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半旱地农业 3

农业节水 2

加氢 2

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Utilization of waste vanadium-bearing resources in the preparation of rare-earth vanadate catalysts for semi-hydrogenation

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1793-1806 doi: 10.1007/s11705-022-2191-x

摘要: Recycling industrial solid waste not only saves resources but also eliminates environmental concerns of toxic threats. Herein, we proposed a new strategy for the utilization of petrochemical-derived carbon black waste, a waste vanadium-bearing resource (V > 30000 ppm (10 −6)). Chemical leaching was employed to extract metallic vanadium from the waste and the leachate containing V was used as an alternative raw material for the fabrication of vanadate nanomaterials. Through the screening of various metal cations, it was found that the contaminated Na+ during the leaching process showed strong competitive coordination with the vanadium ions. However, by adding foreign Ce3+ and Y3+ cations, two rare-earth vanadates, viz., flower-like CeVO4 and spherical YVO4 nanomaterials, were successfully synthesized. Characterization techniques such as scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier-transform infrared, and N2 physisorption were applied to analyze the physicochemical properties of the waste-derived nanomaterials. Importantly, we found that rare-earth vanadate catalysts exhibited good activities toward the semi-hydrogenation of α,β-unsaturated aldehydes. The conversion of cinnamaldehyde and cinnamic alcohol selectivity were even higher than those of the common CeVO4 prepared using pure chemicals (67.2% vs. 27.7% and 88.4% vs. 53.5%). Our work provides a valuable new reference for preparing vanadate catalysts by the use of abundant vanadium-bearing waste resources.

关键词: petrochemical solid wastes     vanadium recovery     resource utilization     nanomaterials     semi-hydrogenation    

Corrigendum to ‘‘Structural and Kinetics Understanding of Support Effects in Pd-Catalyzed Semi-Hydrogenation Corrigendum

Yueqiang Cao, Xiaohu Ge, Yurou Li, Rui Si, Zhijun Sui, Jinghong Zhou, Xuezhi Duan, Xinggui Zhou

《工程(英文)》 2021年 第7卷 第5期   页码 701-701 doi: 10.1016/j.eng.2021.04.001

Pd催化乙炔半加氢反应载体效应的结构根源和动力学分析 Article

曹约强, 葛小虎, 李雨柔, 司锐, 隋志军, 周静红, 段学志, 周兴贵

《工程(英文)》 2021年 第7卷 第1期   页码 103-110 doi: 10.1016/j.eng.2020.06.023

摘要:

本文从催化剂微结构和动力学角度,认识和理解碳纳米管和α-Al2O3负载Pd催化乙炔半加氢反应的载体效应。动力学分析、XPS、H2-TPR、TPHD和原位XRD研究结果表明:与α-Al2O3相比,碳纳米管作为载体降低了催化剂Pd0 3d的电子结合能且抑制了氢化钯物种的形成,从而显著提高了目标产物乙烯的收率。进一步结合XAS、HRTEM、C2H4-TPD和DFT计算,发现碳纳米管负载的催化剂中Pd纳米颗粒次表面存在碳原子,这种独特的局域环境能显著弱化目标产物乙烯的吸附,有利于乙炔半加氢反应的发生。这些研究结果预示着调变Pd催化剂的局域环境和电子性质是一种构筑乙炔半加氢Pd催化剂的有效策略。

关键词: 乙炔半加氢     反应动力学     载体效应     电子效应     Pd局域环境    

The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

《化学科学与工程前沿(英文)》 2022年 第16卷 第3期   页码 397-407 doi: 10.1007/s11705-021-2076-4

摘要: The catalytic hydrogenation of carboxylic acid to alcohols is one of the important strategies for the conversion of biomass. Herein, a series of Ni-doped PtSn catalysts were prepared, characterized and studied in the hydrogenation of acetic acid. The Ni dopant has a strong interaction with Pt, which promotes the hydrogen adsorption, providing an activated hydrogen-rich environment for the hydrogenation. Meanwhile, the presence of Ni also improves the Pt dispersion, giving more accessible active sites for hydrogen activation. The cooperation of Pt and Ni significantly promotes the catalytic activity of the hydrogenation of acetic acid to ethanol. As a result, the catalyst with 0.1% Ni exhibits the best reaction activity, and its space time yield is twice as that of the PtSn/SiO2 catalyst. It provides a meaningful instruction on the catalyst design for the carboxylic acid hydrogenation.

关键词: acetic acid     ethanol     hydrogenation     Pt     Ni     cooperation effect    

Micromixing performance of the teethed high shear mixer under semi-batch operation

《化学科学与工程前沿(英文)》 2022年 第16卷 第4期   页码 546-559 doi: 10.1007/s11705-021-2069-3

摘要: Semi-batch operated reaction processes are necessary for some competitive reaction systems to achieve a desirable process selectivity and productivity of fine chemical products. Herein the structural and operating parameters of the teethed high shear mixers were adjusted to study the micromixing performance in the semi-batch operated system, using the Villermaux/Dushman reaction system. The results indicate that the rising of the rotor speed and the number of rotor teeth, the decrease of the width of the shear gap and the radial distance between the feed position and the inner wall of stator can enhance the micromixing level and lead to the decrease of the segregation index. Additionally, computational fluid dynamics calculations were carried out to disclose the evolution of the flow pattern and turbulent energy dissipation rate of the semi-batch operated high shear mixer. Furthermore, the correlation was established with a mean relative error of 8.05% and R2 of 0.955 to fit the segregation index and the parameters studied in this work, which can provide valuable guidance on the design and optimization of the semi-batch operated high shear mixers in practical applications.

关键词: high shear mixer     semi-batch operation     micromixing performance     Villermaux/Dushman system     segregation index    

NO hydrogenation to NH over FeCu/TiO catalyst with improved activity

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1973-1985 doi: 10.1007/s11705-023-2364-2

摘要: Ammonia is crucial in industry and agriculture, but its production is hindered by environmental concerns and energy-intensive processes. Hence, developing an efficient and environmentally friendly catalyst is imperative. In this study, we employed a straightforward and efficient impregnation technique to create various Cu-doped catalysts. Notably, the optimized 10Fe-8Cu/TiO2 catalyst exhibited exceptional catalytic performance in converting NO to NH3, achieving an NO conversion rate exceeding 80% and an NH3 selectivity exceeding 98% at atmospheric pressure and 350 °C. We employed in situ diffuse reflectance Fourier transform infrared spectroscopy and conducted density functional theory calculations to investigate the intermediates and subsequent adsorption. Our findings unequivocally demonstrate that Cu doping enhances the rate-limiting hydrogenation step and lowers the energy barrier for NH3 desorption, thereby resulting in improved NO conversion and enhanced selectivity toward ammonia. This study presents a pioneering approach toward energy-efficient ammonia synthesis and recycling of nitrogen sources.

关键词: NO hydrogenation     synthetic ammonia     10Fe-xCu/TiO2     high selectivity    

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    

HDS of dibenzothiophenes and hydrogenation of tetralin over a SiO

Qiang Wei, Jinwen Chen, Chaojie Song, Guangchun Li

《化学科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 336-348 doi: 10.1007/s11705-015-1535-1

摘要: A one-step synthesized Ni-Mo-S catalyst supported on SiO was prepared and used for hydrodesulphurization (HDS) of dibenzothiophene (DBT), and 4,6-dimethyl-dibenzothiophene (4,6-DMDBT), and for hydrogenation of tetralin. The catalyst showed relatively high HDS activity with complete conversion of DBT and 4,6-DMDBT at temperature of 280 °C and a constant pressure of 435 psi. The HDS conversions of DBT and 4,6-DMDBT increased with increasing temperature and pressure, and decreasing liquid hourly space velocity (LHSV). The HDS of DBT proceeded mostly through the direct desulphurization (DDS) pathway whereas that of 4,6-DMDBT occurred mainly through the hydrogenation-desulphurization (HYD) pathway. Although the catalyst showed up to 24% hydrogenation/dehydrogenation conversion of tetralin, it had low conversion and selectivity for ring opening and contraction due to the competitive adsorption of DBT and 4,6-DMDBT and insufficient acidic sites on the catalyst surface.

关键词: hydrodesulphurization (HDS)     hydrogenation     dibenzothiophene (DBT)     4     6-dimethyldibenzothiophene (4     6-DMDBT)     tetralin    

modification of Ni-Ti as efficient NiZnTi catalysts with both geometric and electronic improvements for hydrogenation

《化学科学与工程前沿(英文)》 2022年 第16卷 第4期   页码 461-474 doi: 10.1007/s11705-021-2072-8

摘要: The catalytic hydrogenation of nitroaromatics is an environmentally friendly technology for aniline production, and it is crucial to develop noble-metal-free catalysts that can achieve chemoselective hydrogenation of nitroaromatics under mild reaction conditions. In this work, zinc-modified Ni-Ti catalysts (NixZnyTi1) were fabricated and applied for the hydrogenation of nitroaromatics hydrogenation. It was found that the introduction of zinc effectively increases the surface Ni density, enhances the electronic effect, and improves the interaction between Ni and TiO2, resulting in smaller Ni particle size, more oxygen vacancies, higher dispersion and greater concentration of Ni on the catalyst surface. Furthermore, the electron-rich Niδ obtained by electron transfer from Zn and Ti to Ni effectively adsorbs and dissociates hydrogen. The results reveal that NixZnyTi1 (Ni0.5Zn0.5Ti1) shows excellent catalytic performance under mild conditions (70 °C and 6 bar). These findings provide a rational strategy for the development of highly active non-noble-metal hydrogenation catalysts.

关键词: bimetal strategy     oxygen vacancy     non-noble metal catalyst     hydrogenation     aromatic nitro compounds    

An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–Ce–Zr catalysts

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 950-962 doi: 10.1007/s11705-022-2162-2

摘要: A series of Cu–Ce–Zr catalysts with different Ce contents are applied to the hydrogenation of CO2 to CO/CH3OH products. The Cu–Ce–Zr catalyst with 2 wt% Ce loading shows higher CO selectivity (SCO = 0.0%–87.8%) from 200–300 °C, while the Cu–Ce–Zr catalyst with 8 wt% Ce loading presents higher CO2 conversion ( XCO2 = 5.4%–15.6%) and CH3OH selectivity ( SCH3OH = 97.8%–40.6%). The number of hydroxyl groups and solid solution nature play a significant role in changing the reaction pathway. The solid solution enhances the CO2 adsorption ability. At the CO2 adsorption step, a larger number of hydroxyl groups over the Cu–Ce–Zr catalyst with 8 wt% Ce loading leads to the production of H-containing adsorption species. At the CO2 hydrogenation step, a larger number of hydroxyl groups assists in encouraging the further hydrogenation of intermediate species to CH3OH and improving the hydrogenation rate. Hence, the Cu–Ce–Zr catalyst with 8 wt% Ce loading favors CH3OH selectivity and CO2 activation, while CO is preferred on the Cu–Ce–Zr catalyst with 2 wt% Ce loading, a smaller number of hydroxyl groups and a solid solution nature. Additionally, high-pressure in situ diffuse reflectance infrared Fourier transform spectroscopy shows that CO is produced from formate decomposition and that both monodentate formate and bidentate formate are active intermediate species of CO2 hydrogenation to CH3OH.

关键词: CO2 hydrogenation     Cu–Ce–Zr     hydroxyls     CO/CH3OH selectivity    

Bending and rotational behaviour of semi-continuous composite beams

WANG Jingfeng, LI Guoqiang

《结构与土木工程前沿(英文)》 2008年 第2卷 第2期   页码 116-122 doi: 10.1007/s11709-008-0015-9

摘要: Stresses and deflections were measured in various semi-continuous composite beams. The bending and rotational capacities of the composite connections were measured in terms of beam curvatures and deflections by using two full-scale semi-rigid composite frames with monotonic loadings. The effect of semi-rigid connections on the performance of composite beams with various loadings was compared with predictions and codes. The tests show that the semi-continuous composite beams are more economic and effective than the simple or continuous composite beams. The semi-rigid connections affect the bending capacities and beam deflections, so the connection behavior should be considered in the design of composite beams. Yielding analysis of the steel beam bottom flange has some influence on the deflection calculation of composite beams.

关键词: rotational     effective     deflection calculation     semi-continuous composite     full-scale semi-rigid    

Catalytic hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported

《化学科学与工程前沿(英文)》 2022年 第16卷 第10期   页码 1505-1513 doi: 10.1007/s11705-022-2164-0

摘要: Four supported catalysts, nickel and ruthenium on a HZSM-5 support, were prepared by equal volume impregnation and in-situ decomposition of carbonyl nickel. The properties of catalysts were investigated by catalytic hydro-conversion of 2,2′-dinaphthyl ether as the model compound and extraction residue of Naomaohu lignite as the sample under an initial H2 pressure of 5 MPa and temperature at 150 °C. According to the catalytic hydro-conversion results of the model compound, Ni−Ru/HZSM-5 exhibited the best catalytic performance. It not only activated H2 into H···H, but also further heterolytically split H···H into immobile H attached on the acidic centers of Ni−Ru/HZSM-5 and relatively mobile H+. Catalytic hydro-conversion of the extraction residue from Naomaohu lignite was further examined over the optimized catalyst, Ni−Ru/HZSM-5. Detailed molecular compositions of products from the extraction residue with and without hydrogenation were characterized by Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry. The analytical results showed that the oxygen-containing functional groups in products of hydrogenated extraction residue were obviously reduced after the catalytic treatment. The relative content of oxygenates in the product with catalytic treatment was 18.57% lower than that in the product without catalytic treatment.

关键词: HZSM-5     Ni-based catalyst     catalytic hydrogenation     coal     model compound    

Selective hydrogenation of acetylene over Pd/CeO

Kai Li, Tengteng Lyu, Junyi He, Ben W. L. Jang

《化学科学与工程前沿(英文)》 2020年 第14卷 第6期   页码 929-936 doi: 10.1007/s11705-019-1912-2

摘要: Five hundred ppm Pd/CeO catalyst was prepared and evaluated in selective hydrogenation of acetylene in large excess of ethylene since ceria has been recently found to be a reasonable stand-alone catalyst for this reaction. Pd/CeO catalyst could be activated by the feed gas during reactions and the catalyst without reduction showed much better ethylene selectivity than the reduced one in the high temperature range due to the formation of oxygen vacancies by reduction. Excellent ethylene selectivity of ~100% was obtained in the whole reaction temperature range of 50°C–200°C for samples calcined at temperatures of 600°C and 800°C. This could be ascribed to the formation of Pd Ce O or Pd-O-Ce surface species based on the X-ray diffraction and X-ray photoelectron spectroscopy results, indicating the strong interaction between palladium and ceria.

关键词: selective hydrogenation     acetylene     Pd/CeO2     strong interaction    

A comparison of the catalytic hydrogenation of 2-amylanthraquinone and 2-ethylanthraquinone over a Pd

Enxian Yuan, Xiangwei Ren, Li Wang, Wentao Zhao

《化学科学与工程前沿(英文)》 2017年 第11卷 第2期   页码 177-184 doi: 10.1007/s11705-016-1604-0

摘要: The hydrogenation of 2-ethylanthraquinone (eAQ), 2- -amylanthraquinone (taAQ) and their mixtures with molar ratios of 1:1 and 1:2 to the corresponding hydroquinones (eAQH and taAQH ) were studied over a Pd/Al O catalyst in a semi-batch slurry reactor at 60 °C and at 0.3 MPa. Compared to eAQ, TaAQ exhibited a significantly slower hydrogenation rate (about half) but had a higher maximum yield of H O and a smaller amount of degradation products. This can be ascribed to the longer and branched side chain in taAQ, which limits its accessibility to the Pd surface and its diffusion through the pores of the catalyst. Density functional theory calculations showed that it is more difficult for taAQ to adsorb onto a Pd (111) surface than for eAQ. The hydrogenation of the eAQ/taAQ mixtures had the slowest rates, lowest H O yields and the highest amounts of degradation products.

关键词: hydrogenation     hydrogen peroxide     anthraquinone     Pd catalyst     AO process    

Reconstruction of Cu–ZnO catalyst by organic acid and deactivation mechanism in liquid-phase hydrogenation

《化学科学与工程前沿(英文)》 2023年 第17卷 第9期   页码 1311-1319 doi: 10.1007/s11705-022-2281-9

摘要: A reconstructed Cu–ZnO catalyst with improved stability was fabricated by organic acid treatment method for the liquid-phase hydrogenation of dimethyl succinate to 1,4-butanediol. According to the characterization results of the fresh Cu–ZnO and reconstructed Cu–ZnO, three different forms of ZnO were suggested to be presented on the catalysts: ZnO having strong interaction with Cu species, ZnO that weakly interacted with Cu species and isolated ZnO. The first form of ZnO was believed to be beneficial to the formation of efficient active site Cu+, while the latter two forms of ZnO took the main responsibility for the deactivation of Cu–ZnO catalysts in the liquid-phase hydrogenation of diesters. The reconstruction of the Cu–ZnO catalyst by the organic acid treatment method resulted in a new Cu–ZnO catalyst with more Cu+ and less ZnO species that leads to deactivation. Furthermore, the deactivation mechanism of Cu–ZnO catalysts in liquid-phase diester hydrogenation in continuous flow system was proposed: the deposition of the polyesters on the catalysts via transesterification catalyzed by weakly interacted ZnO and isolated ZnO leads to the deactivation. These results provided meaningful instructions for designing highly efficient Cu–Zn catalysts for similar ester hydrogenation systems.

关键词: liquid phase     hydrogenation     Cu–ZnO     deactivation mechanism     1     4-butanediol     diester    

标题 作者 时间 类型 操作

Utilization of waste vanadium-bearing resources in the preparation of rare-earth vanadate catalysts for semi-hydrogenation

期刊论文

Corrigendum to ‘‘Structural and Kinetics Understanding of Support Effects in Pd-Catalyzed Semi-Hydrogenation

Yueqiang Cao, Xiaohu Ge, Yurou Li, Rui Si, Zhijun Sui, Jinghong Zhou, Xuezhi Duan, Xinggui Zhou

期刊论文

Pd催化乙炔半加氢反应载体效应的结构根源和动力学分析

曹约强, 葛小虎, 李雨柔, 司锐, 隋志军, 周静红, 段学志, 周兴贵

期刊论文

The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

期刊论文

Micromixing performance of the teethed high shear mixer under semi-batch operation

期刊论文

NO hydrogenation to NH over FeCu/TiO catalyst with improved activity

期刊论文

Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

期刊论文

HDS of dibenzothiophenes and hydrogenation of tetralin over a SiO

Qiang Wei, Jinwen Chen, Chaojie Song, Guangchun Li

期刊论文

modification of Ni-Ti as efficient NiZnTi catalysts with both geometric and electronic improvements for hydrogenation

期刊论文

An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–Ce–Zr catalysts

期刊论文

Bending and rotational behaviour of semi-continuous composite beams

WANG Jingfeng, LI Guoqiang

期刊论文

Catalytic hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported

期刊论文

Selective hydrogenation of acetylene over Pd/CeO

Kai Li, Tengteng Lyu, Junyi He, Ben W. L. Jang

期刊论文

A comparison of the catalytic hydrogenation of 2-amylanthraquinone and 2-ethylanthraquinone over a Pd

Enxian Yuan, Xiangwei Ren, Li Wang, Wentao Zhao

期刊论文

Reconstruction of Cu–ZnO catalyst by organic acid and deactivation mechanism in liquid-phase hydrogenation

期刊论文