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A highly efficient La-modified ZnAl-LDO catalyst and its performance in the synthesis of dimethyl carbonate from methyl carbamate and methanol

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Chinese Journal of Chemical Engineering 2023年第9期61卷 9-23页

作者： Mingxue Yin Bo Jia Kuiyi You Bo Jin Yangqiang Huang Xiao Luo Zhiwu Liang College of Chemistry and Chemical Engineering the Engineering Research Center of Advanced CatalysisMinistry of EducationHunan UniversityChangsha 410082China College of Chemical Engineering Xiangtan UniversityXiangtan 411105China

In this paper,the highly efficient ZnAlLa layered double oxide(ZnAlLa-LDO)catalyst was evaluated and used in methyl carbamate(MC)alcoholysis synthesis of dimethyl *** optimal conditions,the MC conversion was 33.5% and the dimethyl carbonate(DMC)selectivity was up to 92,4% at 443 K and in 9 *** prepared catalysts were well characterized to investigate the effect on the catalytic performance and reaction catalysis *** experimental results show that the addition of La adjusted the structure and chemical properties of ZnAl composite oxide and that the synergistic effect among Zn,Al and La play a key role in adjusting the acid-base properties and stability of the catalyst,which definitely improved the DMC selectivity and catalytic *** on the proposed reaction mechanism,two kinetic models of the catalytic reaction were established and modified:LangmuirHinshelwood and power-rate law kinetic *** good agreement between kinetic models and experimental data showed that the power-rate law kinetic model based on the elementary reactions is a suitable model for providing a theoretical *** pre-exponential factor and activation energy of the main reaction are 5.77×10^(7)and 77.60 kJ·mol^(-1),respectively.

关键词： Methanol Urea alcoholysis Dimethyl carbonate Kinetic model

Cavity-controlled methanol conversion over zeolite catalysts

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National Science Review 2023年第9期10卷 72-91页

作者： Wenna Zhang Shanfan Lin Yingxu Wei Peng Tian Mao Ye Zhongmin Liu National Engineering research center of Lower-Carbon catalysis Technology Dalian National Laboratory for Clean Energy iChEM(Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Energy College University of Chinese Academy of Sciences State Key Laboratory of catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

The successful development and application in industry of methanol-to-olefins(MTO) process brought about an innovative and efficient route for olefin production via non-petrochemical resources and also attracted attention of C1 chemistry and zeolite *** sieve catalysts with diversified microenvironments embedding unique channel/cavity structure and acid properties,exhibit demonstrable features and advantages in the shape-selective catalysis of ***,shape-selective catalysis over8-MR and cavity-type zeolites with acidic supercage environment and narrow pore opening manifested special host-guest interaction between the zeolite catalyst and guest reactants,intermediates and *** caused great differences in product distribution,catalyst deactivation and molecular diffusion,revealing the cavity-controlled methanol conversion over 8-MR and cavity-type zeolite ***,the dynamic and complicated cross-talk behaviors of catalyst material(coke)-reaction-diffusion over these types of zeolites determines the catalytic performance of the methanol *** this review,we shed light on the cavity-controlled principle in the MTO reaction including cavity-controlled active intermediates formation,cavity-controlled reaction routes with the involvement of these intermediates in the complex reaction network,cavity-controlled catalyst deactivation and cavity-controlled *** these were exhibited by the MTO reaction performances and product selectivity over 8-MR and cavity-type zeolite *** strategies inspired by the cavity-controlled principle were developed,providing great promise for the optimization and precise control of MTO process.

关键词： methanol-to-olefins cavity-controlled principle reaction intermediates and routes deactivation and diffusion shape-selective catalysis

Single atom catalysts by atomic diffusion strategy

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Nano research 2021年第12期14卷 4398-4416页

作者： Lihong Lin Zhuo Chen Wenxing Chen Energy&catalysis center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing100081China

The depletion of energy and increasing environmental pressure have become one of the main challenges in the world *** high-efficiency catalysts bring hope for efficient conversion of energy and effective treatment of pollutants,especially,single-atom catalysts(SACs)are promising ***,we comprehensively summarizes the atomic diffusion strategy,which is considered as an effective method to prepare a series of *** to the different diffusion forms of the precursors,we review the synthesis pathways of SACs from three aspects:gas diffusion,solid diffusion and liquid *** gaseous diffusion method mainly discusses atomic layer deposition(ALD)and chemical vapor deposition(CVD),both of which carry out gas phase mass transfer at high *** solid-state diffusion method can be divided into nanoparticle transformation into single atoms and solid atom *** diffusion mainly describes the electrochemical method and the molten salt *** hope this review can trigger the rational design of SACs.

关键词： single atomic catalyst gas diffusion solid diffusion liquid diffusion

Current gold Prospecting in China

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1298-1320页

作者： LEI Shibin QING Min NIU Cuiyi WANG Liang gold Mines Unit Ministry of Land and Resources Geological Institute of gold Ministry of Land and Resources

In China, there are 12 types of gold deposits in 57 class-Ill metallogenic zones, formed in 7 main metaUogenic periods. Most gold deposits are small or occur as ore spots; very large deposits are rare with relatively poor quality, mainly medium to low grade. Only 35% of the total gold reserves is identified, while a large amount of reserves is yet to be identified. In recent years, China Geological Survey has organized or conducted mineral resources survey and evaluation project, replacement resources prospecting for deposits in crisis, old mines prospecting and commercial prospecting funded or encouraged by the Central Government. These efforts have been fruitful. According to the temporal and spatial allocation of gold resources, and experiences from recent prospecting efforts, western China and the deep layers and peripheries of the-sits in eastern China have relatively high prospecting potential. The government should give even more support to the gold industry and strengthen technological innovation to help address difficulties in gold exploitation and processing. The government should also formulate consistent plans, consolidate mining rights, and promote integrated exploration, so as to achieve new major breakthroughs in gold prospecting. gold is both a form of material wealth and a way of storing wealth. It is a rare resource with dual functions of commodity and currency. As an important global strategic asset and a cornerstone of financial reserves, gold plays an irreplaceable role in securing national economic development, maintaining financial security, strengthening national comprehensive power and promoting RMB internationalization. Based on latest research and prospecting results, the thesis proposes preliminary conclusions on types, temporal and spatial allocation, and exploration and development of gold deposits in China; predicts China＇s gold resource potential; reviews recent gold prospecting and exploration efforts; and, in the hope of offering s

关键词： China gold resource metallogenic type current situation

Effective removal of the protective ligands from Au nanoclusters by ambient pressure nonthermal plasma treatment for CO oxidation

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Chinese Journal of catalysis 2018年第5期39卷 929-936页

作者： Yuan Tan Hua Liu Xiao Yan Liu Aiqin Wang Changjun Liu Tao Zhang State Key Laboratory of catalysis iChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Gold Catalysis Research CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Collaborative Innovation center of Chemical Science and Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

We used a dielectric barrier discharge(DBD)plasma technique to eliminate the protective ligand of ZnAl-hydrotalcite-supported gold *** used X-ray powder diffraction,ultraviolet-visible spectrophotometry,thermogravimetric analysis,and high angle annular dark-field-scanning transmission electron microscopy characterization to show that the samples pretreated with/without DBD-plasma displayed different performances in CO *** enhanced activity was obtained on the plasma-treated samples,implying that the protective ligand was effectively removed via the plasma *** crystal structure of the plasma-treated samples changed markedly,suggesting that the plasma treatment could not only break the chemical bond between the gold and the protective agent but could also decompose the interlayer ions over the hydrotalcite *** particle sizes of the gold after DBD-plasma treatment implied that it was a good way to control the size of the gold nanoparticles under mild conditions.

关键词： gold cluster Plasma Supported gold catalyst Protective ligand Carbon monoxide oxidation

Stereoselective electrochemical carboxylation ofα,β-unsaturated sulfones

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Chinese Chemical Letters 2023年第6期34卷 315-318页

作者： Zi-Xin Yang Liangchuan Lai Jingze Chen Hong Yan Ke-Yin Ye Fen-Er Chen Institute of Pharmaceutical Science and Technology College of ChemistryFuzhou UniversityFuzhou 350108China Department of Chemistry Engineering Center of Catalysis and Synthesis for Chiral MoleculesFudan UniversityShanghai 200433China Shanghai Engineering research center of Industrial Asymmetric catalysis of Chiral Drugs Fudan UniversityShanghai 200433China

As an attractive C1 synthon,carbon dioxide(CO_(2))has been extensively used in organic synthesis to produce carboxylic *** this research,stereoselective electrochemical carboxylation ofα,β-unsaturated sulfones has been developed under transition-metal-free *** the cinnamic acids and the derivatives are obtained selectively in the ***,arylpropiolates also can be produced from alkynyl sulfones.

关键词： Electrosynthesis Carbon dioxide Carboxylation α β-Unsaturated sulfone α β-Unsaturated carboxylic acid

Facile Growth of Porous Hierarchical Structure of ZnO Nanosheets on Alumina Particles via Heterogeneous Precipitation

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Journal of Materials Science & Technology 2013年第10期29卷 915-918页

作者： Hamid Tajizadegan Majid Jafari Mehdi Rashidzadeh Reza Ebrahimi-Kahrizsangi Omid Torabi Department of Materials Engineering Najafabad BranchIslamic Azad University catalysis & Nanotechnology research Division Research Institute of Petroleum Industry (RIPI)

ZnO nanosheets and nanoflakes were grown on alumina particles in the absence of surfactants via heterogeneous precipitation using urea, zinc acetate and bayerite as precursors. Thermo-gravimetric analysis （TGA）, X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FTIR） were used and the results indicated the formation of only two phases： wurtzite-type ZnO and γ-Al2O3. ZnO nanoflakes were grown on alumina particles in the samples with ZnO content of 40 and 60 wt%, By increasing the ZnO content to 80 wt%, a porous hierarchical structure of ZnO with nanosheet arrays appeared. Both of these nanoflakes and nanosheets were about 40-80 nm in thickness and about 1-2 μm in diameter. It was proposed that Zns（CO3）2（OH）6 nuclei undergo higher growth rates in thin sheets at edges of bayerite particles with a higher surface energy. The Brunauer-Emmett-Teller （BET） measurements proved a reachable high surface area for hierarchical structures of ZnO nanosheets, which could mainly be attributed to their unique growth on alumina particles. Also, UV absorption results revealed that ZnO--Al2O3 compositions still show the UV characteristic absorption of ZnO, which can evidence the presence of photocatalytic properties in ZnO-Al2O3 compositions.

关键词： ZnO Crystal growth Heterogeneous nucleation Hierarchical structures High surface area Morphology evolution

Porous FeO_x/BiVO_(4-δ)S_(0.08): Highly efcient photocatalysts for the degradation of Methylene Blue under visible-light illumination

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Journal of Environmental Sciences 2013年第10期25卷 2138-2149页

作者： Zhenxuan Zhao Hongxing Dai Jiguang Deng Yuxi Liu Yuan Wang Xinwei Li Guangmei Bai Baozu Gao Chak Tong Au Laboratory of catalysis Chemistry and Nanoscience Department of Chemistry and Chemical Engineering College of Environmental and Energy Engineering Beijing University of Technology Department of Chemistry and center for Surface Analysis and research Hong Kong Baptist University

Porous S-doped bismuth vanadate with an olive-like morphology and its supported iron oxide （y wt.% FeOx/BiVO4-δS0.08, y = 0.06, 0.76, and 1.40） photocatalysts were fabricated using the dodecylamine-assisted alcohol-hydrothermal and incipient wetness impregnation methods, respectively. It is shown that the y wt.% FeOx/BiVO4-δS0.08 photocatalysts contained a monoclinic scheetlite BiVO4 phase with a porous olive-like morphology, a surface area of 8.8-9.2 m^2/g, and a bandgap energy of 2.38-2.42 eV. There was co-presence of surface Bi^5＋, Bi^3＋, V^5＋, V^3＋, Fe^3＋, and Fe^2＋ species in y wt.% FeOx/BiVO4-δS0.08. The 1.40 wt.% FeOx/BiVO4-δS0.08 sample performed the best for Methylene Blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and FeOx co-doping, higher oxygen adspecies concentration, and lower baudgap energy were responsible for the excellent visible-light-driven catalytic activity of 1.40 wt.% FeOx/BiVO4-δS0.08.

关键词： sulfur-doped bismuth vanadate supported iron oxide visible-light-driven photocatalyst porous morphology Methylene Blue degradation

Housing Sulfur in Polymer Composite Frameworks for Li–S Batteries

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Nano-Micro Letters 2019年第1期11卷 282-325页

作者： Luke Hencz Hao Chen Han Yeu Ling Yazhou Wang Chao Lai Huijun Zhao Shanqing Zhang Centre for Clean Environment and Energy Environmental Futures Research Institute School of Environment and Science Griffith University Gold Coast Campus

Extensive efforts have been devoted to the design of micro-, nano-, and/or molecular structures of sulfur hosts to address the challenges of lithium–sulfur(Li–S) batteries, yet comparatively little research has been carried out on the binders in Li–S batteries. Herein, we systematically review the polymer composite frameworks that confine the sulfur within the sulfur electrode, taking the roles of sulfur hosts and functions of binders into consideration. In particular, we investigate the binding mechanism between the binder and sulfur host(such as mechanical interlocking and interfacial interactions), the chemical interactions between the polymer binder and sulfur(such as covalent bonding, electrostatic bonding, etc.), as well as the beneficial functions that polymer binders can impart on Li–S cathodes, such as conductive binders, electrolyte intake, adhesion strength etc. This work could provide a more comprehensive strategy in designing sulfur electrodes for long-life, large-capacity and high-rate Li–S battery.

关键词： Lithium–sulfur battery Sulfur cathode Binder Binding mechanism Polymer composite frameworks