The on-board methanol steam reforming(MSR) has long been considered as an effective approach to insitu produce hydrogen for fuel cell vehicles(FCVs). However, the conventional MSR catalyst pellets suffer from easy bre...The on-board methanol steam reforming(MSR) has long been considered as an effective approach to insitu produce hydrogen for fuel cell vehicles(FCVs). However, the conventional MSR catalyst pellets suffer from easy breakage during the vehicle movement, leading to increased pressure drop and reduced system stability. Herein, we introduce an integrated method to prepare the highly controlled structured catalysts based on coupled processes: direct prototyping the structured substrate using digital light processing(DLP) 3D printing technology, in-situ dynamic crystallization of active components assisted by magnetic resonance imaging(MRI) and calcination. The synthesized catalyst owns a gradient layer of active component, and exhibits better MSR performance, higher mechanical strength, reduced pressure drop, higher Cu dispersion and better adhesion of active compounds when compared with the conventional powder and pellet catalysts. The demonstrated successful application proves the feasibility of developed method,which has great potential to be used for preparing precisely other monolithic catalysts with customized structures.展开更多
Surfactant-modified CeO_(2)@TiO_(2) core-shell nanostructure catalysts were prepared by coprecipitation with the addition of sodium dodecyl sulfonate(SDS),and their catalytic oxidation of dichloromethane(DCM) was stud...Surfactant-modified CeO_(2)@TiO_(2) core-shell nanostructure catalysts were prepared by coprecipitation with the addition of sodium dodecyl sulfonate(SDS),and their catalytic oxidation of dichloromethane(DCM) was studied.A 90% DCM conversion efficiency is obtained at 300℃ with the CeO_(2)@TiO_(2)SDS catalyst,and its catalytic stability in the 55 h test period is better than that of Ce/TiO_(2) and CeO_(2)@TiO_(2).Based on the characterization of CeO_(2)@TiO_(2)SDS,the dispersion of active components is promoted due to the inhibition of crystal growth with the introduction of SDS.The improvement of surface acidity and redox capacity is beneficial to the enhancement of catalytic activity.The higher adsorbed oxygen content on the surface of the CeO_(2)@TiO_(2)SDS catalyst is responsible for the better catalytic stability.Generally,a novel method was developed to design catalytic oxidation catalysts for the treatment of chlorinated volatile organic compounds in future applications.展开更多
Selective catalytic reduction of NO_(x)with ammonia(NH_(3)-SCR)is an efficient and established technology for removing NO_(x)emission from anthropogenic sources.The commercial de-NO_(x)catalysts based on V_(2)O_(5)-WO...Selective catalytic reduction of NO_(x)with ammonia(NH_(3)-SCR)is an efficient and established technology for removing NO_(x)emission from anthropogenic sources.The commercial de-NO_(x)catalysts based on V_(2)O_(5)-WO_(3)/TiO_(2)possess some significant drawbacks limiting their applicability,including narrow operating temperature window,biotoxicity,poor hydrothermal stability and SO_(2)/H_(2)O intolerance.To circumvent these shortcomings,modifications of existing V_(2)O_(5)-WO_(3)/TiO_(2)catalysts as well as development of novel catalysts have been investigated intensively.展开更多
AuCl3 loaded structured catalysts were prepared on SiC foam supported with pre-coated activated carbon layers. The catalytic properties of the structured catalysts towards hydrochlorination of acetylene were tested in...AuCl3 loaded structured catalysts were prepared on SiC foam supported with pre-coated activated carbon layers. The catalytic properties of the structured catalysts towards hydrochlorination of acetylene were tested in a fixed- bed reactor with the AuCl3 loaded on activated carbon pellets as a reference. For isopyknic catalysts, the structured catalyst with only one fifth of the Au amount as that was used on the reference catalyst exhibited even a little higher acetylene conversion and much better stability than the latter no matter what the gas hourly space velocities of acetylene were used. The results indicated that the more homogeneous distribution of AuCl3 particles and better heat transfer along the fixed-bed reactor originated from the low pressure drop and high thermal conductivity of the SiC foam supported structured catalysts might be able to account for their improved efficiency and stability. It is befieved that these novel structured C/Au catalysts can be potentially applied in VCM industrialization in view of their greatly reduced cost and much prolonged life.展开更多
Monolithic catalysts for CO_(2) methanation have become an active research area for the industrial development of Power-to-Gas technology.In this study,we developed a facile and reproducible synthesis strategy for the...Monolithic catalysts for CO_(2) methanation have become an active research area for the industrial development of Power-to-Gas technology.In this study,we developed a facile and reproducible synthesis strategy for the preparation of structured NiFe catalysts on washcoated cordierite monoliths for CO_(2) methanation.The NiFe catalysts were derived from in-situ grown layered double hydroxides(LDHs)via urea hydrolysis.The influence of different washcoat materials,i.e.,alumina and silica colloidal suspensions on the formation of LDHs layer was investigated,together with the impact of total metal concentration.NiFe LDHs were precipitated on the exterior surface of cordierite washcoated with alumina,while it was found to deposit further inside the channel wall of monolith washcoated with silica due to different intrinsic properties of the colloidal solutions.On the other hand,the thickness of in-situ grown LDHs layers and the catalyst loading could be increased by high metal concentration.The best monolithic catalyst(COR-AluCC-0.5M)was robust,having a thin and well-adhered catalytic layer on the cordierite substrate.As a result,high methane yield was obtained from CO_(2) methanation at high flow rate on this structured NiFe catalysts.The monolithic catalysts appeared as promising structured catalysts for the development of industrial methanation reactor.展开更多
Methylcyclohexane(MCH)serves as an ideal hydrogen carrier in hydrogen storage and transportation process.In the continuous production of hydrogen from MCH dehydrogenation,the rational design of energy-efficient cataly...Methylcyclohexane(MCH)serves as an ideal hydrogen carrier in hydrogen storage and transportation process.In the continuous production of hydrogen from MCH dehydrogenation,the rational design of energy-efficient catalytic way with good performance remains an enormous challenge.Herein,an internal electric heating(IEH)assisted mode was designed and proposed by the directly electrical-driven catalyst using the resistive heating effect.The Pt/Al2O_(3)on Fe foam(Pt/Al2O_(3)/FF)with unique threedimensional network structure was constructed.The catalysts were studied in a comprehensive way including X-ray diffraction(XRD),scanning electron microscopy(SEM)-mapping,in situ extended X-ray absorption fine structure(EXAFS),and in situ COFourier transform infrared(FTIR)measurements.It was found that the hydrogen evolution rate in IEH mode can reach up to above 2060 mmol·gPt^(−1)·min^(−1),which is 2–5 times higher than that of reported Pt based catalysts under similar reaction conditions in conventional heating(CH)mode.In combination with measurements from high-resolution infrared thermometer,the equations of heat transfer rate,and reaction heat analysis results,the Pt/Al2O_(3)/FF not only has high mass and heat transfer ability to promote catalytic performance,but also behaves as the heating component with a low thermal resistance and heat capacity offering a fast temperature response in IEH mode.In addition,the chemical adsorption and activation of MCH molecules can be efficiently facilitated by IEH mode,proved by the operando MCH-FTIR results.Therefore,the as-developed IEH mode can efficiently reduce the heat and mass transfer limitations and prominently boost the dehydrogenation performance,which has a broad application potential in hydrogen storage and other catalytic reaction processes.展开更多
Silicalite-1(S1)foam was functionalized by supporting manganese-cobalt(Mn-Co)mixed oxides to develop the structured hierarchical catalyst(Mn-Co@SlF)for catalytic combustion for the first time.The self-supporting S1 fo...Silicalite-1(S1)foam was functionalized by supporting manganese-cobalt(Mn-Co)mixed oxides to develop the structured hierarchical catalyst(Mn-Co@SlF)for catalytic combustion for the first time.The self-supporting S1 foam with hierarchical porosity was prepared via hydrothermal synthesis with polyurethane(PU)foam as the template.Subsequently,Mn-Co oxide nano sheets were uniformly grown on the surface of S1 foams under hydrothermal conditions to prepare the structured hierarchical catalyst with specific surface area of 354 m^2·g^-1,micropore volume of 0.141 cm^3·g^-1 and total pore volume of 0.217 cm3·g^-1,as well as a good capacity to adsorb toluene(1.7 mmol·g^-1 at p/p0=0.99).Comparative catalytic combustion of toluene of over developed structured catalyst Mn-Co@SlF was performed against the control catalysts of bulk Mn-Co@S1(i.e.,the crushed Mn-Co@SlF)and unsupported Mn-Co oxides(i.e.,Mn-Co).Mn-Co@SlF exhibited comparatively the best catalytic performance,that is,complete and stable toluene conversion at 2480 C over 65 h due to the synergy between Mn-Co oxides and S1 foam,which provided a large number of oxygen vacancies,high redox capacity.In addition,the hierarchical porous structure also improved the accessibility of active sites and facilitated the global mass transfer across the catalyst bed,being beneficial to the catalysis and catalyst longevity.展开更多
In light of the challenges associated with catalyst separation and recovery,as well as the low production efficiency resulting from intermittent operation for titanium silicalite-1(TS-1)catalyzed phenol hydroxylation ...In light of the challenges associated with catalyst separation and recovery,as well as the low production efficiency resulting from intermittent operation for titanium silicalite-1(TS-1)catalyzed phenol hydroxylation to dihydroxybenzene in the slurry bed,researchers keep on exploring the use of a continuous fixed bed to replace the slurry bed process in recent years.This study focuses on preparing a TS-1 coated structured catalyst on SiC foam,which exhibits significant process intensification in performance.We investigated the kinetics of this structured catalyst and compared it with those of extruded TS-1 catalyst;the dynamic equations of the two catalysts were obtained.It was observed that both catalysts followed E-R adsorption mechanism model,with an effective internal diffusion factor ratio between structured and extruded TS-1 of approximately 7.71.It was confirmed that the foamed SiC-based structured TS-1 catalyst exhibited significant improvements in phenol hydroxylation in fixed-bed reactor due to its well-developed pore structure,good thermal conductivity,excellent internal mass transfer performance,and short reactant diffusion distance,leading to higher utilization efficiency of active components.This finding also provides a foundation for designing and developing phenol hydroxylation processes in fixed-bed using structured catalysts through computational fluid dynamics calculations.展开更多
Carbon dioxide(CO_(2))can be efficiently converted and utilized through the CO_(2) methanation reaction,which has significant potential benefits for the environment and the economy.The contradiction between the thermo...Carbon dioxide(CO_(2))can be efficiently converted and utilized through the CO_(2) methanation reaction,which has significant potential benefits for the environment and the economy.The contradiction between the thermodynamics and kinetics of the CO_(2) methanation reaction process leads to low CO_(2) conversion at 200-350℃and low methane selectivity at 350-500℃.The utilization of catalysts can solve the contradiction between kinetics and thermodynamics,achieving high CO_(2) methanation efficiency at low temperatures.However,the poor thermal conductivity of powder catalysts leads to the rapid accumulation of heat,resulting in the formation of hot spots,which can cause the sintering or even deactivation of active species.To solve this problem,researchers have focused on monolithic catalysts with integrated reaction systems.This review categorizes the monolithic catalysts into two main groups based on their unique characteristics,namely structured catalysts and catalytic membrane reactors.The characteristics of these monolithic catalysts,commonly used support materials,preparation techniques,and their applications in the CO_(2) methanation reaction are discussed in depth.These studies provide theoretical basis and practical guidance for the design and optimization of structured catalysts and catalytic membrane reactors.Finally,challenges and prospects in the application of monolithic catalysts for the CO_(2) methanation reaction are proposed for the future development.展开更多
Carbon monoxide(CO)oxidation is crucial for pollutant removal and hydrogen purification.In recent years,copper–cerium(Cu–Ce)-mixed oxide catalysts have attracted significant attention due to their excellent activity a...Carbon monoxide(CO)oxidation is crucial for pollutant removal and hydrogen purification.In recent years,copper–cerium(Cu–Ce)-mixed oxide catalysts have attracted significant attention due to their excellent activity and stability in CO oxida-tion.This study presents an innovative,environmentally friendly electrosynthesis method for producing stable,structured Cu–Ce catalysts in mesh form.This approach addresses the limitations of traditional pellet catalysts,such as fragility and poor thermal conductivity.The results demonstrated that incorporating cerium(Ce)enhanced the catalytic activity for CO oxidation threefold.A series of in situ characterizations revealed that the introduction of Ce led to the formation of a Cu–Ce mixed oxide solid solution,which significantly improved catalytic performance.Furthermore,higher pretreatment tem-peratures facilitated the decomposition of Ce compounds(nitrate and hydroxide),which promotes the formation of Cu–Ce solid solutions and increases the concentration of active intermediate species(Cu^(+)-CO)during the reaction.This process ultimately enhanced the catalyst’s activity.展开更多
The present article studies the effect of CeO2 and A1203 on the activity of Pd/Co304/cordierite catalyst in conversion of NO, CO, CnHm. The catalysts were characterized by temperature programmed reduction with hydroge...The present article studies the effect of CeO2 and A1203 on the activity of Pd/Co304/cordierite catalyst in conversion of NO, CO, CnHm. The catalysts were characterized by temperature programmed reduction with hydrogen, X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. It is shown that the effect of CeO2 on the properties of Pd/C03 O4/cordierite catalyst depends on preparation method. The catalyst obtained by co-deposition of cerium and cobalt oxides has higher activity in CO oxidation （CO ＋ 02 and CO ＋ NO） and total hexane oxidation （C6H14 ＋ 02）. Such phenomenon is probably caused by more than stoichiometric amount of formed oxygen vacancies, an increase in both mobility of surface oxygen and dispersity of components in the catalytic composition. It is demonstrated that CeO2 addition promotes the SO2 resistance of Pd/C03 O4/cordierite. The second support decreases the activity of Pd/Co3Oa/cordierite catalyst in the reactions of CO and C6H14 with oxygen because of COA1204 formation.展开更多
Pd@Ru bimetallic nanoparticles deposited on carbon black electro-catalysts have been fabricated by microwave-assisted polyol reduction method and investigated for methanol electro-oxidation （MEO）. The structure and ...Pd@Ru bimetallic nanoparticles deposited on carbon black electro-catalysts have been fabricated by microwave-assisted polyol reduction method and investigated for methanol electro-oxidation （MEO）. The structure and electro-catalytic properties of the as-prepared catalysts were characterized by XRD, SEM, TEM and cyclic voltammetry （CV） techniques. The results showed that the introduction of Ru element （2-10 wt%） into Pd 20 wt%/C （hereafter, denoted as Pd/C） produced a series of core-shell structured binary catalysts. Pd@Ru 5 wt%/C （hereafter, denoted as Pd@Rus/C） catalyst displayed the highest catalytic activity towards MEO. And the mass activity of Pd@Ru5/C electrode catalyst at E = -0.038 V （vs. Hg/HgO） was 1.42 times higher than that of Pd/C electrode catalyst. In addition, the relationship between the catalytic stability for MEO on Pd@Ru/C catalysts and the value of dbp/dfp （the ratio of MEO peak current density in the negative scan and positive scan） were also investigated. The result demonstrated that Pd@Rus/C offering the smallest value of Jbp/Jfp displayed the best stable catalytic performance.展开更多
Novel composite material with a wide pore distribution was synthesized by an in situ technique using spent FCC catalyst as raw material. The characterization results indicated that the composite material contained 56....Novel composite material with a wide pore distribution was synthesized by an in situ technique using spent FCC catalyst as raw material. The characterization results indicated that the composite material contained 56.7% of zeolite Y and exhibited a much larger specific surface area and pore volume as well as strong hydrothermal stability. Fluid catalytic cracking(FCC) catalyst was prepared based on the composite material. The results indicated that the as-prepared catalyst possessed a unique pore structure that was advantageous to the diffusion-controlled reactions. In addition, the attrition resistance, activity and hydrothermal stability of the studied catalyst were superior to those of the reference catalyst. The catalyst also exhibited excellent nickel and vanadium passivation performance, strong bottoms upgrading selectivity, and better gasoline and coke selectivity. In comparison to the reference catalyst, the yields of the gasoline and light oil increased by 1.61 and 1.31 percentage points, respectively, and the coke yield decreased by 0.22 percentage points, and the olefin content in the produced gasoline reduced by 2.51 percentage points, with the research octane number increased by 0.7 unit.展开更多
The Mo modified Ni/Al_2O_3 catalysts were prepared and sulfided at different temperatures, and their catalytic activity for thioetherification of mercaptans and olefins(or dienes), hydrogenation of dienes and olefins ...The Mo modified Ni/Al_2O_3 catalysts were prepared and sulfided at different temperatures, and their catalytic activity for thioetherification of mercaptans and olefins(or dienes), hydrogenation of dienes and olefins in the thioetherification process using fluidized catalytic cracking(FCC) naphtha as the feedstock was investigated. In order to disclose the correlation between the physicochemical characteristics of catalysts and their catalytic activity, the surface structures and properties of the catalysts sulfided at different temperatures were characterized by the high resolution transmission electronic microscopy(HRTEM), X-ray photoelectron spectroscopy(XPS) and H2-temperature programmed reduction(H_2-TPR) technique. The results showed that an increase of sulfurization temperature not only could promote the sulfurization degree of active metals on the catalysts, but also could adjust the micro-morphology of active species. These changes could improve the catalytic performance of thioetherification, and hydrogenation of dienes and olefins. However, an excess sulfurization temperature was more easily to upgrade the ability of the catalyst for hydrogenation of olefins, which could lead to a decrease of the octane number of the product. It was also showed that a moderate sulfurization temperature not only could improve the catalytic performance of thioetherification and hydrogenation of dienes but also could control hydrogenation of olefins.展开更多
A new carbon bridged cyclopentadienyl chromium complex of the type [（C5H4）C（CH3）2 CH2（C5H4N）]CrCl2 was prepared by treatment of CrCl3·（THF）3 in THF solution with the lithium salt of ligand containing cycl...A new carbon bridged cyclopentadienyl chromium complex of the type [（C5H4）C（CH3）2 CH2（C5H4N）]CrCl2 was prepared by treatment of CrCl3·（THF）3 in THF solution with the lithium salt of ligand containing cyclopentadienyl and pyridyl groups. The chromium complex was characterized by 1H NMR and elemental analysis（EA）, and the crystal structure was determined by X-ray diffraction analysis. Activated by Al（i-Bu）3, the chromium complex displayed a very high activity for methyl methacrylate（MMA） polymerization. After 24 hours,more than 95.5% MMA was converted to polymethyl methacrylate（PMMA） with a viscosity average molecular weight（Wη） of 416000 g·mol-1 at 60 ℃ for MMA/ Al（i-Bu）3 /chromium catalyst molar ratio of up to 2000：20：1. Effects of temperature, molar ratios of MMA/catalyst and catalyst/cocatalyst on the polymerization have been studied. The high conversion of MMA and high molecular weight of PMMA with narrow molecular weight distribution is caused by the unique stable active site formed by the new chromium complex and aluminum cocatalyst.展开更多
Single-atom dispersed carbon nitride photocatalysts have been extensively associated with clean energy conversion,storage and utilization.However,it is still a challenge to elucidate the relationship between the elect...Single-atom dispersed carbon nitride photocatalysts have been extensively associated with clean energy conversion,storage and utilization.However,it is still a challenge to elucidate the relationship between the electronic structure of catalysts and their photocatalytic properties.In this work,single atom Ag/C_(3)N_(4)catalysts have been prepared via pyrolyzing cyanuric acid,AgNO_(3)and melamine as precursors.We observe that their photocatalytic activity increases on increasing the concentration of Ag from 0.32%to 0.53%,and subsequently decreases on further increasing the concentration of Ag,which indicates that the concentration of Ag atoms can control the performance of single-atom catalysts.Deep investigations suggest that the concentration of Ag atoms can modulate the bottom of the conduction band(CB)and the maximum of the valence band(VB).The higher the bottom of the CB is,the better the performance of catalysts is.In contrast to bulk carbon nitride,the rate constants of the optimized single-atom photocatalyst Ag/C_(3)N_(4)with 0.53%Ag for rhodamine B(RhB)and tetracycline(TC)degradation are enhanced approximately 165.3 and 24.9 times,respectively.Furthermore,the ESR spectrum shows that the superoxide radical plays a major role in the photocatalytic process.This work provides a new insight into the structure–property relationship and our strategy provides guidance for the synthesis of other single-atom photocatalysts.展开更多
Residual ions introduced during catalyst synthesis can significantly impact both the structure and performance of the catalyst.Despite their crucial role,the effects of these residual ions are frequently overlooked in...Residual ions introduced during catalyst synthesis can significantly impact both the structure and performance of the catalyst.Despite their crucial role,the effects of these residual ions are frequently overlooked in catalyst design and optimization.This review systematically surveys the characteristics and sources of typical residual ions in catalytic systems,including halogen anions,acidic anions,and alkali metal cations.It also examines their impact on both the supports and active metals of supported catalysts,as well as the alterations in surface,crystal structure,and chemical states of non-supported catalysts.The effects of residual ions on the performance of these catalysts in catalytic reactions such as oxidation and hydrogenation are discussed in detail.Additionally,the influence mechanism of residual ions on the catalysts is further explored,with a focus on their promotion and inhibition roles in catalytic processes,thus providing insights for the development of more efficient and durable catalysts.A summary finally provides an outlook on future approaches to advance catalyst preparation and mitigate the adverse effects of residual ions in catalysis.展开更多
The effects of reaction solvent, the properties of Sb 4O 5Cl 2 material and the ligand additives on the reaction rate and polymorph of antimony white(Sb 2O 3) in the reaction of Sb 4O 5Cl 2 transforming into S...The effects of reaction solvent, the properties of Sb 4O 5Cl 2 material and the ligand additives on the reaction rate and polymorph of antimony white(Sb 2O 3) in the reaction of Sb 4O 5Cl 2 transforming into Sb 2O 3 have been investigated by XRD and IR method. It is revealed that the reaction solvent and the properties of Sb 4O 5Cl 2 are the key factors affecting the reaction rate. The polymorph of antimony trioxides is determined by the reaction mechanism, i.e. the coordination state of the antimony activated complex. Adding a little ligand such as EDTA is the most economical and effective method of synthesizing cubic antimony white(Sb 2O 3)in hydrometallurgical transformation process.展开更多
The title complex bis{4-chloro-2-[（6-methyl-pyridin-2-ylimino）-methyl]-phenol}-palladium（Ⅱ）（C_（26）H_（20）Cl_2N_4O_2Pd） has been synthesized by the reaction of 4-chloro-2-[（6-methylpyridin- 2-ylimino）-methy...The title complex bis{4-chloro-2-[（6-methyl-pyridin-2-ylimino）-methyl]-phenol}-palladium（Ⅱ）（C_（26）H_（20）Cl_2N_4O_2Pd） has been synthesized by the reaction of 4-chloro-2-[（6-methylpyridin- 2-ylimino）-methyl]-phenol with Pd（CH_3COO）_2, and characterized by IR spectrum and elemental analysis. Single-crystal X-ray diffraction analysis results further confirmed the molecular structures. The crystal belongs to the monoclinic system, space group P2_1/c with a = 4.1324（2）, b = 23.5432（16）, c = 11.8943（8） A, β = 91.238（5）o, V = 1156.93（12） ？~3, C_（26）H_（20）Cl_2N_4O_2Pd, M_r = 597.76, Z = 2, D_c = 1.716 g/cm^3, μ = 1.067 mm^（-1）, F（000） = 600, the final R = 0.0247 and w R = 0.0677（I 〉 2σ（I））. In the presence of methylaluminoxane（MAO）, the complex exhibits excellent catalytic activities（1.737×10~7 g of PNB（mol of Pd）^（-1）·h^（-1）） in the vinyl polymerization of norbornene.展开更多
The title complex bis{1-{[（6-ethyl-2-pyridinyl）imino]methylenyl}-2-naphthale- nolato-N,O}-nickel（lI） （C36H32NnO2Ni） has been synthesized by the reaction of l-{[（6-ethyl-2- pyridinyl）imino]methylenyl}-2-naphtha...The title complex bis{1-{[（6-ethyl-2-pyridinyl）imino]methylenyl}-2-naphthale- nolato-N,O}-nickel（lI） （C36H32NnO2Ni） has been synthesized by the reaction of l-{[（6-ethyl-2- pyridinyl）imino]methylenyl}-2-naphthalenol with Ni（CH3COO）2·4H2O, and characterized by IR spectrum, elemental analysis and TG. The complicated space structure has been confirmed by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 11.410（4）, b = 14.382（4）, c = 18.121（6） ,A, β = 97.147（6）% V= 2950.5（16）A3, C36H32N4O2Ni, Mr = 611.37, Z = 4, Dc = 1.376 g/cm3, μ = 0.698 mm-1 F（000） = 1280, the final R = 0.0519 and wR = 0.1493 （1 〉2σ（I））. This title compound was used as precatalysts for the polymerisation of norbornene. When activated with MAO, the complex exhibited excellent catalytic activity up to 1.98 × 107 g ofPNB （mol of Ni）-1 h-1 with high monomer conversion.展开更多
基金supported by the Youth Innovation Promotion Association of Chinese Academy of Sciencesthe Key Technical Personnel of Chinese Academy of Sciences+1 种基金the STS Program of Chinese Academy of Sciences (No. KFJJ-STS-SCYD-302)the National Natural Science Foundation of China (22108288)。
文摘The on-board methanol steam reforming(MSR) has long been considered as an effective approach to insitu produce hydrogen for fuel cell vehicles(FCVs). However, the conventional MSR catalyst pellets suffer from easy breakage during the vehicle movement, leading to increased pressure drop and reduced system stability. Herein, we introduce an integrated method to prepare the highly controlled structured catalysts based on coupled processes: direct prototyping the structured substrate using digital light processing(DLP) 3D printing technology, in-situ dynamic crystallization of active components assisted by magnetic resonance imaging(MRI) and calcination. The synthesized catalyst owns a gradient layer of active component, and exhibits better MSR performance, higher mechanical strength, reduced pressure drop, higher Cu dispersion and better adhesion of active compounds when compared with the conventional powder and pellet catalysts. The demonstrated successful application proves the feasibility of developed method,which has great potential to be used for preparing precisely other monolithic catalysts with customized structures.
基金Project supported by the Science and Technology Department of Jiangsu Province (BE2016769)the Natural Science Foundation of Jiangsu Province (BK20171466 and BK20180718)。
文摘Surfactant-modified CeO_(2)@TiO_(2) core-shell nanostructure catalysts were prepared by coprecipitation with the addition of sodium dodecyl sulfonate(SDS),and their catalytic oxidation of dichloromethane(DCM) was studied.A 90% DCM conversion efficiency is obtained at 300℃ with the CeO_(2)@TiO_(2)SDS catalyst,and its catalytic stability in the 55 h test period is better than that of Ce/TiO_(2) and CeO_(2)@TiO_(2).Based on the characterization of CeO_(2)@TiO_(2)SDS,the dispersion of active components is promoted due to the inhibition of crystal growth with the introduction of SDS.The improvement of surface acidity and redox capacity is beneficial to the enhancement of catalytic activity.The higher adsorbed oxygen content on the surface of the CeO_(2)@TiO_(2)SDS catalyst is responsible for the better catalytic stability.Generally,a novel method was developed to design catalytic oxidation catalysts for the treatment of chlorinated volatile organic compounds in future applications.
基金the China Scholarship Council(No.202004910329)for awarding a scholarshipthe Department of Chemistry,Technical University of Denmark is acknowledged for supporting the work.
文摘Selective catalytic reduction of NO_(x)with ammonia(NH_(3)-SCR)is an efficient and established technology for removing NO_(x)emission from anthropogenic sources.The commercial de-NO_(x)catalysts based on V_(2)O_(5)-WO_(3)/TiO_(2)possess some significant drawbacks limiting their applicability,including narrow operating temperature window,biotoxicity,poor hydrothermal stability and SO_(2)/H_(2)O intolerance.To circumvent these shortcomings,modifications of existing V_(2)O_(5)-WO_(3)/TiO_(2)catalysts as well as development of novel catalysts have been investigated intensively.
基金supported by the National Key Technology R&D Program of China with Grant No.2011BAE03B07
文摘AuCl3 loaded structured catalysts were prepared on SiC foam supported with pre-coated activated carbon layers. The catalytic properties of the structured catalysts towards hydrochlorination of acetylene were tested in a fixed- bed reactor with the AuCl3 loaded on activated carbon pellets as a reference. For isopyknic catalysts, the structured catalyst with only one fifth of the Au amount as that was used on the reference catalyst exhibited even a little higher acetylene conversion and much better stability than the latter no matter what the gas hourly space velocities of acetylene were used. The results indicated that the more homogeneous distribution of AuCl3 particles and better heat transfer along the fixed-bed reactor originated from the low pressure drop and high thermal conductivity of the SiC foam supported structured catalysts might be able to account for their improved efficiency and stability. It is befieved that these novel structured C/Au catalysts can be potentially applied in VCM industrialization in view of their greatly reduced cost and much prolonged life.
文摘Monolithic catalysts for CO_(2) methanation have become an active research area for the industrial development of Power-to-Gas technology.In this study,we developed a facile and reproducible synthesis strategy for the preparation of structured NiFe catalysts on washcoated cordierite monoliths for CO_(2) methanation.The NiFe catalysts were derived from in-situ grown layered double hydroxides(LDHs)via urea hydrolysis.The influence of different washcoat materials,i.e.,alumina and silica colloidal suspensions on the formation of LDHs layer was investigated,together with the impact of total metal concentration.NiFe LDHs were precipitated on the exterior surface of cordierite washcoated with alumina,while it was found to deposit further inside the channel wall of monolith washcoated with silica due to different intrinsic properties of the colloidal solutions.On the other hand,the thickness of in-situ grown LDHs layers and the catalyst loading could be increased by high metal concentration.The best monolithic catalyst(COR-AluCC-0.5M)was robust,having a thin and well-adhered catalytic layer on the cordierite substrate.As a result,high methane yield was obtained from CO_(2) methanation at high flow rate on this structured NiFe catalysts.The monolithic catalysts appeared as promising structured catalysts for the development of industrial methanation reactor.
基金the National Natural Science Foundation of China(Nos.22225807,21961132026,21878331,22021004,and 22109177)the National Key Research and Development Program(Nos.2020YFA0210903 and 2021YFA1501304)+4 种基金the PetroChina research institute of petroleum processing program(Nos.PRIKY21057 and PRIKY 21199)the Fundamental Research Funds for the Central Universities(No.2462020BJRC008)the support of Energy Internet Research Center,China University of Petroleum(Beijing),Haihe Laboratory of Sustainable Chemical Transformations(No.CYZC202105)the Beijing Synchrotron Radiation Facility(BSRF)Shanghai Synchrotron Radiation Facility(SSRF)during the XAFS measurements at the beamline of 1W1B,1W2B,and BL11B.
文摘Methylcyclohexane(MCH)serves as an ideal hydrogen carrier in hydrogen storage and transportation process.In the continuous production of hydrogen from MCH dehydrogenation,the rational design of energy-efficient catalytic way with good performance remains an enormous challenge.Herein,an internal electric heating(IEH)assisted mode was designed and proposed by the directly electrical-driven catalyst using the resistive heating effect.The Pt/Al2O_(3)on Fe foam(Pt/Al2O_(3)/FF)with unique threedimensional network structure was constructed.The catalysts were studied in a comprehensive way including X-ray diffraction(XRD),scanning electron microscopy(SEM)-mapping,in situ extended X-ray absorption fine structure(EXAFS),and in situ COFourier transform infrared(FTIR)measurements.It was found that the hydrogen evolution rate in IEH mode can reach up to above 2060 mmol·gPt^(−1)·min^(−1),which is 2–5 times higher than that of reported Pt based catalysts under similar reaction conditions in conventional heating(CH)mode.In combination with measurements from high-resolution infrared thermometer,the equations of heat transfer rate,and reaction heat analysis results,the Pt/Al2O_(3)/FF not only has high mass and heat transfer ability to promote catalytic performance,but also behaves as the heating component with a low thermal resistance and heat capacity offering a fast temperature response in IEH mode.In addition,the chemical adsorption and activation of MCH molecules can be efficiently facilitated by IEH mode,proved by the operando MCH-FTIR results.Therefore,the as-developed IEH mode can efficiently reduce the heat and mass transfer limitations and prominently boost the dehydrogenation performance,which has a broad application potential in hydrogen storage and other catalytic reaction processes.
基金financial support from the Key Projects of Natural Science Foundation of Liaoning Province(2018010047-301)the Shenyang National Laboratory for Materials Science for his research(Y8L6641161)+1 种基金financial support from the National Key R&D Program of China(2016YFB0501303)funding from European Union's Horizon 2020 research and innovation programme under grant agreement No.872102。
文摘Silicalite-1(S1)foam was functionalized by supporting manganese-cobalt(Mn-Co)mixed oxides to develop the structured hierarchical catalyst(Mn-Co@SlF)for catalytic combustion for the first time.The self-supporting S1 foam with hierarchical porosity was prepared via hydrothermal synthesis with polyurethane(PU)foam as the template.Subsequently,Mn-Co oxide nano sheets were uniformly grown on the surface of S1 foams under hydrothermal conditions to prepare the structured hierarchical catalyst with specific surface area of 354 m^2·g^-1,micropore volume of 0.141 cm^3·g^-1 and total pore volume of 0.217 cm3·g^-1,as well as a good capacity to adsorb toluene(1.7 mmol·g^-1 at p/p0=0.99).Comparative catalytic combustion of toluene of over developed structured catalyst Mn-Co@SlF was performed against the control catalysts of bulk Mn-Co@S1(i.e.,the crushed Mn-Co@SlF)and unsupported Mn-Co oxides(i.e.,Mn-Co).Mn-Co@SlF exhibited comparatively the best catalytic performance,that is,complete and stable toluene conversion at 2480 C over 65 h due to the synergy between Mn-Co oxides and S1 foam,which provided a large number of oxygen vacancies,high redox capacity.In addition,the hierarchical porous structure also improved the accessibility of active sites and facilitated the global mass transfer across the catalyst bed,being beneficial to the catalysis and catalyst longevity.
基金National Key Research and Development Program(Grant No.2023YFB3810600)National Natural Science Foundation of China(Grant No.2237081611)+1 种基金European Union’s Horizon 2020 Research and Innovation Program(Grant No.872102)Natural Science Foundation of Liaoning Province(Grant No.2022-MS-002).
文摘In light of the challenges associated with catalyst separation and recovery,as well as the low production efficiency resulting from intermittent operation for titanium silicalite-1(TS-1)catalyzed phenol hydroxylation to dihydroxybenzene in the slurry bed,researchers keep on exploring the use of a continuous fixed bed to replace the slurry bed process in recent years.This study focuses on preparing a TS-1 coated structured catalyst on SiC foam,which exhibits significant process intensification in performance.We investigated the kinetics of this structured catalyst and compared it with those of extruded TS-1 catalyst;the dynamic equations of the two catalysts were obtained.It was observed that both catalysts followed E-R adsorption mechanism model,with an effective internal diffusion factor ratio between structured and extruded TS-1 of approximately 7.71.It was confirmed that the foamed SiC-based structured TS-1 catalyst exhibited significant improvements in phenol hydroxylation in fixed-bed reactor due to its well-developed pore structure,good thermal conductivity,excellent internal mass transfer performance,and short reactant diffusion distance,leading to higher utilization efficiency of active components.This finding also provides a foundation for designing and developing phenol hydroxylation processes in fixed-bed using structured catalysts through computational fluid dynamics calculations.
基金the National Natural Science Foundation of China(22325804 and 22308148)the Natural Science Foundation of Jiangsu Province(BK20230344)+1 种基金the Natural Science Research Project of Jiangsu University(22KJB610001)the Jiangsu Funding Program for Excellent Postdoctoral Talent(2023ZB505)。
文摘Carbon dioxide(CO_(2))can be efficiently converted and utilized through the CO_(2) methanation reaction,which has significant potential benefits for the environment and the economy.The contradiction between the thermodynamics and kinetics of the CO_(2) methanation reaction process leads to low CO_(2) conversion at 200-350℃and low methane selectivity at 350-500℃.The utilization of catalysts can solve the contradiction between kinetics and thermodynamics,achieving high CO_(2) methanation efficiency at low temperatures.However,the poor thermal conductivity of powder catalysts leads to the rapid accumulation of heat,resulting in the formation of hot spots,which can cause the sintering or even deactivation of active species.To solve this problem,researchers have focused on monolithic catalysts with integrated reaction systems.This review categorizes the monolithic catalysts into two main groups based on their unique characteristics,namely structured catalysts and catalytic membrane reactors.The characteristics of these monolithic catalysts,commonly used support materials,preparation techniques,and their applications in the CO_(2) methanation reaction are discussed in depth.These studies provide theoretical basis and practical guidance for the design and optimization of structured catalysts and catalytic membrane reactors.Finally,challenges and prospects in the application of monolithic catalysts for the CO_(2) methanation reaction are proposed for the future development.
基金supported by the National Key R&D Program of China(No.2022YFB3805504)the National Natu-ral Science Foundation of China(No.22078089)+2 种基金the Shanghai Pilot Program for Basic Research(No.22TQ1400100-7)the Basic Research Program of Science and Technology Commission of Shanghai Munici-pality(No.22JC1400600)the Fundamental Research Funds for the Central Universities.
文摘Carbon monoxide(CO)oxidation is crucial for pollutant removal and hydrogen purification.In recent years,copper–cerium(Cu–Ce)-mixed oxide catalysts have attracted significant attention due to their excellent activity and stability in CO oxida-tion.This study presents an innovative,environmentally friendly electrosynthesis method for producing stable,structured Cu–Ce catalysts in mesh form.This approach addresses the limitations of traditional pellet catalysts,such as fragility and poor thermal conductivity.The results demonstrated that incorporating cerium(Ce)enhanced the catalytic activity for CO oxidation threefold.A series of in situ characterizations revealed that the introduction of Ce led to the formation of a Cu–Ce mixed oxide solid solution,which significantly improved catalytic performance.Furthermore,higher pretreatment tem-peratures facilitated the decomposition of Ce compounds(nitrate and hydroxide),which promotes the formation of Cu–Ce solid solutions and increases the concentration of active intermediate species(Cu^(+)-CO)during the reaction.This process ultimately enhanced the catalyst’s activity.
基金supported by the National Specific-Purpose Scientific and Technical Program of Ukraine "Nanotechnology and Nanomaterials" (No.0110U005685)the Program of National Academy of Sciences of Ukraine "Fundamental Problems of Nanos-tructure Systems, Nanomaterials, Nanotechnologies" (No.KPKV 6541030)
文摘The present article studies the effect of CeO2 and A1203 on the activity of Pd/Co304/cordierite catalyst in conversion of NO, CO, CnHm. The catalysts were characterized by temperature programmed reduction with hydrogen, X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. It is shown that the effect of CeO2 on the properties of Pd/C03 O4/cordierite catalyst depends on preparation method. The catalyst obtained by co-deposition of cerium and cobalt oxides has higher activity in CO oxidation （CO ＋ 02 and CO ＋ NO） and total hexane oxidation （C6H14 ＋ 02）. Such phenomenon is probably caused by more than stoichiometric amount of formed oxygen vacancies, an increase in both mobility of surface oxygen and dispersity of components in the catalytic composition. It is demonstrated that CeO2 addition promotes the SO2 resistance of Pd/C03 O4/cordierite. The second support decreases the activity of Pd/Co3Oa/cordierite catalyst in the reactions of CO and C6H14 with oxygen because of COA1204 formation.
基金supported by the National Basic Research Program of China(2013CB934001)the Natural Science Foundation of Beijing(2051001)the Natural Science Foundation of China(51074011)
文摘Pd@Ru bimetallic nanoparticles deposited on carbon black electro-catalysts have been fabricated by microwave-assisted polyol reduction method and investigated for methanol electro-oxidation （MEO）. The structure and electro-catalytic properties of the as-prepared catalysts were characterized by XRD, SEM, TEM and cyclic voltammetry （CV） techniques. The results showed that the introduction of Ru element （2-10 wt%） into Pd 20 wt%/C （hereafter, denoted as Pd/C） produced a series of core-shell structured binary catalysts. Pd@Ru 5 wt%/C （hereafter, denoted as Pd@Rus/C） catalyst displayed the highest catalytic activity towards MEO. And the mass activity of Pd@Ru5/C electrode catalyst at E = -0.038 V （vs. Hg/HgO） was 1.42 times higher than that of Pd/C electrode catalyst. In addition, the relationship between the catalytic stability for MEO on Pd@Ru/C catalysts and the value of dbp/dfp （the ratio of MEO peak current density in the negative scan and positive scan） were also investigated. The result demonstrated that Pd@Rus/C offering the smallest value of Jbp/Jfp displayed the best stable catalytic performance.
基金provided by the National Natural Science Foundation of China(No.21371055)the Hunan provincial Natural Science Foundation of China(No.11JJ2008)the Hunan provincial Colleges and Universities Innovation Platform Open Fund Project(No.15K049)
文摘Novel composite material with a wide pore distribution was synthesized by an in situ technique using spent FCC catalyst as raw material. The characterization results indicated that the composite material contained 56.7% of zeolite Y and exhibited a much larger specific surface area and pore volume as well as strong hydrothermal stability. Fluid catalytic cracking(FCC) catalyst was prepared based on the composite material. The results indicated that the as-prepared catalyst possessed a unique pore structure that was advantageous to the diffusion-controlled reactions. In addition, the attrition resistance, activity and hydrothermal stability of the studied catalyst were superior to those of the reference catalyst. The catalyst also exhibited excellent nickel and vanadium passivation performance, strong bottoms upgrading selectivity, and better gasoline and coke selectivity. In comparison to the reference catalyst, the yields of the gasoline and light oil increased by 1.61 and 1.31 percentage points, respectively, and the coke yield decreased by 0.22 percentage points, and the olefin content in the produced gasoline reduced by 2.51 percentage points, with the research octane number increased by 0.7 unit.
基金support provided by the National Natural Science Foundation of China(Granted No.21276276)
文摘The Mo modified Ni/Al_2O_3 catalysts were prepared and sulfided at different temperatures, and their catalytic activity for thioetherification of mercaptans and olefins(or dienes), hydrogenation of dienes and olefins in the thioetherification process using fluidized catalytic cracking(FCC) naphtha as the feedstock was investigated. In order to disclose the correlation between the physicochemical characteristics of catalysts and their catalytic activity, the surface structures and properties of the catalysts sulfided at different temperatures were characterized by the high resolution transmission electronic microscopy(HRTEM), X-ray photoelectron spectroscopy(XPS) and H2-temperature programmed reduction(H_2-TPR) technique. The results showed that an increase of sulfurization temperature not only could promote the sulfurization degree of active metals on the catalysts, but also could adjust the micro-morphology of active species. These changes could improve the catalytic performance of thioetherification, and hydrogenation of dienes and olefins. However, an excess sulfurization temperature was more easily to upgrade the ability of the catalyst for hydrogenation of olefins, which could lead to a decrease of the octane number of the product. It was also showed that a moderate sulfurization temperature not only could improve the catalytic performance of thioetherification and hydrogenation of dienes but also could control hydrogenation of olefins.
基金Funded by the National Natural Science Foundation of China(No.51204125)the Natural Science Foundation of Hubei Province(Nos.2014CFB812 and 2014CFB810)the Open Fund Project Funded by the Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province in China(No.WKDM201302)
文摘A new carbon bridged cyclopentadienyl chromium complex of the type [（C5H4）C（CH3）2 CH2（C5H4N）]CrCl2 was prepared by treatment of CrCl3·（THF）3 in THF solution with the lithium salt of ligand containing cyclopentadienyl and pyridyl groups. The chromium complex was characterized by 1H NMR and elemental analysis（EA）, and the crystal structure was determined by X-ray diffraction analysis. Activated by Al（i-Bu）3, the chromium complex displayed a very high activity for methyl methacrylate（MMA） polymerization. After 24 hours,more than 95.5% MMA was converted to polymethyl methacrylate（PMMA） with a viscosity average molecular weight（Wη） of 416000 g·mol-1 at 60 ℃ for MMA/ Al（i-Bu）3 /chromium catalyst molar ratio of up to 2000：20：1. Effects of temperature, molar ratios of MMA/catalyst and catalyst/cocatalyst on the polymerization have been studied. The high conversion of MMA and high molecular weight of PMMA with narrow molecular weight distribution is caused by the unique stable active site formed by the new chromium complex and aluminum cocatalyst.
基金supported by the National Natural Science Foundation of China(21771083)the Basic Advancing Front Project of Jilin University.
文摘Single-atom dispersed carbon nitride photocatalysts have been extensively associated with clean energy conversion,storage and utilization.However,it is still a challenge to elucidate the relationship between the electronic structure of catalysts and their photocatalytic properties.In this work,single atom Ag/C_(3)N_(4)catalysts have been prepared via pyrolyzing cyanuric acid,AgNO_(3)and melamine as precursors.We observe that their photocatalytic activity increases on increasing the concentration of Ag from 0.32%to 0.53%,and subsequently decreases on further increasing the concentration of Ag,which indicates that the concentration of Ag atoms can control the performance of single-atom catalysts.Deep investigations suggest that the concentration of Ag atoms can modulate the bottom of the conduction band(CB)and the maximum of the valence band(VB).The higher the bottom of the CB is,the better the performance of catalysts is.In contrast to bulk carbon nitride,the rate constants of the optimized single-atom photocatalyst Ag/C_(3)N_(4)with 0.53%Ag for rhodamine B(RhB)and tetracycline(TC)degradation are enhanced approximately 165.3 and 24.9 times,respectively.Furthermore,the ESR spectrum shows that the superoxide radical plays a major role in the photocatalytic process.This work provides a new insight into the structure–property relationship and our strategy provides guidance for the synthesis of other single-atom photocatalysts.
基金sponsored by the National Natural Science Foundation of China(No.12175145)the Shanghai Rising-Star Program(No.24YF2729800)。
文摘Residual ions introduced during catalyst synthesis can significantly impact both the structure and performance of the catalyst.Despite their crucial role,the effects of these residual ions are frequently overlooked in catalyst design and optimization.This review systematically surveys the characteristics and sources of typical residual ions in catalytic systems,including halogen anions,acidic anions,and alkali metal cations.It also examines their impact on both the supports and active metals of supported catalysts,as well as the alterations in surface,crystal structure,and chemical states of non-supported catalysts.The effects of residual ions on the performance of these catalysts in catalytic reactions such as oxidation and hydrogenation are discussed in detail.Additionally,the influence mechanism of residual ions on the catalysts is further explored,with a focus on their promotion and inhibition roles in catalytic processes,thus providing insights for the development of more efficient and durable catalysts.A summary finally provides an outlook on future approaches to advance catalyst preparation and mitigate the adverse effects of residual ions in catalysis.
文摘The effects of reaction solvent, the properties of Sb 4O 5Cl 2 material and the ligand additives on the reaction rate and polymorph of antimony white(Sb 2O 3) in the reaction of Sb 4O 5Cl 2 transforming into Sb 2O 3 have been investigated by XRD and IR method. It is revealed that the reaction solvent and the properties of Sb 4O 5Cl 2 are the key factors affecting the reaction rate. The polymorph of antimony trioxides is determined by the reaction mechanism, i.e. the coordination state of the antimony activated complex. Adding a little ligand such as EDTA is the most economical and effective method of synthesizing cubic antimony white(Sb 2O 3)in hydrometallurgical transformation process.
基金Supported by the Ministry of Education of China(No.208066)the Education Department of Fujian Province(JA07029)the State Key Laboratory of Structural Chemistry(No.20130013)
文摘The title complex bis{4-chloro-2-[（6-methyl-pyridin-2-ylimino）-methyl]-phenol}-palladium（Ⅱ）（C_（26）H_（20）Cl_2N_4O_2Pd） has been synthesized by the reaction of 4-chloro-2-[（6-methylpyridin- 2-ylimino）-methyl]-phenol with Pd（CH_3COO）_2, and characterized by IR spectrum and elemental analysis. Single-crystal X-ray diffraction analysis results further confirmed the molecular structures. The crystal belongs to the monoclinic system, space group P2_1/c with a = 4.1324（2）, b = 23.5432（16）, c = 11.8943（8） A, β = 91.238（5）o, V = 1156.93（12） ？~3, C_（26）H_（20）Cl_2N_4O_2Pd, M_r = 597.76, Z = 2, D_c = 1.716 g/cm^3, μ = 1.067 mm^（-1）, F（000） = 600, the final R = 0.0247 and w R = 0.0677（I 〉 2σ（I））. In the presence of methylaluminoxane（MAO）, the complex exhibits excellent catalytic activities（1.737×10~7 g of PNB（mol of Pd）^（-1）·h^（-1）） in the vinyl polymerization of norbornene.
基金Supported by the Natural Science Foundation of Fujian Province(2010J01026)the Ministry of Education of China(No.208066)+1 种基金the Education Department of Fujian Province(JA07029)the State Key Laboratory of Structural Chemistry(No.20130013)
文摘The title complex bis{1-{[（6-ethyl-2-pyridinyl）imino]methylenyl}-2-naphthale- nolato-N,O}-nickel（lI） （C36H32NnO2Ni） has been synthesized by the reaction of l-{[（6-ethyl-2- pyridinyl）imino]methylenyl}-2-naphthalenol with Ni（CH3COO）2·4H2O, and characterized by IR spectrum, elemental analysis and TG. The complicated space structure has been confirmed by single-crystal X-ray diffraction analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 11.410（4）, b = 14.382（4）, c = 18.121（6） ,A, β = 97.147（6）% V= 2950.5（16）A3, C36H32N4O2Ni, Mr = 611.37, Z = 4, Dc = 1.376 g/cm3, μ = 0.698 mm-1 F（000） = 1280, the final R = 0.0519 and wR = 0.1493 （1 〉2σ（I））. This title compound was used as precatalysts for the polymerisation of norbornene. When activated with MAO, the complex exhibited excellent catalytic activity up to 1.98 × 107 g ofPNB （mol of Ni）-1 h-1 with high monomer conversion.
