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Chemical Research in Chinese Universities 2009年第6期25卷 914-919页

作者： WU Bi-jun LIU Xiao-qin XIAO Ping State Power Environmental Protection Research Institute of China Guodian Corporation Nanjing 210031 P R. China Chemical Engineering Institute Nanjing University of Technology Nanjing 210009 P. R. China

The performance of Mn-W/TiO2 for selective catalytic reduction（SCR） of NOx with NH3 and its resistance to different concentrations of SO2 at various temperatures were investigated. The results show that WO3 increased the active sites and enhanced the strength of acid, so it was an effective promoter of MnOJTiO2. The NOx conversion on Mn-W/TiO2 ranges from 80.3% to 99.6% between 100 ℃to 350℃ at GHSV=18900 h 1, while N2 product selectivity changes from 100% to 98.7%. In the presence of 0.01% SO2 and 6% H20, NOx conversion maintained 98.5% at 120℃. The influence of more than 0.01% SO2 on the activity of MnOx-WO3/TiO2 will disappear if the temperature rises above 250℃. By means of heating and sweeping with He, the activity of the catalysts can be recovered. At 300℃, NOx conversion yielded 99% with 0.07% SO2 and reached the level of commercial V-W/TiO2 catalysts. The Mn-W/TiO2 catalyst showed excellent performance for SCR of NOx with NH3 in a wider range of temperature with strong tolerance to SO2.

关键词： Selective catalytic reduction NOx MnOx-WO3/TiO2 catalytic performance

Promoted catalytic performance of Ag-Mn bimetal catalysts synthesized through reduction route

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Journal of Environmental Sciences 2024年第3期137卷 358-369页

作者： Wenkai Hu Tao Guo Kaiyao Ma Xu Li Wangting Luo Mingzhi Wu Hao Guo Yaxin Zhang Wenfeng Shangguan School of Chemical Engineering and Technology Xinjiang UniversityUrumchi 830017China Research Center for Combustion and Environmental Technology Shanghai Jiao Tong UniversityShanghai 200240China

VOCs can exert great harm to both human and environment,and catalytic oxidation is believed to be an effective technique to eliminate these *** this paper,Ag-Mn bimetal catalysts with 10 wt.%of silver were synthesized using doping,impregnation,and reduction methods respectively,and then they were applied to the catalytic oxidation of *** series of characterizations it showed that the loading of silver using reduction method significantly resulted in improved physico-chemical properties of manganese oxides,such as larger surface area and pore volume,higher proportion of surface Mn~(3+)and Mn~(4+),stronger reducibility and more active of surface oxygen species,which were all beneficial to its catalytic *** a result,the Ag-Mn catalysts synthesized by reduction method showed a lower T_(90)value(equals to the temperature at which 90%of initial benzene was removed)of 203℃.Besides,both the used and fresh Ag-Mn catalysts synthesized by reduction method showed preferable stability in this research.

关键词： Ag-Mn Benzene oxidation catalytic performance Reduction route

The regulating effect of doping Cu on the catalytic performance of CO oxidative coupling to DMO on Pd_(x)Cu_(y)/GDY:A DFT study

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Green Energy & Environment 2022年第4期7卷 742-754页

作者： Juan Zhao Min Han Zhanhui Wang Lixia Ling Riguang Zhang Baojun Wang College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan030024China Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province Taiyuan University of TechnologyTaiyuan030024China

Rely on the density functional theory(DFT)calculation,the catalytic performance of Pd_(x)Cu_(y)/GDY(x=1,2,3,4;x+y≤4)for CO oxidative coupling reaction was *** Pdx/GDY(x=1,2,3,4)are not ideal catalyst for dimethyl oxalate(DMO)formation because byproduct dimethyl carbonate(DMC)is easily formed on Pd_(1)/GDY and Pd_(2)/GDY,and high activation energies are needed on Pd_(3)/GDY and Pd_(4)/*** the second metal Cu is doped to regulate the performance of Pdx/GDY(x=1,2,3,4).Doping Cu not only improve the activity of DMO formation,but more importantly,controlling the ratio of Cu:Pd can effectively regulate the selectivity of *** taking into account the activity and selectivity of the reaction for the preparation of DMO by CO oxidative coupling,the Pd_(1)Cu_(1)/GDY and Pd_(1)Cu_(2)/GDY with the activation energies of 105.2 and 99.2 kJ mol^(-1)to generate DMO show excellent catalytic activity and high DMO selectivity,which are considered as good catalysts for CO oxidative *** differential charge density analysis shows the decrease in the charge density of metal clusters is an important reason for improving the selectivity of the catalyst.

关键词： GDY Pd clusters Cu:Pd ratio DMO formation catalytic performance

Modulating the local coordination environment of single-atom catalysts for enhanced catalytic performance

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Nano Research 2020年第7期13卷 1842-1855页

作者： Xinyuan Li Hongpan Rong Jiatao Zhang Dingsheng Wang Yadong Li Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications Experimental Center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China Department of Chemistry Tsinghua UniversityBeijing 100084China

The local coordination environment of catalysts has been investigated ftor an extended period to obtain enhanced catalytic *** with the advancement of single-atom catalysts(SACs),research on the coordination environment has been advanced to the atomic *** surrounding coordination atoms of central metal atoms play important roles in their catalytic activity,selectivity and *** recent years,remarkable improvements of the catalytic performance of SACs have been achieved by the tailoring of coordination atoms,coordination numbers and second-or higher-coordination shells,which provided new opportunities for the further development of *** this review,the characterization of coordination environment,tailoring of the local coordination environment,and their related adjustable catalytic performance will be *** hope this review will provide new insights on further research of SACs.

关键词： single-atom catalysts coordination environment catalytic performance energy conversion

Synthesis,characterization and catalytic performance of nanosized iron-cobalt catalysts for light olefins production

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Journal of Natural Gas Chemistry 2011年第6期20卷 677-686页

作者： Mostafa Feyzi Asadollah Hassankhani Faculty of Chemistry Razi UniversityP.O.Box:+98-67149KermanshahIran Department of Materials Science International Center for ScienceHigh Technology & Environmental SciencesP.O.Box:+98-76315-117KermanIran

Nanosized Fe-Co catalysts were prepared by co-precipitation method and studied for the conversion of synthesis gas to light *** particular,the effects of a range of preparation variables such as Co/Fe molar ratios of the precipitation solution,pH value of precipitate,temperature of precipitation,promoters and loading of optimum promoter on the structure and catalytic performance are *** optimal nano catalyst for light olefins （C2-C4） production was obtained over the catalyst with Co/Fe molar ratio of 3/1 which promoted with 2 wt% *** results show that the best operational conditions were GHSV=2200 h^-1 （H2/CO=2/1） at 260℃ under atmospheric *** of catalysts were carried out using X-ray diffraction （XRD）,thermal gravimetric analysis （TGA）,differential scanning calorimetry （DSC）,scanning electron microscopy （SEM）,transmission electron microscopy （TEM） and N2 physisorption measurements such as Brunauer-Emmett-Teller （BET） and Barrett-Joyner-Halenda （BJH） methods.

关键词： light olefins catalytic performance operational condition characterization

The effect of hydrogen peroxide on properties of Ce0.35Zr0.55La0.055Pr0.045O2 oxides and the catalytic performance usedon Pd supported three-way catalyst

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Journal of Rare Earths 2017年第11期35卷 1092-1101页

作者： Qi wang Meisheng Cui Xiaowei Huang Yongke Hou Mei Yue Qiang Zhong YongqiZhang General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Co. Ltd Beijing 100088 China

In this study,two series of cerium zirconium mixed oxides CeZrLaPrOwere prepared under traditional co-precipitation and oxidation co-precipitation methods respectively. The physicochemical properties of the samples were compared under these two methods and assessed by XRD,Raman,BET,TEM,HTPR,OSC,XPS and catalysts measurements. The formation of homogeneity phase structure can be facilitated by changing the precipitating properties of Ce3+ under oxidation coprecipitation method, which is helpful to enhance the homogeneity of Ce and Zr at atomic ***’s more, it is conducive to remove impurities Na~+ and Cl~-by oxidation co-precipitation with hydrogen peroxide. The catalysts activities are related to both the redox properties and the textural properties of mixed oxides. The Pd-only TWCs supported on the CZLP-H-F exhibits better catalytic performance and thermal stability with wider air/fuel ratio operation window, lower light-off and full conversion temperatures of CHand NO. The homogeneity of phase structure for cerium zirconium mixed oxide can be predicted and deduced from detecting the atomic distribution uniformity of its precursor. So this work not only provides insights into the mechanisms for phase segregation of cerium zirconium mixed oxide, but also provides a guidance to improve homogeneity of cerium zirconium mixed oxide by adding additives.

关键词： Cerium zirconium mixed oxides Co-precipitation Hydrogen peroxide catalytic performance

Theoretically predicted innovative palladium stripe dopingcobalt(111) surface with excellent catalytic performance for carbonmonoxide oxidative coupling to dimethyl oxalate

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Chinese Journal of Chemical Engineering 2024年第9期73卷 235-243页

作者： Bingying Han Neng Shi Mengjie Dong Ye Liu Runping Ye Lixia Ling Riguang Zhang Baojun Wang State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030013China

Pd-based catalysts are extensively employed to catalyze CO oxidative coupling to generate DMO,while the expensive price and high usage of Pd hinder its massive application in industrial *** Pd-based catalysts with high efficiency and low Pd usage as well as expounding the catalytic mechanisms are significant for the *** this study,we theoretically predict that Pd stripe doping Co(111)surface exhibits excellent performance than pure Pd(111),Pd monolayer supporting on Co(111)and Pd single atom doping Co(111)surface,and clearly expound the catalytic mechanisms through the density functional theory(DFT)calculation and micro-reaction kinetic model *** is obtained that the favorable reaction pathway is COOCH_(3)-COOCH_(3)coupling pathway over these four catalysts,while the rate-controlling step is COOCH_(3)+CO+OCH_(3)→2COOCH_(3)on Pd stripe doping Co(111)surface,which is different from the case(2COOCH_(3)→DMO)on pure Pd(111),Pd monolayer supporting on Co(111)and Pd single atom doping Co(111)*** study can contribute a certain reference value for developing Pd-based catalysts with high efficiency and low Pd usage for CO oxidative coupling to DMO.

关键词： CO oxidative coupling to DMO Pd stripe doping Co(111)surface catalytic mechanism DFT calculation Micro-reaction kinetic model analysis catalytic performance

Preparation and catalytic performance of Microporous Polymer/Au Nanoparticles Composite Microspheres

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 464-468页

作者： GUO Chun ZHANG Lijuan ZHAO Yan LI Mengyuan WANG Xiaotao ZHANG Gaowen School of Materials and Chemical Engineering Hubei Provincial Key Laboratory of Green Materials for Light IndustryHubei University of TechnologyWuhan 430068China

Polystyrene crosslinked microspheres were prepared by soap-free emulsion polymerization using styrene (St) and divinylbenzene (DVB) as monomers;then,the microporous structure was knitted by the Friedel-Crafts alkylation reaction,and the Au nanoparticles (AuNPs) were loaded into the pores through thermal reduction,to obtain AuNPs/ hyper-crosslinked microporous polymer composite *** and particle-size test results show that the microspheres show good *** micropore analysis indicates that the specific surface area and the pore volume of the microporous polymer microspheres decrease with increasing DVB content,and when the DVB content is 0.1%,the specific surface area reaches a maximum of 1 174.6 m2/*** loading AuNPs,the specific surface area and the amount of micropores of the composite microspheres decrease *** results of XRD and XPS analyses suggest that HAuCl4 is reduced to *** composite microspheres show a good catalytic performance for the reduction catalyst of 4-nitrophenol.

关键词： microporous polystyrene microspheres Au nanoparticles hyper-crosslinking catalytic performance

Influence of the Substituents on Imino-aryl Ring of Mono(imino)pyrrole-NiⅡ Complexes to Their Ethylene Polymerization catalytic performance

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Chinese Journal of Structural Chemistry 2020年第6期39卷 1093-1102页

作者： SU Bi-Yun YAN Ting-Yu LI Xiao-Teng PAN Dan-Dan FAIDA Paison DING Li-Qin College of Chemistry and Chemical Engineering Xi'an Shiyou UniversityXi'an 110065China PetroChina Hohhot Petrochemical Company 010070China

In order to study the influence of substituents on imino-aryl rings of mono(imino)pyrrole-transition metal complexes to their ethylene polymerization performance,a series of mono(imine)pyrroles(L1-L3)were synthesized by microwave irradiation from 2-acetylpyrrole and a series of 2,6-position disubstituted anilines(substituent:H,Me,Et).A simplified synthetic method was introduced to prepare the corresponding nickel complexes NiL2(1~3)with direct condensation of mono(imine)pyrrole ligands and nickel *** the compounds were fully characterized by 1 H NMR,IR,EA,MS,and X-ray crystal *** L3(C16H20N2,Mr=240.34)belongs to the triclinic system,space group P1,with a=7.9606(19),b=9.028(2),c=11.205(3)?,the final R=0.0606 and wR=*** 3(C32H38N4Ni,Mr=537.37)belongs to the monoclinic system,space group C2/c with a=19.811(3),b=11.262(2),c=26.004(4)?,the final R=0.0388 and wR=*** crystal structures indicated that all the NiⅡcomplexes have similar tetra-coordinated geometries,in which the ligand chelated to the center nickel with a 2:1 molar *** properties of the NiⅡcomplexes for ethylene polymerization were systematically investigated,and the results showed a regular increase of catalytic activities with steric hindrance of the substituents on the imino-aryl ring of NiⅡcomplexes.

关键词： mono(imino)pyrrole ligand Ni11 complex crystal structure ethylene polymerization catalytic performance

Effects of Operating Conditions on the catalytic performance of HZSM-5 Zeolites in n-Pentane Cracking

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China Petroleum Processing & Petrochemical Technology 2021年第1期23卷 67-75页

作者： Hou Xu Zhao Liu Ma Zhenzhou Chen Bochong Feng Jingyuan Cui Tingting School of Chemical Engineering Changchun University of TechnologyChangchun 130012 Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012 Department of Chemistry Tsinghua UniversityBeijing 100084

In this work,n-pentane catalytic cracking over HZSM-5 zeolites was studied at 650°C under atmosphere pressure.A particular attention was paid to the measurement of n-pentane conversion,light olefins production,product distribution,coke deposit,*** indexes were defined to evaluate the effects of operating conditions on the catalytic performance of HZSM-5 *** was found that decreasing the weight hourly space velocity,increasing the reactant partial pressure,and increasing the carrier gas flow rate could inhibit C-H bond breaking and enhance the C-C bond breaking and hydride transfer reactions,leading to reduced alkenes selectivity,which suppressed the formation of external coke and alleviated the deactivation of HZSM-5 *** was deduced that the catalytic stability of HZSM-5 zeolites was improved at the cost of alkenes *** with decreasing the weight hourly space velocity and increasing the reactant partial pressure,increasing the carrier gas flow rate could enhance the diffusion process and protect alkenes from being consumed in coke formation in order to improve the catalytic stability of HZSM-5 zeolites with less reduction of alkenes selectivity.

关键词： operating conditions HZSM-5 zeolites catalytic performance n-pentane cracking light olefins