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N-vinyl pyrrolidone promoted aqueous-phase dehydrogenation of formic acid over PVP-stabilized Ru nanoclusters

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Science China Chemistry 2016年第10期59卷 1342-1347页

作者： Hangyu liu Qingqing Mei Yanyan Wang huizhen liu Buxing Han Beijing National Laboratory for Molecular Sciences Key Laboratory of Colloid and Interface and Thermodynamics Institute of ChemistryChinese Academy of Sciences School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences

In this work, we fabricated the poly（N-vinyl-2-pyrrolidone）（PVP）-stabilized ruthenium（0） nanoclusters by reduction of RuC13 using different reducing agents, and studied their catalytic activity in hydrogen generation from the decomposition of formic acid. It was demonstrated that N-vinyl-2-pyrrolidone （NVP）, which is a monomer of PVP, could promote the reaction by coordination with Ru nanoparticles. The Ru nanoparticles catalyst reduced by sodium borohydride （NaBH4） exhibited highest catalytic activity for the decomposition of formic acid into H2 and CO2. The turnover of numenber （TOF） value could reach 26113 h-1 at 80 ℃. We believe that the effective catalysts have potential of application in hydrogen storage by formic acid.

关键词： carbon dioxide NVP ruthenium dehydrogenation of formic acid

Functional zirconium phosphate nanosheets enabled transfer hydrogenolysis of aromatic ether bonds over a low usage of Ru nanocatalysts

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Journal of Energy Chemistry 2023年第5期80卷 373-380,I0009页

作者： Jinliang Song Yayun Pang Chenglei Xiao huizhen liu Buxing Han School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006GuangdongChina Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high ***,we designed porous zirconium phosphate nanosheet-supported Ru nanocatalysts(Ru/ZrPsheet)as the heterogeneous catalyst by a process combining ball milling and molten-salt(KNO_(3)).Very interestingly,the fabricated Ru/ZrPsheetshowed good catalytic performance on the transfer hydrogenolysis of various types of aromatic ether bonds contained in lignin,i.e.,4-O-5,a-O-4,β-O-4,and aryl-O-CH3,over a low Ru usage(<0.5 mol%)without using any acidic/basic *** investigations indicated that the properties of Ru and the support were *** excellent activity of Ru/ZZrPsheetoriginated from the strong acidity and basicity of ZrPsheetand the higher electron density of metallic Ru0as well as the nanosheet structure of ZrPsheet.

关键词： Valorization of lignin Aromatic ether bonds Transfer hydrogenolysis synergistic cooperation Zirconium phosphate nanosheets

Selectively transform lignin into value-added chemicals

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Chinese Chemical Letters 2019年第1期30卷 15-24页

作者： Qingqing Mei Xiaojun Shen huizhen liu Buxing Han Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences

Lignin is one of the most important biomass resources. With the increasing consumption of petroleum resource, lignin transformation is of strategic significance and has attracted widely interest. As lignin is a random construction of aromatic monomers, the degradation products are usually very complex, which limits the scaling application of lignin as feedstock for valuable chemicals. Thus, it is desperately desired to develop highly selective approach to lignin conversion. This review first gives a brief introduction to the structure of lignin, and then summarized the methods for selective transformation of lignin into phenols, aldehydes, carboxylic acids, alkanes and arenes. Finally, the challenges and opportunities of lignin selective transformation are discussed.

关键词： Lignin Transformation Selective Value-added chemicals Biomass

Biomass Transformation

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Chemical Research in Chinese Universities 2024年第1期40卷 1-2页

作者： huizhen liu Qinglei Meng Buxing Han Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Center for Carbon Neutral Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China University of Chinese Academy of Sciences Beijing 100049 P. R. China

Biomass,as a renewable and abundant source of organic carbon,presents a sunstainable alternative to conventional fossil *** efficient conversion of biomass into fuels and chemicals is essential for alleviating energy and environmental issues and achieving carbon ***,the complexity and diversity of biomass feedstocks present significant research *** biomass types,lignocellulose holds particular promise due to its abundance,unique structure,and the fact that it is inedible and does not compete with the food supply.

关键词： Biomass Transformation holds

N-methylation of quinolines with CO2 and H2 catalyzed by Ru-triphos complexes

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Science China Chemistry 2017年第7期60卷 927-933页

作者： Zhenhong He huizhen liu Qingli Qian Lu Lu Weiwei Guo Lujun Zhang Buxing Han Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy oJSciences Beijing 100049China College of Chemistry and Chemical Engineering Shaanxi University of Science&TechnologyXi'an 710021China

N-methyl-tetrahydroquinolines(MTHQs) are a kind of very useful chemicals, which can be obtained from N-methylation of ***, the methylation of quinolines which is a kind of highly unsaturated nitrogen-containing heterocyclic aromatic compounds has not been reported. In this work, we report the first work for the synthesis of MTHQs by methylation of quinolines using CO_2 and H_2. It was found that Ru(acac)_3-triphos [triphos: 1,1,1-tris(diphenylphosphinomethyl)ethanl] complex was very active and selective for the N-methylation reaction of quinolines, and the yield of the desired product could reach 99%.

关键词： methylation hydrogenation quinoline derivatives carbon dioxide homogeneous catalysis

Recent advances in the coupling of CO2 and epoxides into cyclic carbonates under halogen-free condition

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Green Chemical Engineering 2020年第2期1卷 82-93页

作者： Feng Zhang Yanyan Wang Xiaochun Zhang Xiangping Zhang huizhen liu Buxing Han Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190PR China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing100049PR China State Key Laboratory of Multiphase Complex System Beijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing100190China

The chemical transformation of CO2 and epoxides into cyclic carbonates has been receiving much attention and is one of the successful examples for CO2 utilization as carbon *** catalysts containing halide anions have been explored and exhibit excellent catalytic ***,halogen salt is generally toxic and corrosive to *** a green chemistry perspective,it is more attractive to develop a halogen-free catalyst with excellent ***,a review of recent research progress of halogen-free catalysts in the cycloaddition of CO2 and epoxide is *** to previous experimental and theoretical works,two possible strategies for achieving the halogen-free process were *** relationship between catalytic activity and catalyst structure,the mechanism of CO2 activation should be both studied deeply combined with experimental results and DFT calculation,which can guide the design of new catalysts and realize halogen-free process under mild reaction conditions.

关键词： Cyclic carbonates Halogen-free catalysts Lewis acid-base Lewis acid-nucleophile Synergistic effect

Robust Carbon-Carbon Cleavage in Lignin to Produce Phenol and Cyclohexanone

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Chemical Research in Chinese Universities 2024年第1期40卷 29-35页

作者： WANG Lulin CHENG Xiaomeng DONG Minghua LUAN Sen WU Yuxuan HAN Buxing liu huizhen Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesCenter for Carbon Neutral ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

The challenge of breaking 5-5'bonds in lignin,attributed to their high bonding energy,has prompted the development of a new transformation ***,an important model compound for lignin,contains these 5-5'bonds,making it crucial to devise a strategy for their cleavage in lignin *** study introduces a novel method for transforming biphenyl,involving selective hydrogenation to cyclohexylbenzene by Ni/SiO2 catalyst,followed by its oxidation to phenol and cyclohexanone through a radical *** demonstrate that the catalysts with small particles have strong catalytic activity,while there is little difference in *** reason for the high selectivity of cyclohexylbenzene is due to the limited adsorption of cyclohexylbenzene on Ni/*** work presents a fresh approach to breaking resilient C-C bonds in lignin.

关键词： Lignin 5-5'Bond Ni/SiO_(2) Phenol

Ethylenediamine promoted the hydrogenative coupling of nitroarenes over Ni/C catalyst

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Chinese Chemical Letters 2019年第1期30卷 203-206页

作者： Youdi Yang Shaopeng Li Chao Xie Hangyu liu Yanyan Wang Qingqing Mei huizhen liu Buxing Han Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences

Azobenzene and its derivatives are key raw materials and it is an environmentally friendly method for the preparation of azobenzene by hydrogenative coupling of nitrobenzene. The development of nickel based catalyst for organic transformations is of importance because of its relatively low cost and toxicity. In this work, we found that ethylenediamine can enrich the electron state of Ni and make the azobenzene easily desorb from the surface of the catalyst, which inhibits the hydrogenation of azobenzene to aniline. The selectivity of azobenzene is greatly improved. When the ratio of Ni and ethylenediamine is 1:10, the yield of the azobenzene can reach 95.5%.

关键词： Selective hydrogenation Non-noble metal catalyst Electronic state Azobenzene Organic modifiers

Effect of Blasting Stress Wave on Dynamic Crack Propagation

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Computer Modeling in Engineering & Sciences 2024年第1期138卷 349-368页

作者： huizhen liu Duanying Wan Meng Wang Zheming Zhu Liyun Yang Key Laboratory for Old Bridge Detection&Reinforcement Technology of the Ministry of Transportation Beijing100088China School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing100083China MOE Key Laboratory of Deep Underground Science and Engineering School of Architecture and EnvironmentSichuan UniversityChengdu610065China

Stress waves affect the stress field at the crack tip and dominate the dynamic crack ***,evaluating the influence of blasting stress waves on the crack propagation behavior and the mechanical characteristics of crack propagation is of great significance for engineering *** this study,ANSYS/LS-DYNA was used for blasting numerical simulation,in which the propagation characteristics of blasting stress waves and stress field distribution at the crack tip were closely ***,ABAQUS was applied for simulating the crack propagation path and calculating dynamic stress intensity factors(DSIFs).The universal function was calculated by the *** results show that:the compressive wave causes the crack to close and the reflected tensile wave drives the crack to initiate and propagate,and failure mode is mainly tensile *** crack propagation velocity varies with time,which increases at first and then decreases,and the crack arrest occurs due to the attenuation of stress waves and dissipation of the blasting *** addition,crack arrest toughness is smaller than the crack initiation toughness,applied pressure waveforms(such as the peak pressure,duration,waveforms,wavelengths and loading rates)have a great influence on *** is conducive to our deep understanding or the study of blasting stress waves dominated fracture,suggesting a broad reference for the further development of rock blasting in engineering practice.

关键词： Crack propagation blasting stress wave dynamic stress intensity factor pressure waveform numerical simulation