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Liquid-phase esterification of methacrylic acid with methanol catalyzed by cation-exchange resin in a fixed bed reactor:Experimental and kinetic studies

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Chinese Journal of Chemical Engineering 2023年第6期58卷 1-10页

作者： Junyang Liu Luming Wang Yuhang Bian Chunshan Li Zengxi Li Jie Li School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Langfang Technological Center of Green Industry Langfang 065801China

The kinetic behavior of esterification between methacrylic acid and methanol catalyzed by NKC-9 resin was studied in a fixed bed *** reaction was conducted in the temperature range of 323.15 to 368.15 K with the molar ratio of reactants from 0.8 to 1.4 under certain *** measurement data were regression with the pseudo-homogeneous(P-H),Eley-Rideal(E-R),and Langmuir-Hinshelwood(L-H)heterogeneous kinetic *** adsorption experiments were implemented to gain the adsorption equilibrium constants of four *** the above three models,the L-H model exhibited the best fitting *** stability of NKC-9 was evaluated by long-term running with the yield of methyl methacrylate no decrease during 3000 h *** structure and physicochemical properties of the new and used catalyst were performed by several characterizations including thermogravimetric analysis(TG),scanning electron microscope(SEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FT-IR)and so on.

关键词： Kinetics Esterification Methyl methacrylate Cation-exchange resin Fix bed reactor

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Tuning the atomic configuration environment of MnN_(4) sites by Co cooperation for efficient oxygen reduction

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Journal of Energy Chemistry 2023年第7期82卷 547-559,I0012页

作者： Jing Wang Haihong Zhong Jun Yang Huiyu Li Pinggui Tang Yongjun Feng Dianqing Li State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyBeijing 100029China College of Science Hainan UniversityHaikou 570228HainanChina State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Carbon-based N-coordinated Mn(Mn-N_(x)/C)single-atom electrocatalysts are considered as one of the most desirable non-precious oxygen reduction reaction(ORR)candidates due to their insignificant Fenton reactivity,high abundance,and intriguing electrocatalytic ***,current MnN_(x)/C single-atom electrocatalysts suffer from high overpotentials because of their low intrinsic activity and unsatisfactory chemical ***,through an in-situ polymerization-assisted pyrolysis,the Co as a second metal is introduced into the Mn-N_(x)/C system to construct Co,Mn-N_(x)dual-metallic sites,which atomically disperse in N-doped 1D carbon nanorods,denoted as Co,Mn-N/CNR and *** electron microscopy and X-ray absorption spectroscopy(XAS)techniques,we verify the uniform dispersion of CoN4and MnN4atomic sites and confirm the effect of Co doping on the MnN_(4) electronic *** functional theory(DFT)calculations further elucidate that the energy barrier of ratedetermining step(^(*)OH desorption)decreases over the 2 N-bridged MnCoN_(6) moieties related to the pure MnN_(4).This work provides an effective strategy to modulate the local coordination environment and electronic structure of MnN_(4) active sites for improving their ORR activity and stability.

关键词： Dual-atom sites Oxygen reduction reaction M-Nx/C catalysts Coordination environment Electronic structure Synergistic effect

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Preparation and characterization of urea-formaldehyde resin]reactive kaolinite composites

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Particuology 2016年第1期14卷 203-209页

作者： Shiwei CheN Xuchen Lu Tizhuang Wang Zhimin Zhang State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China United Research Center for Resources and Materials Wuhai O16000 China

Novel urea-formaldehyde resin/reactive kaolinite composites containing 20-40wt%; kaolinite were prepared by in situ polymerization. The kaolinite was modified with tetraethoxysilane and a silane coupling agent to introduce reactive groups. Fourier-transform infrared spectroscopy and X-ray diffraction confirmed preparation of the urea-formaldehyde resin/reactive kaolinite composites. The composite morphology was investigated using scanning electron microscopy; the composites consisted of uni- form spherical particles. The surface chemical components of the composites were determined using energy-dispersive X-ray spectroscopy. The spectra showed that the reactive kaolinite was encapsulated by the urea-formaldehyde resin. The thermal properties of the composites were examined using dif- ferential scanning calorimetry and thermogravimetric analysis. The results showed that their thermal stability was much better than that of pure urea-formaldehyde resin, Reactive kaolinite addition greatly decreased formaldehyde emissions and improved the water resistance of the composites. A mechanism for urea-formaldehyde resin/reactive kaolinite composite synthesis is proposed.

关键词： Composites Reactive kaolinite Urea-formaldehyde resin Morphology Thermal property

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12-Tungstophosphoric acid niched in Zr-based metal-organic framework:a stable and efficient catalyst for Friedel-Crafts acylation

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Science China Chemistry 2018年第4期61卷 402-411页

作者： Latif Ullah Guoying Zhao Zichen Xu Hongyan He Muhammad Usman Suojiang Zhang Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Center of Excellence in Nanotechnology King Fahd University of Petroleum and MineralsDhahran 3126Saudi Arabia

Heteropoly acids(HPA) are well known for their versatile solid acid catalysis in diverse chemical reactions, however they suffer from low surface area(<10 m^2/g) and leaching into the reactions media, which reduce their prospects as industrial ***, a novel hybrid material HPW@Zr-BTC,composed of 12-tungstophoric acid(HPW) and Zr^(Ⅳ)-benzene tri-carboxylate(Zr-BTC) metal-organic framework(MOF), was prepared via one-pot solvothermal method. Excellent HPW loading up to 32.3 wt% was achieved, and HPW@Zr-BTC composite proved to be highly stable, besides the crystalline morphology of Zr-BTC was intact. The catalytic activity of the hybrid composite was explored via Friedel-Crafts acylation of anisole with benzoyl *** 28.2 wt% HPW@Zr-BTC showed excellent catalytic performance, with 99.4% anisole conversion and 97.6% yield(pmethoxybenzophenone) under solvent free conditions. Excellent retention of catalytic activity was achieved after at least five consecutive runs due to non-observable HPW leaching. The promising activity and stability of the catalyst forecasted its potential industrial applications.

关键词： dodeca-tungstophosphoric acid Zr-BTC metal-organic frameworks one-pot solvothermal synthesis heterogeneouscatalysis anisole acylation high temperature XRD

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Synthesis ofγ-MnS/nanoporous carbon/reduced graphene oxide composites for high-performance supercapacitor

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Carbon Resources Conversion 2022年第3期5卷 222-230页

作者： Abiola Ganiyat Olatoye Jie Zhang Qianyu Wang Erping Cao Wenli Li Emmanuel Oluwaseyi Fagbohun Yanbin Cui State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

In the present work,nanoporous carbon(NPC)was prepared from a metal-organic framework(zeolite imidazolate framework 8,ZIF-8).Different concentrations of graphene oxide(GO)were used to make NPC/reduced graphene oxide(NPC/rGO-x,x=0.5,1.0,1.5,and 2.0)composites,and thenγ-MnS/NPC/rGO-1 composite was synthesized via a simple hydrothermal *** electrochemical characteristics of porous carbon composites(NPC/rGO-x)andγ-MnS/NPC/rGO-1 electrodes were investigated by galvanostatic charge and discharge,cyclic voltammetry,and electrochemical impedance ***/rGO-1 showed the highest specific capacitance of 207 F/g at 0.5 A/***,theγ-MnS/NPC/rGO-1 electrode demonstrates exceptional electrochemical performance with a high specific capacitance of 300 F/g at 0.5 A/g and impressive cyclic stability of 70%capacitance retention after 10,000 cycles at 1 A/*** a result,this study demonstrates thatγ-MnS/NPC/rGO-1 electrode can be considered a promising candidate for high-performance supercapacitors.

关键词： Metal-organic framework Nanoporous carbon Reduced graphene oxide γ-MnS Supercapacitor

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Core-shell Ag-Pt nanoparticles:A versatile platform for the synthesis of heterogeneous nanostructures towards catalyzing electrochemical reactions

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Chinese Chemical Letters 2021年第11期32卷 3288-3297页

作者： Danye Liu Niuwa Yang Qing Zeng Hui Liu Dong Chen Penglei Cui Lin Xu Chaoquan Hu Jun Yang State Key Laboratory of Multiphase Complex Systems and Center of Mesoscience Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Nanjing IPE Institute of Green Manufacturing Industiy Nanjing 211100China School of Chemistry and Materials Science Jiangsu Key Laboratoiy of New Power BatteriesNanjing Normal UniversityNanjing 210023China

Heterogeneous nanostructures that are defined as a hybrid structure consisting of two or more nanoscale domains with distinct chemical compositions or physical characteristics have attracted intense efforts in recent *** this review,we focus on the introduction of a number of heterogeneous nanostructures derived using core-shell Ag-Pt nanoparticles as starting materials,including hollow,dimeric and composite structures and also highlight their application in catalyzing electrochemical reactions,e.g.,methanol oxidation reaction and oxygen reduction *** review not only shows the capability of core-shell Ag-Pt nanoparticles in producing various heterogeneous nanostructures as starting templates,but also highlights the structural design or electronic interaction that endows the heterogeneous nanostructures with enhanced catalytic properties either in methanol oxidation or in oxygen ***,we also make some perspectives for more heterogeneous nanostructures that may be prepared by using core-shell Ag-Pt particles or their derivatives so as to offer the readers the opportunities and challenges in this field.

关键词： Heterogeneous nanostructures Core-shell Electrochemical reaction Methanol oxidation reaction Oxygen reduction reaction

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Highly Purified Dicobalt Phosphide Nanodendrites on Exfoliated Graphene: in situ Synthesis and as Robust Bifunctional Electrocatalysts for Overall Water Splitting

Highly Purified Dicobalt Phosphide Nanodendrites on Exfoliat...

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中国化学会第十届全国无机化学学术会议

作者： Hui Liu Dong Chen Dan Ye Liu Hong Zhang Jun Yang State Key Laboratory of Multiphase Complex Systems and Center of Mesoscience Institute of Process Engineering Chinese Academy of Sciences

Designing highly active, earth-abundant and robust electrocatalysts with large surface areas and active sites, good electric conductivity, and minimization of gas bubble adhesion operated in the same electrolyte toward overall water splitting remains a potential challenge. Herein, we report an in situ synthesis of dendritic CoP nanostructures with high purity on exfoliated graphene（CoP/EG） showing superior performances toward both hydrogen evolution reaction（HER） and oxygen evolution reaction（OER）. The formation of CoP/CoO/Co（OH）x interfaces during electrocatalysis, abundant active sites featured by dendritic nanostructures, and fast electron transfer kinetics of EG as well as synergistic effects between active species and substrate would contribute to the improved catalytic performances for HER and OER. In specific, for the HER, the COP/EG shows excellent activity with a low overpotentials of 163 mV and 157 mV at 10 mA cm in 0.5 M HSO and 1.0 M KOH, respectively, while for the OER, it also exhibits high efficiency with an overpotential of 260 mV at 10 mA cm in 1.0 M KOH. Further, a CoP/EG||CoP/EG two-electrode alkaline electrolyzer affords a current density of 10 mA cm at a low cell voltage of 1.67 V, along with satisfied stability. An AA dry battery with a nominal voltage of 1.5 V can drive overall water splitting with obvious gas bubble release. Moreover, our synthetic approach might be applied for in situ synthesizing various metal phosphides/EG for electrolysis-based energy conversion.

关键词： Electrocatalyst Cobalt phosphide Hydrogen evolution reaction Oxygen evolution reaction Overall water splitting

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The manipulation of rectifying contact of Co and nitrogen-doped carbon hierarchical superstructures toward high-performance oxygen reduction reaction

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Carbon Energy 2024年第9期6卷 338-349页

作者： Jing Li Tingyu Lu Yu Fang Guangyao Zhou Mingyi Zhang Huan Pang Jun Yang Yawen Tang Lin Xu Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials ScienceJiangsu Collaborative Innovation Center of Biomedical Functional MaterialsNanjing Normal UniversityNanjingJiangsuChina College of Science Jinling Institute of TechnologyNanjingJiangsuChina Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbinHeilongjiangChina School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhouJiangsuChina State Key Laboratory of Multiphase Complex Systems Center of MesoscienceInstitute of Process EngineeringChinese Academy of SciencesBeijingChina

Rational design and construction of oxygen reduction reaction(ORR)electrocatalysts with high activity,good stability,and low price are essential for the practical applications of renewable energy conversion devices,such as metal-air *** modification through constructing metal/semiconductor Schottky heterointerface represents a powerful strategy to enhance the electrochemical ***,we demonstrate a concept of Schottky electrocatalyst composed of uniform Co nanoparticles in situ anchored on the carbon nanotubes aligned on the carbon nanosheets(denoted as Co@N-CNTs/NSs hereafter)toward *** experimental findings and theoretical simulation testify that the rectifying contact could impel the voluntary electron flow from Co to N-CNTs/NSs and create an internal electric field,thereby boosting the electron transfer rate and improving the intrinsic *** a consequence,the Co@N-CNTs/NSs deliver outstanding ORR activity,impressive long-term durability,excellent methanol tolerance,and good performance as the air-cathode in the Zn-air *** design concept of Schottky contact may provide the innovational inspirations for the synthesis of advanced catalysts in sustainable energy conversion fields.

关键词： Co-based electrocatalysts oxygen reduction reaction rectifying contact Zn-air batteries

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Effect of Reactive Nanoclays on Performances of PMMA/Reactive Nanoclay Nanocomposites

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Journal of Wuhan University of Technology(Materials Science) 2016年第6期31卷 1193-1200页

作者：陈世伟卢旭晨 WANG Tizhuang PAN Feng ZHANG Zhimin State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences (CAS) Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China United Research Center for Resource and Materials Wuhai 016000 China

PMMA/reactive nanoclay nanocomposites were prepared by emulsion polymerization using two different reactive nanoclays. X-ray diffraction（XRD） and thermogravimetric analysis（TGA） results confirmed that the reactive nanoclays, kaolinite and montmorillonite, were obtained by the silylation reaction and the double bonds were grafted onto the edges and surfaces of the nanoclays. The presence of reactive nanoclays could increase the average molecular weights, the glass transition temperatures（Tg） and improve the thermal properties of nanocomposite. The tensile properties, Young＇s modulus, and the aging properties of the nanocomposite films were also enhanced while the light transmittance decreased. Furthermore, the nanocomposites with the reactive kaolinite presented better performances than that with the reactive montmorillonite. Finally, the action mechanism of the reactive nanoclays to the performances of PMMA/reactive nanoclay nanocomposites was proposed.

关键词： nanoclay emulsion polymerization nanocomposite thermal property mechanical property

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Preparation and Characterization of Urea-formaldehyde Resin/reactive Montmorillonite Composites

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Journal of Wuhan University of Technology(Materials Science) 2017年第4期32卷 783-790页

作者：陈世伟卢旭晨 PAN Feng WANG Tizhuang ZHANG Zhimin .State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences (CAS) Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China . United Research Center for Resource and Materials Wuhai 016000 China

The urea-formaldehyde resin/reactive montmorillonite composites were prepared by in situ polymerization. The reactive montmorillonite was prepared firstly by being ion exchanged with organic molecules and secondly by being grafted with silane coupling agent, which could be demonstrated by X-ray diffraction（XRD） and thermogravimetric analysis（TGA）. Scanning electron microscopy（SEM） revealed that the morphology of the urea-formaldehyde resin/reactive montmorillonite composites were ellipsoid or columnar particles. Energy dispersive spectrometry（EDS） confirmed that the reactive montmorillonite was encapsulated by urea-formaldehyde resin. Differential scanning calorimetry（DSC） indicated that curing process of the ureaformaldehyde resin/reactive montmorillonite composites consumed more energy than pure urea-formaldehyde resin. Thermogravimetric analysis（TGA） showed that the thermal stability of the urea-formaldehyde resin/reactive montmorillonite composites improved compared to pure urea-formaldehyde resin. Furthermore, the reactive montmorillonites reduced the formaldehyde emission of the composites and increased the water resistance. Finally, the mechanism to prepare the urea-formaldehyde resin/reactive montmorillonite composites was proposed.

关键词： composite polycondensation X-ray morphology thermal property

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