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Chemical Research in Chinese Universities 2024年第1期40卷 36-46页

作者： YANG Yinze ZHANG Liyan ZHOU Leilei CHENG Haiyang ZHAO Fengyu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of Applied Chemistry and Engineering University of Science Technology of ChinaHefei 230026P.R.China Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

The reductive amination of furfural to furfurylamine is an important and still challenging topic in the field of biomass conversion. In this work, we prepared a series of Ni/Al_(2)O_(3)-LaO_(x) catalysts by co-precipitation method, the role of La played in promoting the catalytic performances of reductive amination furfural was discussed based on the changes in the electronic state of Ni species, acidity, and Ni particle size. The catalytic activity and the selectivity of furfurylamine are highly dependent on the surface properties and the structure of the catalyst. The addition of La promoted the amount of strong acidic sites and the H2dissociation and spillover on the surface, thus inducing the improvement of the catalytic activity and furfurylamine selectivity. The Ni/Al_(2)O_(3)-0.5LaO_(x)catalyst with suitable acid sites gave a high yield of furfurylamine (94.9%) under mild reaction conditions. Moreover, the catalyst could be recycled five times without significant loss in activity. The Ni/Al_(2)O_(3)-LaO_(x) catalyst is of great promise in the production of amines via reductive amination reaction.

关键词： Reductive amination Furfural nickel catalyst Furfurylamine Lanthanum

Trinuclear nickel catalyst for Water Oxidation:Intramolecular Proton-Coupled Electron Transfer Triggered Trimetallic Cooperative O-O Bond Formation

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CCS Chemistry 2023年第1期5卷 245-256页

作者： Qi-Fa Chen Yao Xiao Rong-Zhen Liao Ming-Tian Zhang Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084 Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074

We report a molecular trinuclear nickel(TNC-Ni)catalyst for water oxidation that exhibited high catalytic performance and stability under neutral conditions(pH 7).Electrochemical studies disclosed that cooperation among the three nickel sites plays a vital role in both charge accumulation and O-O bond formation.This TNC-Ni catalyst could accomplish 4e−oxidation of water by involving all three nickel sites and the O-O bond formation was triggered by a charge distribution process from 5 to 5_(dp) via proton-coupled electron transfer.

关键词： water oxidation proton-coupled electron transfer nickel catalyst artificial photosynthesis O-O bond formation

Influence of Backbone and Axial Substituent of catalyst onα-Imino-ketone nickel Mediated Ethylene(Co)Polymerization

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Chinese Journal of Polymer Science 2022年第5期40卷 469-477页

作者： Yu-Kai Chu Xiao-Qiang Hu Yue Zhang Da-Jun Liu Yi-Xin Zhang Zhong-Bao Jian College of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 730022China

Theα-imino-ketone nickel catalyst is an emerging versatile platform that is easy to prepare and allows for the production of branched high molecular weight functionalized polyethylenes.However,study on this catalyst system is rare thus far.In this contribution,by introducing different backbones,flexible and rigid axial substituents into theα-imino-ketone framework,a family of cationic nickel catalysts were synthesized and fully characterized.Without the addition of any activator,systematic studies on ethylene polymerization and copolymerization with polar monomers were performed to explore the influence of both backbone and axial substituent on catalytic activity,polymer molecular weight,branching density and incorporation.In particular,owing to the unique semi-opening feature of theα-imino-ketone framework,the preferred nickel catalyst exhibited high activity of 175 kg·mol^(-1)·h^(-1)to produce functionalized polyethylene with molecular weight of 13.4 kg·mol^(-1)and comonomer incorporation of 2.9 mol%.

关键词： Olefin polymerization α-Imino-ketone ligand nickel catalyst Polar monomer

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Catalytic performance of cement clinker supported nickel catalyst in glycerol dry reforming

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Journal of Energy Chemistry 2014年第5期23卷 645-656页

作者： Hua Chyn Lee Kah Weng Siew Maksudur R.Khan Sim Yee Chin Jolius Gimbun Chin Kui Cheng Faculty of Chemical & Natural Resources Engineering Universiti Malaysia Pahang Lebuhraya Tun Razak 26300 Gambang Kuantan Pahang Malaysia Centre of Excellence for Advanced Research in Fluid Flow Universiti Malaysia Pahang Lebuhraya Tun Razak 26300 Gambang Kuantan Pahang Malaysia

The paper reports the development of cement clinker-supported nickel （with metal loadings of 5 wt%, 10 wt%, 15 wt% and 20 wt%） catalysts for glycerol dry （CO2） reforming reaction. XRF results showed that CaO constituted 62.0% of cement clinker. The physicochemical characterization of the catalysts revealed 32-folds increment of BET surface area （SBET） with the addition of nickel metal into the cement clinker, which was also corroborated by FESEM images. Significantly, XRD results suggested different types of Ni oxides formation with Ni loading, whilst Ca3SiO5 and Ca2Al0.67Mn0.33FeO5 were the main crystallite species for pure cement clinker. Temperature-programmed reduction analysis yielded three domains of H2 reduction peaks, viz. centered at approximately 750 K referred to as type-Ⅰ peaks, another peaks at 820 K denoted as type-Ⅱ peaks and the highest reduction peaks, type-Ⅲ recorded at above 1000 K. 20 wt% Ni was found to be the best loading with the highest XG and H2 yield, whilst the lowest methanation activity. Syngas with lower H2/CO ratios （0.6 to 1.5） were readily produced from glycerol dry reforming at CO2-to-Glycerol feed ratio （CGR） of unity. Nonetheless, carbon deposit comprised of whisker type （Cv） and graphitic-like type （Cc） species were found to be in majority on 20 wt%Ni/CC catalysts.

关键词： cement clinker dry reforming glycerol nickel catalyst syngas

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SYNTHESIS OF cis-1, 4-POLYBUTADIENE WITH nickel catalyst INVESTIGATIONS ON INTERACTIONS BETWEEN THE CATALYTIC COMPONENTS BY USING UV-VIS SPECTRUM

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Chinese Journal of Polymer Science 1987年第1期5卷 45-52页

作者：陈滇宝许光唐学明 Qingdao College of Chemical Technology Qingdao

Ni（Ⅱ） naphthenate in hydrogenated gasoline or toluene will appear light green, which is the result of absorption in the red and blue bands of the spectrum. The three peaks caused by the spin-allowed d-d transitions are 403, 680, and 1170nm respectively, and are similar to those of Ni（H2O）6+2. The configuration of Ni（Ⅱ） complex is octabedral.In a two-component system of Ni（naph）2-Al（i-Bu）3, the naphthenate ligand attached to Ni（Ⅱ） can be exchanged for the alkyl group on tri-isobutylaluminium, if Al（i-Bu）3/Ni（naph）2 in a system. containing metalalkyl and naphthenate does not exceed the value of 0.53. At a higher ratio, Al（i-Bu）3/Ni（naph）2>0.53, Ni（Ⅱ） is reduced to Ni（Ⅰ） and Ni（O）.In a two-component system Ni（naph）2-BF3·OEt2, a part of the naphthenate can be exchanged for halogen. A new Ni（Ⅱ） complex is formed, which consists of three new d-d bands in the region 360-1660 nm.

关键词： cis-1, 4-polybutadiene nickel catalyst Ziegler-Natta catalyst UV-VIS spectrum

Selective Hydrogenation of Maleic Anhydride to Succinic Anhydride over nickel catalyst Supported on Carbon Microspheres

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China Petroleum Processing & Petrochemical Technology 2021年第4期23卷 75-82页

作者： Zhou Yafen Chen Qilin Wang Qing Song Yu Zhou Limei Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province China West Normal UniversityNanchong 637002

The colloidal carbon microspheres(CMS)were prepared by the hydrothermal method.The nickel catalysts supported on carbon microspheres(Ni/CMS)were further prepared and were characterized by the Fourier transform infrared spectroscopy(FTIR),the X-ray diffraction(XRD),the scanning electron microscopy(SEM),the transmission electron microscopy(TEM),and the N_(2)adsorption technique.The selective hydrogenation of maleic anhydride(MA)to succinic anhydride(SA)over the Ni/CMS catalysts was investigated.The results indicated that the Ni/CMS catalyst,which was prepared with glucose as carbon source and calcined at 500℃,exhibited the best performance.The hydrogen pressure,reaction temperature,and reaction time could significantly affect the conversion of maleic anhydride during the hydrogenation reaction.A 98.4%conversion of MA and an 100%selectivity to SA were achieved over the Ni/CMS catalyst in acetic anhydride solvent under mild conditions covering a temperature of 90℃,a H2 pressure of 1.0 MPa,and a reaction time of 3 h.

关键词： carbon microsphere nickel catalyst hydrogenation maleic anhydride succinic anhydride

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Photoresponsive α-Diimine nickel Modulated Ethylene (Co)Polymerization

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Chinese Journal of Chemistry 2022年第24期40卷 2919-2926页

作者： Jingshuang Yang Xiaoqiang Hu Zhongbao Jian State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesRenmin Street 5625ChangchunJilin130022 China University of Science and Technology of China HefeiAnhui230026 China

Beyond the single ligand electronic and/or steric modifications, external stimuli are a useful tool for modulating catalytic polymerization reactions. Light stands out from external stimuli, but the corresponding photoresponsive transition metal catalysts are significantly rare for olefin polymerization due to the difficult synthesis. In this contribution, in consideration of the key role of steric shielding on the axial sites, we installed four concerted azobenzene moieties into symmetrically terphenyl-based α-diimine Ni(II) complexes to prepare photoresponsive catalysts, which were applied to ethylene polymerization and copolymerization with polar monomer. Via the trans-cis isomerization of azobenzene-functionalized Ni(II) catalysts in dark or under UV light, catalytic activity, polymer molecular weight, branching density, incorporation of co-monomer, and even the ratio of branching pattern were significantly modulated in ethylene (co)polymerizations. This photo-controlled strategy behaved an opposite influence between ethylene polymerization and copolymerization, in terms of catalytic activity and polymer molecular weight. As a result, slightly branched ultrahigh molecular weight polyethylenes and high molecular weight functionalized polyethylenes were produced at ambient conditions.

关键词： Olefin polymerization Photochemistry Polyethylene Polar monomer nickel catalyst

Macrocyclic Binuclearα-Diimine nickel catalysts for Ethylene Polymerization

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Chemical Research in Chinese Universities 2023年第5期39卷 797-802页

作者： YANG Jingshuang ZHANG Yuxing JIAN Zhongbao State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026P.R.China

Polyolefins are globally important plastics.Molecular weight and molecular weight distribution are two key parameters for determining the properties of polyolefin materials.In this contribution,we develop a strategy for combining the macrocyclic framework and the binuclear effect into the benchmarkα-diimine late transition metal catalysts,and thus macrocyclic binuclearα-diimine nickel catalysts(Ni_(2)-Me and Ni_(2)-iPr)are prepared.Compared to the classical Brookhart's acyclic mononuclearα-diimine nickel analogues(Ni_(1)-Me and Ni_(1)-iPr),these nickel catalysts exhibit enhanced thermostability(up to 110℃)and produce polyethylenes with higher molecular weights(up to 7 times)and lower branching densities(as low as 9 branches/1000C)in methylaluminoxane(MAO)activated ethylene polymerization.This translates into the ability of the catalyst to afford more linear high molecular weight polyethylenes.In particular,bimodal polyethylenes with broad molecular weight distributions(Mw/Mn=8.08-14.66)are generated by the sole catalyst.This work affords diverse polyethylenes.

关键词： Polyolefin nickel catalyst Diimine ligand Macrocyclic binuclear strategy Bimodal polyethylene

Selective hydroconversion of 5-hydroxymethylfurfural to 2,5-bis(hydroxymethyl)furan using carbon nanotubes-supported nickel catalysts

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Carbon Resources Conversion 2022年第4期5卷 289-298页

作者： Zexing Huang Xiaoao Sun Wenguang Zhao Xiaoting Zhu Zhijuan Zeng Qiong Xu Xianxiang Liu National&Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources Hunan Normal UniversityChangsha 410081PR China

2,5-Bis(hydroxymethyl)furan(BHMF)is a high-value,bio-based,rigid diol that resembles aromatic monomers for the production of different polyesters.In this work,a carbon nanotubes(CNTs)-supported nickel catalyst(Ni/CNTs)was prepared and used for the selective hydrogenation of 5-hydroxymethylfurfural(HMF)to BHMF at low hydrogen pressure.The prepared catalyst was analyzed by nitrogen adsorption-desorption isotherms,X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).According to kinetic studies,the rate constant for BHMF formation is significantly larger than that for the formation of the byproduct,5-methyl furfural(MF).At optimal reaction conditions,conversion and selectivity rates of HMF and BHMF were 99.8%and 95.0%,respectively.The mechanistic study indicated the coexistence of Ni0 and Ni2+species on the catalyst surface affects the catalytic performance.A possible mechanism was proposed to describe the synergetic effects of Ni0 and Ni2+.Furthermore,the catalyst can be easily separated from the reaction mixture for recycling.

关键词： Biomass transformation 5-Hydroxymethylfurfural Selective hydrogenation nickel catalyst 2,5-Bis(hydroxymethyl)furan

EFFECT OF La2O3 AND CeO2 ON CH4-CO2 REFORMING nickel catalyst

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Journal of Energy Chemistry 1997年第2期 128-134页

作者： LI Shu-Ying FENG Zhong-Wei WANG Chang-You (Cl Lab., Institute of Coal Chemical Engineering, Taiyuan University of Technology Taiyuan, Shanxi 030024)YANG Xue-Ren REN Jie CHEN Yang-Guang (Institute of Coal Chemistry, The Chinese Academy of Sciences Taiy

The reforming of CH4 with CO2 was carried out on alumina supported nickel catalysts with or without La2O3 or CeO2. The catalysts were characterized by XRD and XPS techniques. XRD results show that La2O3 and CeO2 can reduce the interaction between NiO and γ-Al2O3,improve the dispersion of NiO and Ni, and inhibit the growth of Ni crystal during reaction. XPS results indicate that La2O3 and CeO2 have some effect on nickel in oxide state.

关键词： CH4-CO2 reforming nickel catalyst La2O3 CeO2