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Regeneration of Spent Catalyst and Impregnation of Catalyst by Supercritical Fluid
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作者 Farid M. Gumerov Bernard Le Neindre +1 位作者 Timur R. Bilalov Ajrat A. Sagdeev 《International Journal of Analytical Mass Spectrometry and Chromatography》 2016年第4期51-65,共16页
The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The an... The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The analysis of deactivating compounds has been carried out for industrial catalysts such as: 1) palladium catalyst G-58E of ethane-ethylene fraction hydrogenation;2) nickel/kieselguhr catalyst of process of separating acetylenic compounds from isoprene;3) active aluminum oxide catalyst of methyl phenyl carbinol dehydration process;4) palladium catalyst LD-265 of hydrocarbons hydrogenation process;5) nickel-molybdenum catalysts DN-3531 and Criterion 514 of kerosene hydrotreating process. The results of the study of catalyst deactivating compounds solubility in pure supercritical carbon dioxide and supercritical carbon dioxide are modified with polar additive. The results of the solubility study are described using the Peng-Robinson equation of state. The results of the implementation of the supercritical fluid СО<sub>2</sub> extraction process with respect to deactivated industrial catalyst samples have been provided. A comparison of the characteristics of samples of catalysts regenerated using the traditional approach and the SC-CO<sub>2</sub> extraction process has been conducted. The possibility of using supercritical fluid CO<sub>2</sub> impregnation process in the synthesis of a palladium catalyst has been investigated. The synthesis of palladium chloride-based organometallic complexes has been carried out. The results of the study of solubility thereof in supercritical carbon dioxide have been provided. A dynamic supercritical fluid CO<sub>2</sub> impregnation process condition has been implemented. A comparison of the characteristics of palladium catalyst samples synthesized using the conventional approach and SC-CO<sub>2</sub> impregnation process has been conducted and presented in the book. 展开更多
关键词 Palladium catalyst G-58E Nickel/Kieselguhr/Diatomite catalyst Active Aluminum Oxide catalyst Palladium catalyst LD-265 Nickel-Molybdenum catalysts DN-3531 and Criterion 514 catalyst Regeneration catalyst Activity Benzonitrile Complex of Palladium Chloride Styrene Complex of Palladium Chloride Cyclohexene Complex of Palladium Chloride
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SYNTHESIS AND APPLICATIONS OF CROSS-LINKED POLY(DIALLYLDIMETHYL AMMONIUM CHLORIDE) AND ITS DERIVATIVE COPOLYMERS AS EFFICIENT PHASE TRANSFER CATALYST FOR NUCLEOPHILIC SUBSTITUTION REACTIONS 被引量:11
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作者 Hossein Mahdavi Mahdi Mahmoudian 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2011年第2期165-172,共8页
Cross-linked poly(diallyldimethylammonium chloride) and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange reactions.... Cross-linked poly(diallyldimethylammonium chloride) and its derivative copolymers were synthesized and used as phase transfer catalyst in the nucleophilic substitution reaction especially halogen exchange reactions.In addition,the effect of hydrophilic-hydrophobic character of the polymers in the nucleophilic reactions was investigated. 展开更多
关键词 Poly(diallyldimethylammonium chloride) Phase transfer catalyst Nucleophilic substitution reaction Halogen exchange reaction
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β-Cyclodextrin Immobilized onto Dowex Resin: A Unique Microvessel and Heterogeneous Catalyst in Nucleophilic Substitution Reactions 被引量:5
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作者 Kiasat, Ali Reza Zarinderakht, Nasrollah Sayyahi, Soheil 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第3期699-702,共4页
The catalytic activity ofβ-cyclodextrin immobilized on Dowex resin as an efficient solid-liquid phase transfer catalyst was developed for the synthesis of alkyl thiocyanates and phenacyl derivatives in water. The nuc... The catalytic activity ofβ-cyclodextrin immobilized on Dowex resin as an efficient solid-liquid phase transfer catalyst was developed for the synthesis of alkyl thiocyanates and phenacyl derivatives in water. The nucleophilic substitution reactions were performed under mild reaction condition and gave the products in excellent yields. Fur thermore, the catalyst could be recycled by facile separation without any loss of activity. 展开更多
关键词 heterogeneous catalyst β-cyclodextrin immobilization nucleophilic substitution alkyl thiocyanate phenacyl derivatives
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Substitution reaction of dicyandiamide in the presence of phase transfer catalyst
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作者 周景尧 姚旭波 +1 位作者 贾瑜 李妙葵 《Chinese Science Bulletin》 SCIE EI CAS 1996年第15期1263-1265,共3页
Dicyandiamide (cyanoguanidine) is widely used in the syntheses of melamine and medicines such as barbiturates and guanidine derivatives. However, the substitution reaction of dicyandiamide, particularly the tetra subs... Dicyandiamide (cyanoguanidine) is widely used in the syntheses of melamine and medicines such as barbiturates and guanidine derivatives. However, the substitution reaction of dicyandiamide, particularly the tetra substitution reaction, has not been reported so far. We report here the substitution reaction of dicyandiamide in the presence of phase transfer catalyst. 展开更多
关键词 DICYANDIAMIDE substitution REACTION PHASE TRANSFER catalyst.
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SILICA-BOUND CROWN ETHERS PLATINUM COMPLEX AS HYDROSILYLATION CATALYST
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作者 陈远荫 孟令芝 +2 位作者 李立平 罗介奇 胡缙昌 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第1期22-25,共4页
Silica-bound 15-Crown-5, 18-Crown-6 with a spacer of propyloxymethyl and their platinum complexes have been synthesized. It was found that they were efficient catalysts for the hydrosilylation of olefms with triethoxy... Silica-bound 15-Crown-5, 18-Crown-6 with a spacer of propyloxymethyl and their platinum complexes have been synthesized. It was found that they were efficient catalysts for the hydrosilylation of olefms with triethoxysilane in the temperature range of 60 to 130 ℃. 展开更多
关键词 Crown ether Supported crown ether Platinum complex Hydrosilylation catalyst Supported catalyst.
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An Experimental Study of the Performance of Isomorphically Zirconium-Substituted Mesoporous Alumina Supported Cobalt Catalysts in Fischer-Tropsch Synthesis
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作者 Sabar Simanungkalit Mingming Zhu +2 位作者 Gia Hung Pham Zhezi Zhang Dongke Zhang 《Advances in Chemical Engineering and Science》 2022年第1期40-53,共14页
A series of mesoporous alumina (MA) supported cobalt (Co/MA) catalysts with MA isomorphically substituted by zirconium (Zr) were synthesised and evaluated for their performance in the Fischer</span><span styl... A series of mesoporous alumina (MA) supported cobalt (Co/MA) catalysts with MA isomorphically substituted by zirconium (Zr) were synthesised and evaluated for their performance in the Fischer</span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;">Tropsch synthesis. The Zr/(Zr + Al) atomic ratios varied from 1% - 15%. A zirconium-impregnated Co/MA catalyst prepared by wet impregnation with a Zr/(Zr + Al) atomic ratio of 5% was also evaluated to examine Zr incorporation’s effect method. The catalysts synthesised were characterised using N</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> adsorption-desorption, X-ray Powder Diffraction (XRD), Transmission Electron Microscopy (TEM), and X-Ray Photoelectron Spectroscopy (XPS). It was found that Zr</span><sup><span style="font-family:Verdana;">4+</span></sup><span style="font-family:Verdana;"> ions were incorporated into the framework of MA and kept intact up to a Zr/(Zr + Al) atomic ratio of 5%. The cobalt dispersion and reducibility were improved as the Zr/(Zr + Al) atomic ratio increased to 50%. The performance of these catalysts for Fischer</span></span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;">Tropsch synthesis was evaluated using a fixed bed reactor at temperature and pressure of 493 K and 20 bar, respectively. The feed syngas </span><span><span style="font-family:Verdana;">had an H</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">/CO ratio of 2, diluted with 10% Ar. For isomorphically</span></span><span style="font-family:Verdana;"> Zr-substituted Co/MA, the CO conversion and selectivity of diesel (C</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> - C</span><sub><span style="font-family:Verdana;">20</span></sub><span style="font-family:Verdana;">) increased first and then decreased with increasing the Zr/(Zr + Al) atomic ratio. The maximum 38.9% CO conversion and 34.6% diesel (C</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> - C</span><sub><span style="font-family:Verdana;">20</span></sub><span style="font-family:Verdana;">) selectivity were obtained at Zr/(Zr + Al) atomic ratio of 5%. The isomorphic substitution method was better than the wet impregnation method in CO conversion and diesel selectivity. 展开更多
关键词 Cobalt catalyst Fischer-Tropsch Synthesis Isomorphic substitution Mesoporous Alumina ZIRCONIUM
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Preparation of Ultrafine and High Dispersion Pd/C Catalyst and Its Electrocatalytic Performance for Formic Acid Oxidation 被引量:8
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作者 TANG Ya-wen ZHANG Lin-lin +4 位作者 WANG Xin BAO Jian-chun ZHOU Yi-ming LU Lu-de LU Tian-hong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第2期239-242,共4页
A carbon supported Pd(Pd/C) catalyst used as the anodic catalyst in the direct formic acid fuel cells(DFAFC) was prepared via the improved complex reduction method with sodium ethylenediamine tetracetate(EDTA) a... A carbon supported Pd(Pd/C) catalyst used as the anodic catalyst in the direct formic acid fuel cells(DFAFC) was prepared via the improved complex reduction method with sodium ethylenediamine tetracetate(EDTA) as stabilizer and complexing agent. This method is very simple. The average size of the Pd particles in the Pd/C catalyst prepared with the improved complex reduction method is as small as about 2.1 nm and the Pd particles in the Pd/C catalyst possess an excellent uniformity. The Pd/C catalyst shows a high electrocatalytic activity and stability for the formic acid oxidation. 展开更多
关键词 Pd/C catalyst Complex reduction method Formic acid oxidation
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Chitosan-immobilized Palladium Complex: a Green and Highly Active Heterogeneous Catalyst for Heck Reaction 被引量:4
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作者 PuLIU LanWANG XiangYuWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第4期475-477,共3页
A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared. The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions. The catalyst can ... A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared. The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions. The catalyst can be separated easily from the reaction mixture and reused after washing. Under the suitable reaction conditions, the cross-coupling of iodobenzene (ArI) with acrylic acid (AA) or acrylate can be achieved 93.3% or 99% yield of trans-cinnamic acid or trans-cinnamic ester. 展开更多
关键词 Chitosan-immobilized palladium complex green catalyst Heck reaction.
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Characterization and performance of Cu/ZnO/Al_2O_3 catalysts prepared via decomposition of M(Cu,Zn)-ammonia complexes under sub-atmospheric pressure for methanol synthesis from H_2 and CO_2 被引量:7
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作者 Danjun Wang Jun Zhao +1 位作者 Huanling Song Lingjun Chou 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第6期629-634,共6页
Methanol synthesis from hydrogenation of CO2 is investigated over Cu/ZnO/Al2O3 catalysts prepared by decomposition of M(Cu,Zn)-ammonia complexes (DMAC) at various temperatures.The catalysts were characterized in d... Methanol synthesis from hydrogenation of CO2 is investigated over Cu/ZnO/Al2O3 catalysts prepared by decomposition of M(Cu,Zn)-ammonia complexes (DMAC) at various temperatures.The catalysts were characterized in detail,including X-ray diffraction,N2 adsorption-desorption,N2O chemisorption,temperature-programmed reduction and evolved gas analyses.The influences of DMAC temperature,reaction temperature and specific Cu surface area on catalytic performance are investigated.It is considered that the aurichalcite phase in the precursor plays a key role in improving the physiochemical properties and activities of the final catalysts.The catalyst from rich-aurichalcite precursor exhibits large specific Cu surface area and high space time yield of methanol (212 g/(Lcat·h);T=513 K,p=3MPa,SV=12000 h-1). 展开更多
关键词 decomposition of M(Cu Zn)-ammonia complexes Cu/ZnO/Al2O3 catalyst CO2 hydrogenation methanol synthesis
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Selective Oxidation of Isobutylene over Cs-promoted Mo-Bi-Co-Fe-Ce-O Catalyst 被引量:4
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作者 王蕾 李增喜 +2 位作者 张锁江 张香平 赵威 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期705-708,共4页
Cs-promoted Mo-Bi-Co-Fe-Ce-O catalyst for the selective oxidation of isobutylene to methacrolein had been studied in a fixed bed micro-reactor. The selectivity to methacrolein was significantly improved by the additio... Cs-promoted Mo-Bi-Co-Fe-Ce-O catalyst for the selective oxidation of isobutylene to methacrolein had been studied in a fixed bed micro-reactor. The selectivity to methacrolein was significantly improved by the addition of Cs, which could probably enhance the dehydrogenation ability and weaken the oxygenation ability of the catalyst based on temperature programmed reduction (TPR) analysis investigation. The kinetic studies indicated that the oxidation of isobutylene to methacrolein followed the first-order kinetic behavior. 展开更多
关键词 ISOBUTYLENE selective oxidation complex catalyst KINETICS
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Dehydrogenation characteristics of LiAlH4 improved by in-situ formed catalysts 被引量:2
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作者 Jiaxing Cai Lei Zang +2 位作者 Lipeng Zhao Jian Liu Yijing Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第5期868-873,共6页
The hydrogen storage properties and catalytic mechanism of FeCl-doped LiAlHwere investigated in minute details. LiAlH-2 mol% FeClsamples start to release hydrogen at 76 °C, which is 64 °C lower than that of ... The hydrogen storage properties and catalytic mechanism of FeCl-doped LiAlHwere investigated in minute details. LiAlH-2 mol% FeClsamples start to release hydrogen at 76 °C, which is 64 °C lower than that of as-received LiAlH. Isothermal desorption measurements show that the 2 mol% FeCl-doped sample releases 7.0 wt% of hydrogen within 17 min at 250 °C. At lower temperatures of 110 °C and 80 °C, the sample can release 4.4 wt% and 3 wt% of hydrogen, respectively. The apparent activation energy of LiAlH-2 mol% FeClsamples for R2 is 105.02 k J/mol, which is 67 k J/mol lower than that of pure LiAlH. The reaction between LiAlHand FeClduring ball milling was found by analyzing the X-ray diffraction results,and Fe-Al particles formed in-situ from the reaction act as the real catalyst for the dehydrogenation of LiAlH. 展开更多
关键词 Hydrogen storage materials DEHYDROGENATION Complex hydrides LiAlH4 FeCl2 doping In-situ formed catalysts
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Preparation of Nano-Sized γ-Al_2O_3 Supported Iron Catalyst for Fischer-Tropsch Synthesis by Solvated Metal Atom Impregnation Methods 被引量:2
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作者 Lihua Yu Xiaoxiang Zhang Zongjie Du Da Wang Shurong Wang Shihua Wu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第1期46-52,共7页
Two types of small iron clusters supported on γ-Al2O3-RT(dehydroxylated at room temperature) and γ-Al2O3-800 (dehydroxylated at 800 ℃) were prepared by solvated metal atom impregnation (SMAI) techniques. The ... Two types of small iron clusters supported on γ-Al2O3-RT(dehydroxylated at room temperature) and γ-Al2O3-800 (dehydroxylated at 800 ℃) were prepared by solvated metal atom impregnation (SMAI) techniques. The iron atom precursor complex, bis(toluene)iron(0) formed in the metal atom reactor, was impregnated into γ-Al2O3 having different concentrations of surface hydroxyl groups to study the effect of surface hydroxylation on the crucial stage of iron cluster formation. Catalysts prepared in this way were characterized by TEM, Mǒssbauer, and chemisorption measurements, and the results show that higher concentration of surface hydroxyl groups of γ-Al2O3-RT favors the formation of more positively charged supported iron cluster Fen/γ-Al2O3-RT, and the lower concentration of surface hydroxyl groups of γ-Al2O3-800 favors the formation of basically neutral supported iron cluster Fen/γ-Al2O3-800. The measured results also indicate that the higher concentration of surface hydroxyl groups causes the rapid decomposition of precursor complex, bis(toluene)iron(0), and favors the formation of relatively large iron cluster. Consequently, these two types of catalysts show different catalytic properties in Fischer-Tropsch reaction. The catalytic pattern of Fen/γ-Al2O3-RT in F-T reaction is similar to that of the unreduced γ-Fe2O3 and that of Fen/γ-Al2O3-800 is similar to that of the reduced α-Fe2O3. 展开更多
关键词 iron clusters solvated metal atom impregnation iron atom precursor complex FischerTropsch synthesis alumina supported catalyst
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Highly Active New α-Diimine Nickel Catalyst for Polymerization of Ethylene 被引量:2
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作者 YUAN Jian-chao LIU Yu-feng MEI Tong-jian WANG Xue-hu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第6期1014-1018,共5页
A new α-diimine ligand 1a, bis[N,N′-(4-tert-butyl-2,6-dimethylphenyl)imino]-2,3-butanediylidene and its corresponding Ni(II) complex 2a, {bis[N,N′-(4-tert-butyl-2,6-dimethylphenyl)imino]-2,3-butanediylidene}d... A new α-diimine ligand 1a, bis[N,N′-(4-tert-butyl-2,6-dimethylphenyl)imino]-2,3-butanediylidene and its corresponding Ni(II) complex 2a, {bis[N,N′-(4-tert-butyl-2,6-dimethylphenyl)imino]-2,3-butanediylidene}dibromo- nickel were successfully synthesized, and characterized by 1H NMR, 13C NMR, Fourier transform infrared spectroscope(FTIR), elemental analysis and X-ray photoelectron spectroscopy(XPS). α-Diimine ligand 1b, bis[N,N′-(2,6- dimethylphenyl)imino]-2,3-butanediylidene and its corresponding Ni(II) complex 2b, {bis[N,N′-(2,6-dimethyl- phenyl)imino]-2,3-butanediylidene}dibromonickel were also synthesized and characterized for comparison. The pre-catalyst 2a with sterically bulky, electron-donating group tert-butyl, activated by diethylaluminum chloride (DEAC) and tested in the polymerization of ethylene, was very highly active[2.01×107 g PE/(mol Ni?h?0.1 MPa)] and led to a very highly branched polyethylene(ca. 35―103 branches/1000 C). The state of the polyethylene obtained varied from plastic, elastomer polymers to the oil-like hyperbranched polymers. 展开更多
关键词 a-Diimine nickel(II) complex Diethylaluminium chloride Late transition metal catalyst Ethylene poly-merization
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Direct conversion of corn cob to formic and acetic acids over nano oxide catalysts 被引量:1
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作者 Liyuan Cheng Hong Liu +2 位作者 Yuming Cui Nianhua Xue Weiping Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第1期43-49,共7页
Considering energy shortage, large molecules in corn cob and easy separation of solid catalysts, nano oxides are used to transform corn cob into useful chemicals. Because of the microcrystals, nano oxides offer enough... Considering energy shortage, large molecules in corn cob and easy separation of solid catalysts, nano oxides are used to transform corn cob into useful chemicals. Because of the microcrystals, nano oxides offer enough accessible sites for cellulose, hemicellulose and monosaccharide from corn cob hydrolysis and oxidant. Chemical conversion of corn cob to organic acids is investigated over nano ceria, alumina, titania and zirconia under various atmospheres. Liquid products are mainly formic and acetic acids. A small amount of other compounds, such as D-xylose,D-glucose, arabinose and xylitol are also detected simultaneously. The yield of organic acids reaches 25%–29% over the nano oxide of ceria,zirconia and alumina with 3 h reaction time under 453 K and 1.2 MPa O2. The unique and fast conversion of corn cob is directly approached over the nano oxides. The results are comparative to those of biofermentation and offer an alternative method in chemically catalytic conversion of corn cob to useful chemicals in a one-pot chemical process. 展开更多
关键词 Acetic acid ALUMINA catalystS CELLULOSE Organic acids Sugar substitutes
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Synthesis of Pt and Pt-Fe nanoparticles supported on MWCNTs used as electrocatalysts in the methanol oxidation reaction 被引量:1
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作者 J.R.Rodriguez R.M.Félix +4 位作者 E.A.Reynoso Y.Gochi-Ponce Y.Verde Gómez S.Fuentes Moyado G.Alonso-Núez 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第4期483-490,共8页
This work reports a feasible synthesis of highly-dispersed Pt and Pt-Fe nanoparticles supported on multiwall carbon nanotubes (MWCNTs) without Fe and multiwall carbon nanotubes with iron (MWCNTs-Fe) which applied ... This work reports a feasible synthesis of highly-dispersed Pt and Pt-Fe nanoparticles supported on multiwall carbon nanotubes (MWCNTs) without Fe and multiwall carbon nanotubes with iron (MWCNTs-Fe) which applied as electrocatalysts for methanol electrooxidation. A Pt coordination complex salt was synthesized in an aqueous solution and it was used as precursor to prepare Pt/MWCNTs, Pt/MWCNTs-Fe, and Pt-Fe/MWCNTs using FeC12.4H20 as iron source which were named S 1, S2 and S3, respectively. The coordination complex of platinum (TOA)2PtC16 was obtained by the chemical reaction between (NH4)2PtC16 with tetraoctylammonium bromide (TOAB) and it was characterized by FT-IR and TGA. The materials were characterized by Raman spectroscopy, SEM, EDS, XRD, TEM and TGA. The electrocatalytic activity of Pt-based supported on MWCNTs in the methanol oxidation was investigated by cyclic voltammetry (CV) and chronoamperometry (CA). Pt-Fe/MWCNTs electrocatalysts showed the highest electrocatalytic activity and stability among the tested electrocatalysts due to that the addition of "Fe" promotes the OH species adsorption on the electrocatalyst surface at low potentials, thus, enhancing the activity toward the methanol oxidation reaction (MOR). 展开更多
关键词 coordination complex salt MWCNTS nanoparticles catalystS ELECTROOXIDATION
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Study on Polymerization of 4-Vinylpyridine by Neodymium Complex Catalyst 被引量:1
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作者 王晓菊 陈瑞战 曲雅焕 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第2期155-157,共3页
Polymerization of 4-vinylpyridine by complex catalyst of neodymium chloride was studied. The influence of Al/Nd (molar ratio), concentration of catalyst, reaction time and temperature on polymerization of 4-vinylpyrid... Polymerization of 4-vinylpyridine by complex catalyst of neodymium chloride was studied. The influence of Al/Nd (molar ratio), concentration of catalyst, reaction time and temperature on polymerization of 4-vinylpyridine was investigated. The results show that different kinds of ligand in the rare earth complex have an effect on the catalytic activity of the complex. The catalytic activity of the rare earth complex is higher than that of simple rare earth chloride. The catalytic activity of polymer-supported catalyst is higher than those of the similar small molecular system. 展开更多
关键词 rare earths 4-VINYLPYRIDINE neodymium complex catalyst POLYMERIZATION
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Co-salen functionalized on graphene as an efficient heterogeneous catalyst for cyclohexene oxidation 被引量:1
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作者 Jing Sun Jian Zhang +3 位作者 Liang Wang Longfeng Zhu Xiangju Meng Feng-Shou Xiao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第1期48-51,共4页
Co-salen functionalized on graphene with an average pore size of 27.7 nm as a heterogeneous catalyst exhibited good catalytic activity and recyclability in cyclohexene oxidation.
关键词 heterogeneous catalyst GRAPHENE cyclohexene oxidation porous materials Co-salen complex
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Ammoxidation of Substituted Toluenes on Silica-Supported VPO Catalysts 被引量:1
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作者 Xie Guang\|yong, Zheng Qiong , Huang Chi, Li Xiao\|yun, Yu Peng, Chen Yuan\|yin College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期356-360,共5页
The ammoxidation of substituted toluenes to their corresponding nitriles over silica-supported vanadium phosphorus oxide (VPO/SiO2) catalysts has been studied. the effects of carrier silica, the addition of phosphorus... The ammoxidation of substituted toluenes to their corresponding nitriles over silica-supported vanadium phosphorus oxide (VPO/SiO2) catalysts has been studied. the effects of carrier silica, the addition of phosphorus, the substituents and the loadings have been discussed. Compared with unsupported VPO, the VPO/SiO2 catalysts have higher catalytic activity for ammoxidation of substituted toluenes and much lower reaction temperature. XRD shows that vanadium phosphorus oxides exist as amorphous phase and disperse to a high degree on the silica surface in 10%loading catalyst. When the loadings are over 10%, the crystalline α-VOPO4 would emerge, which would decrease the yield and selectivity. Additional phosphorus can form composite oxides with vanadia and play concerted catalytic function, which increase the selectivity of nitriles remarkably. Different substituents or same substituents on different positions have different influences because of the variant electronic stability of intermediates, the hindered accessibility of methyl group or the chemisorption state of the substrate molecule on the electrophilic catalyst surface. 展开更多
关键词 AMMOXIDATION VPO/SiO2 catalyst substituted toluenes aromatic nitriles
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A Sterically Hindered Zirconocene Complex (1,2-Ph_2C_5H_3)_2ZrCl_2:Synthesis,Structure and Properties as Olefin Polymerization Catalyst 被引量:1
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作者 Fan ZHANG Ying MU +3 位作者 Yue Tao ZHANG Cong Xi CHEN Hui Min ZHAI Han HONG(Department of Chemistry, Jilin University, Changchun 130023Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第7期641-644,共4页
An unbridged zirconocene complex bis(1,2-diphenylcyclopentadienyl)zirconium dichloride [(1,2-Ph2-C5H3)2ZrCl2] 1 has been synthesized and structurally characterized. When activated by MAO, 1 produces ultra-high molecul... An unbridged zirconocene complex bis(1,2-diphenylcyclopentadienyl)zirconium dichloride [(1,2-Ph2-C5H3)2ZrCl2] 1 has been synthesized and structurally characterized. When activated by MAO, 1 produces ultra-high molecular weight polyethylene with high melting transition temperature, as well as atactic oligopropylene with average molecular weight of ~1150 g mol-1. 展开更多
关键词 Zirconium complex metallocene catalyst olefin polymerization
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Polymerization of Styrene and 1,3-Butadiene by Catalyst Systems Based on Calix[4]arene Neodymium Complexes 被引量:1
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作者 Yan Song ZHENG Zhi Quan SHEN(Department of Chemistry, Huazhong University of Science and Technology wuhan 430074)(Institute of Polymer Sciences and Materials, Zhejiang University Hangzhou 310027) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第7期597-600,共4页
Polymerization of styrene and 1,3-butadiene were performed by calix[4]arene-neodymium complexes using di-n-butylmagnesium and tri-iso-butylaluminum as cocatalyst respectively. The effect of the substituent groups in c... Polymerization of styrene and 1,3-butadiene were performed by calix[4]arene-neodymium complexes using di-n-butylmagnesium and tri-iso-butylaluminum as cocatalyst respectively. The effect of the substituent groups in calix[4]arene on the catalytic activity was first investigated. 展开更多
关键词 arene-neodymium complexes POLYMERIZATION catalyst
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