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Regioselective Polymerizations of α-Olefins with an α-Diamine Nickel catalyst

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Chinese Journal of Polymer Science 2019年第10期37卷 959-965,I0003页

作者： Heng Liao Jie Gao Liu Zhong Hai-Yang Gao Qing Wu School of Materials Science and Engineering PCFM Lab GD HPPC Lab Sun Yat-sen University

Polymerizations of linear α-olefins(CnH2n, CH2=CH―R, R = Cn-2) catalyzed by early transition metals typically afford amorphous polymers with alkyl chains(Cn-2), while chain-straightening polymerizations of α-olefins with nickel-based catalysts produce semicrystalline polyolefins. Polymerizations of various α-olefins were carried out using an α-diamine nickel catalyst with a significantly distorted chelating ring. The influences of temperature, monomer concentration, and chain length of α-olefins on polyolefin microstructure were examined in detail. The α-diamine nickel catalyst realized highly regioselective 2,1-insertion of α-olefins regardless of reaction temperature and monomer concentration. Increased chain length of α-olefins led to the formation of more linear *** polyolefins with high melting temperatures(Tm) were made from α-olefins through highly regioselective 2,1-insertion and precise chain-straightening.

关键词： Nickel catalyst α-Olefin Polymerization Regioselectivity Chain walking

catalyst-Packed Non-Thermal Plasma Reactor for Removal of Nitrogen Oxides

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Plasma Science and Technology 2003年第1期5卷 1603-1608页

作者： V.Ravi YoungSunMok B.S.Rajanikanth Ho-ChulKang DepartmentofHighVoltageEngineering IndianInstituteofScienceBangalore-560012India DepartmentofChemicalEngineering ChejuNationalUniversityAraCheju690-756SouthKorea

A single-stage plasma-catalytic reactor in which catalytic materials werepacked was used to remove nitrogen oxides. The packing material was scoria being made of variousmetal oxides including Al_2O_3, MgO, TiO_2, etc. Scoria was able to act not only as dielectricpellets but also as a catalyst in the presence of reducing agent such as ethylene and *** plasma discharge, scoria did not work well as a catalyst in the temperature range of 100 ℃to 200 ℃, showing less than 10% of NOx removal efficiency. When plasma is produced inside thereactor, the NOx removal efficiency could be increased to 60% in this temperature range.

关键词： plasma catalyst scoria nitrogen oxides removal

One-step conversion of syngas to light olefins over bifunctional metal-zeolite catalyst

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Chinese Journal of Chemical Engineering 2021年第8期34卷 101-110页

作者： Ce Du Linet Gapu Chizema Emmerson Hondo Mingliang Tong Qingxiang Ma Xinhua Gao Ruiqin Yang Peng Lu Noritatsu Tsubaki Zhejiang Provincial Key Lab for Chem.&Bio.Processing Technology of Farm Product School of Biological and Chemical EngineeringZhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Chemistry School of EngineeringUniversity of ToyamaGofuku 3190Toyama 930-8555Japan State Key Laboratory Cultivation Base of Natural Gas Conversion Ningxia UniversityYinchuan 750021China

Light olefins(C_(2)–C_(4))are fundamental building blocks for the manufacture of polymers,chemical intermediates,and *** this work,we realized a composite catalyst,comprising MnxZry oxides and SAPO-34 zeolite,which can convert syngas(CO+H_(2))into light *** oxide catalysts with different Mn/Zr molar ratios were facilely prepared using the coprecipitation method prior to physical mixing with SAPO-34 *** redox properties,surface morphology,electronic state,crystal structure,and chemical elemental composition of the catalysts were examined using H_(2)-TPR,SEM,XPS,XRD,and EDS techniques,*** reactions involved activation of CO and subsequent hydrogenation over the metal oxide catalyst,producing methanol and dimethyl ether as the main reaction intermediates,which then migrated onto SAPO-34 zeolite for light olefins *** of temperature,pressure and reactant gas flow rate on CO conversion and light olefins selectivity were investigated in *** Mn_(1)Zr_(2)/SAPO-34 catalyst(Mn/Zr ratio of 1:2)attained a CO conversion of 10.8%and light olefins selectivity of 60.7%,at an optimized temperature,pressure and GHSV of 380℃,3 MPa and 3000h^(−1) *** findings open avenues to exploit other metal oxides with CO activation capabilities for a more efficient syngas conversion and product selectivity.

关键词： catalyst C-C coupling CO activation Hydrogenation Light olefins Syngas

Preparation of solid acid catalyst SO4^2-/TiO2/γ-Al2O3 for esterification: A study on catalytic reaction mechanism and kinetics

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2696-2704页

作者： Ying Yuan Wenwei Jiang Jinjin Li School of Chemical Engineering Sichuan UniversityChengdu 610065China

In this work, a series of SO4^2-/TiO2/γ-Al2O3 solid acid catalysts were synthesized by impregnation method, in which nano-TiO2 was prepared by sol–gel method, and then the nano-TiO2 sol was loaded on porous γ-Al2O3 supporter through impregnation. The structure and property of catalyst were characterized by XRD, N2-BET,SEM, TEM, XPS, NH3-TPD, Pyridine-IR and FT-IR. In addition, the catalyst of chelate bidentate coordination acid center model was established. The catalytic performance test was carried out in the esterification of n-butyl alcohol with lauric acid and the catalyst showed excellent activity. The experimental results showed that the medium strength acid sites were more dominant active sites than the strong and weak acid sites for the rapid esterification reaction. Its kinetic behaviors and activation energy were studied for the esterification under the catalytic reaction condition.

关键词： Solid acid catalyst Nano-TiO2 Esterification Kinetics

Development and Electrochemical Studies of Ruthenium Based Mixed Oxide catalyst Electrodes for Chlorine Evolution

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Chemical Research in Chinese Universities 2002年第2期18卷 133-138页

作者： L.X.Yang J.P.G.Farr Department of Chemical and Processing Engineering University of Newcastle Merz CourtNewcastle upon Tyne NE17RU School of Metallurgy and Materials The University of Birmingham EdgbastonBirmingham B152TTUK

Experimental results are presented which allow comparison of the electrochemical performance of RuO 2/Ti, Ru 0 3 Sn 0 7 O 2/Ti and Ru 0 3 V 0 7 O 2/Ti catalysts prepared on a titanium substrate by thermal decomposition from respective precursors. The highest activity for chlorine evolution is observed on the Ru 0 3 V 0 7 O 2/Ti electrode, lower on Ru 0 3 Sn 0 7 O 2/Ti and least on RuO 2/Ti. Voltammograms obtained in the polarisable region are used to characterize the different electrodes. Further more an analysis of the catalytic activity and reaction kinetics of the developed electrodes in NaCl are presented.

关键词： catalyst Cl_(2) evolution Ruthenium oxide

Alternative Optimal Activity Distribution to the Classical Optimal Distribution in catalyst Pellets with Exergy and Entropy Consideration

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过程工程学报 2004年第4期4卷 372-379页

作者：毛在砂陆恩锡 Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Chem. Eng. Res. Inst. South China University of Technology GuangzhouGuangdong 510640 China

It is generally recognized that the optimal distribution of catalyst activity in a spherical catalyst is a Dirac d-function. However, catalyst with other alternative distribution may accomplish the same reaction task without necessarily concentrating the catalyst activity in an inside thin layer. Moreover, the alternative with activity on catalyst surface may offer higher reaction rate and better utilization of reaction heat (higher exergy output). Simple cases of first-order exothermal reactions, in particular when the catalyst is limited by the maximum working temperature, are presented to demonstrate the above advantages and to show the importance of studying the optimal activity distribution with the consideration on exergy maximization and entropy production minimization.

关键词： catalyst activity optimal distribution exergy entropy production energy integration

Molten salt-assisted synthesis of bulk CoOOH as a water oxidation catalyst

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Journal of Energy Chemistry 2020年第3期29卷 5-10页

作者： Sanzhao Song Hongliang Bao Xiao Lin Xian-Long Du Jing Zhou Linjuan Zhang Ning Chen Jun Hu Jian-Qiang Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Canadian Light Source University of SaskatchewanSaskatoon S7N 2V3Canada

Different sizes of layered CoOOH were synthesized by the molten-salt-assisted method at different temperatures.X-ray diffraction and scanning electron microscope studies reveal that CoOOH grew at(003)with increasing temperature,and its size can reach dozens of microns.X-ray absorption near edge structure and XPS studies demonstrate that the Co valence state of CoOOH-750 is trivalent,and X-ray Absorption Fine Structure shows that it had a higher symmetry and lower disorder degree,indicating that CoOOH-750 has higher crystallinity and Co3+.The results of electrochemical tests show that CoOOH-750 exhibited the best oxygen-evolution-reaction(OER)catalytic activity.

关键词： Molten-salt-assisted synthesis CoOOH Crystallinity Water oxidation catalyst

Petroleum coke conversion behavior in catalyst-assisted chemical looping combustion

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2417-2424页

作者： Xianyu Liu Huijun Ge Shiwei Ma Shangyi Yin Ping Lu Laihong Shen Hongcun Bai Wei Wang Tao Song School of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing 210023China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education Southeast UniversityNanjing 210096China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China SUMEC Complete Equip.&Eng.Co. LtdNanjing210018China

Efficiently using petroleum coke as fuel and reducing carbon emission meanwhile have become attractive in oil processing *** paper is focused on the application of Chemical Looping Combustion(CLC)with petroleum coke,with the purpose of investigating its combustion performance and effects of *** experiments were performed in a laboratory scale fluidized bed facility with a natural manganese-based oxygen *** results indicated that the coke conversion is very sensitive to reaction *** pre sent natural manganese-based oxygen carrier decorated by K has little effect on the improvement of coke ***,SEM-EDX,and H2-TPR were adopted to characterize the reacted oxygen carrier *** being decorated by K,the oxygen carrier's capacity of transferring oxygen was decrea sed.A calcination temperature above the melting point of K2 CO3(891℃)shows better oxygen transfer reactivity in comparison to the one calcined at a lower *** natural oxygen carrier used in the work has a high content of Si,which can easily react with K to form K(FeSi2 O6).Further,irrespective of reaction temperature,the coke conversion can be significantly enhanced by decorating the coke with K,with a demonstration of remarkably shorter reaction time,faster average coke gasification rate and higher average carbon conversion rate.

关键词： Chemical looping combustion Oxygen carrier catalyst Coke

Effect of cerium addition on catalytic performance of PtSnNa/ZSM-5 catalyst for propane dehydrogenation

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Journal of Natural Gas Chemistry 2012年第3期21卷 324-331页

作者： Mengwei Xue Yuming Zhou Yiwei Zhang Xuan Liu Yongzheng Duan Xiaoli Sheng School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189JiangsuChina School of Biochemical and Environmental Engineering Nanjing Xiaozhuang UniversityNanjing 211171JiangsuChina

The effect of cerium addition on the catalytic performance of propane dehydrogenation over PtSnNaIZSM-5 catalyst has been investigated by reaction tests and some physicochemical characterization such as XRD, BET, TEM, XPS, NH3-TPD, H2 chemisorption, TPR and TPO techniques. It has been found that with suitable amount of cerium addition, the platinum dispersion increased, while the carbon deposition tended to be eliminated easily. In these cases, the presence of cerium could not only realize the better distribution of metallic particles on the support, but also strengthen the interactions between Sn species and the support. Additionally, XPS spectra confirmed that more amounts of tin could exist in oxidized form, which was advantageous to the reaction. In our experiments, PtSnNaCe （1.1 wt%）/ZSM-5 catalyst exhibited the best catalytic performance. After running the reaction for 750 h, propane conversion was maintained higher than 30% with the corresponding selectivity to propylene of about 97%.

关键词： cerium Pt-Sn propane dehydrogenation catalyst