be derived from various sources, such as coal, natural gas, and biomass. Among iron carbides, Fe C, as an active phase, has barely been studied due to its thermodynamic instability. Here, we fabricated a series of Fe C embedded in hollow carbon sphere (HCS) catalysts. By varying the crystallization time, the shell thickness of the HCS was manipulated, which significantly influenced the catalytic performance in the FTS. To investigate the relationship between the geometric structure of the HCS and the physic-chemical properties of Fe species, transmission electron microscopy, X-ray diffraction, N physical adsorption, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction, Raman spectroscopy, and Mössbauer spectroscopy techniques were employed to characterize the catalysts before and after the reaction. Evidently, a suitable thickness of the carbon layer was beneficial for enhancing the catalytic activity in the FTS due to its high porosity, appropriate electronic environment, and relatively high Fe C content.

关键词: Fischer–Tropsch synthesis     Fe-based catalyst     Fe2C     hollow carbon sphere     crystallization time    

标题 作者 时间 类型 操作

Catalytic process modeling and sensitivity analysis of alkylation of benzene with ethanol over MIL-101(Fe) and MIL-88(Fe)

Ehsan Rahmani, Mohammad Rahmani

期刊论文

Preparation and microstructure analysis of Fe-doped PbTiO ceramic

QIANG Liangsheng, MA Jing, CHU Jia, ZHANG Xiaohong

期刊论文

Stability analysis of alkaline nitrobenzene-containing wastewater by a catalyzed Fe-Cu treatment process

FAN Jinhong, XU Wenying, GAO Tingyao, MA Luming

期刊论文

Coupled solid-fluid FE-analysis of an embankment dam

Michael PERTL, Matthias HOFMANN, Guenter HOFSTETTER

期刊论文

The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The

期刊论文

Implementation of an optimum algorithm for structural reliability analysis based on FEM

CHENG Ying, TU Hong-mao, FAN Hong-li

期刊论文

Cadmium removal mechanistic comparison of three Fe-based nanomaterials: Water-chemistry and roles ofFe dissolution

期刊论文

Synergistic effect of V and Fe in Ni/Fe/V ternary layered double hydroxides for efficient and durable

期刊论文

Floret-like Fe–N nanoparticle-embedded porous carbon superstructures from a Fe-covalent triazine polymer

期刊论文

Effect of Fe on NO release during char combustion in air and O

Ying GU, Xiaowei LIU, Bo ZHAO, Minghou XU

期刊论文

电沉积Zn-Fe-SiO2复合镀层研究

张英杰,范云鹰,董鹏,罗少林

期刊论文

Influence of Fe on electrocatalytic activity of iron-nitrogen-doped carbon materials toward oxygen reduction

Lin LI, Cehuang FU, Shuiyun SHEN, Fangling JIANG, Guanghua WEI, Junliang ZHANG

期刊论文

Fabrication of recyclable Fe chelated aminated polypropylene fiber for efficient clean-up of phosphate

期刊论文

Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

期刊论文

Controllable Fe/HCS catalysts in the Fischer-Tropsch synthesis: Effects of crystallization time

Yifei Wang, Shouying Huang, Xinsheng Teng, Hongyu Wang, Jian Wang, Qiao Zhao, Yue Wang, Xinbin Ma

期刊论文