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Self-regeneration of activated carbon modified with palladium catalyst for electrochemical dechlorination 被引量:1
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作者 Yan Qing Cong Zu Cheng Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期1013-1016,共4页
Catalyst regeneration and the retention of high catalytic activity are still the critical issues in environmental application. A novel fluidized gas-liquid-solid electrochemical reactor was developed to simultaneously... Catalyst regeneration and the retention of high catalytic activity are still the critical issues in environmental application. A novel fluidized gas-liquid-solid electrochemical reactor was developed to simultaneously remove chlorinated pollutants and in situ regenerate the spent catalyst. Activated carbon modified with palladium catalyst (AC-Pd) was prepared for electrochemical dechlorination. For the 4-chlorophenol wastewater of initial concentration 200 mg· L^- 1, the removal efficiency could nearly reach 100% in less than 30 rain. Catalytic activity of AC-Pd catalyst was preserved effectively even in consecutive cycling run without special regeneration. OH radicals, generated by electrochemical reaction, played a critical role in self-regeneration of AC-Pd. High catalytic activity of spent AC-Pd catalyst provided an attractive alternative in wastewater treatment. 展开更多
关键词 activated carbon palladium Electrochemical dechlorination Hydroxyl radical REGENERATION
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Highly reactive and reusable heterogeneous activated carbons-based palladium catalysts for Suzuki-Miyaura reaction
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作者 Yifan Jiang Bingqi Xie Jisong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期165-172,共8页
Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch ... Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode.This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heterogeneous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and durability in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports. 展开更多
关键词 Suzuki-Miyaura reaction Heterogeneous palladium catalysts activated carbon Thiol-and amino-functionalization catalyst support Packed bed
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Highly active catalyst for vinyl acetate synthesis by modified activated carbon 被引量:5
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作者 Chun Yan Hou Liang Rong Feng Fa Li Qiu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第7期865-868,共4页
A new zinc acetate catalyst which was prepared from modified activated carbon exhibited extreme activity towards the synthesis of vinyl acetate. The activated carbon was modified by nitric acid, vitriol and peroxyacet... A new zinc acetate catalyst which was prepared from modified activated carbon exhibited extreme activity towards the synthesis of vinyl acetate. The activated carbon was modified by nitric acid, vitriol and peroxyacetic acid (PAA). The effect on specific area, structure, pH and surface acidity groups of carders by modification was discussed. Amount of carbonyl and carboxyl groups in activated carbon was increased by peroxyacetic acid treatment. The productivity of the new catalyst was 14.58% higher than that of catalyst prepared using untreated activated carbon. The relationship between amount of carbonyl and carboxyl groups (m) and catalyst productivity (P) was P = 1.83 + 2.26 × 10^-3*e^3.17m. Reaction mechanism was proposed. C 2009 Liang Rong Feng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Surface acidic groups Peroxyacetic acid activated carbon catalyst for vinyl acetate synthesis
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Effect of Activated Carbon as a Support on Metal Dispersion and Activity ofRuthenium Catalyst for Ammonia Synthesis 被引量:3
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作者 ZHENG Xiao-ling ZHANG Shu-juan +3 位作者 LIN Jian-xin XU Jiao-xing FU Wu-jun WEI Ke-mei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第4期448-452,共5页
Ten kinds of activated carbon from different raw materials were used as supports to prepare ruthenium catalysts. N_2 physisorption and CO chemisorption were carried out to investigate the pore size distribution and th... Ten kinds of activated carbon from different raw materials were used as supports to prepare ruthenium catalysts. N_2 physisorption and CO chemisorption were carried out to investigate the pore size distribution and the ruthenium dispersion of the catalysts. It was found that the Ru dispersion of the catalyst was closely related to not only the texture of carbon support but also the purity of activated carbon. The activities of a series of the carbon-supported barium-promoted Ru catalysts for ammonia synthesis were measured at 425 ℃, 10 0 MPa and 10 000 h -1. The result shows that the same raw material activated carbon, with a high purity, high surface area, large pore volume and reasonable pore size distribution might disperse ruthenium and promoter sufficiently, which activated carbon as support, could be used to manufacture ruthenium catalyst with a high activity for ammonia synthesis. The different raw material activated carbon as the support would greatly influence the catalytic properties of the ruthenium catalyst for ammonia synthesis. For example, with coconut shell carbon(AC1) as the support, the ammonia concentration in the effluent was 13 17% over 4%Ru-BaO/AC1 catalyst, while with the desulfurized coal carbon(AC10) as the support, that in the effluent was only 1 37% over 4%Ru-BaO/AC10 catalyst. 展开更多
关键词 activated carbon RUTHENIUM Supported catalyst Ammonia synthesis
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Hydrogenation of ortho-nitrochlorobenzene on activated carbon supported platinum catalysts 被引量:2
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作者 蒋成君 尹红 陈志荣 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第5期378-381,共4页
Platinum/carbon catalyst is one of the most important catalysts in hydrogenation of ortho-nitrochlorobenzene to 2,2′-dichlorohydrazobenzene. The preparation process and the supports of catalysts are studied in this p... Platinum/carbon catalyst is one of the most important catalysts in hydrogenation of ortho-nitrochlorobenzene to 2,2′-dichlorohydrazobenzene. The preparation process and the supports of catalysts are studied in this paper. Raw materials and preparation procedure of the activated carbon have great influences on the compositions and surface structure of platinum/carbon catalysts. Platinum catalysts supported on activated carbon with high purity, high surface area, large pore volume and appropriate pore structure usually exhibit higher activities for hydrogenation of ortho-nitrochlorobenzene to 2,2′-dichlorohydrazobenzene. The catalyst prepared from H2PtCl6 with pH=3 shows greater catalytic performance than those prepared under other conditions. 展开更多
关键词 Platinum/carbon catalyst HYDROGENATION Ortho-nitrochlorobenzene 2 2′-dichlorohydrazobenzene activated carbon
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Phenol hydrogenation to cyclohexanone over palladium nanoparticles loaded on charming activated carbon adjusted by facile heat treatment 被引量:2
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作者 Chunhua Zhang Guangxin Yang +3 位作者 Hong Jiang Yefei Liu Rizhi Chen Weihong Xing 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第10期2600-2606,共7页
Selective phenol hydrogenation is a green approach to produce cyclohexanone.It still remains a big challenge to prepare efficient supports of the catalysts for the phenol hydrogenation via a simple and cost-effective ... Selective phenol hydrogenation is a green approach to produce cyclohexanone.It still remains a big challenge to prepare efficient supports of the catalysts for the phenol hydrogenation via a simple and cost-effective approach.Herein,a facile approach was developed,i.e.,direct calcination of activated carbon(AC)under argon at high temperature,to improve its structure and surface properties.The modified AC materials were supported with Pd nanoparticles(NPs)to fabricate the Pd/C catalysts.The as-prepared Pd/C600 catalyst exhibits superior catalytic performance in the phenol hydrogenation,and its turnover frequency(TOF)value is 199.2 h^-1,1.31 times to that of Pd/C-raw.The Pd/C600 catalyst presents both better hydrophobicity and more structural defects,contributing to the improved dispersibility in the reaction solution(phenol-cyclohexane),the better Pd dispersion and the smaller Pd size,which result in the enhancement of the catalytic performance.Furthermore,the as-prepared Pd/C600 catalyst shows a good recyclability. 展开更多
关键词 CYCLOHEXANONE PHENOL HYDROGENATION activated carbon catalyst
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Preparation of Low Cost Activated Carbon from Deactivated Resin Catalyst for Methyl Tert-Butyl Ether Synthesis and Its Application in Dimethyl Sulfide Adsorption with Transition Metal Impregnation 被引量:1
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作者 Yu Zhan Shi Li Meng Xuan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2017年第2期55-64,共10页
In this paper, a low-cost activated carbon(AC) was prepared from deactivated resin catalyst(DRC) for methyl tert-butyl ether(MTBE) synthesis through carbonization and subsequent steam activation treatment. The activat... In this paper, a low-cost activated carbon(AC) was prepared from deactivated resin catalyst(DRC) for methyl tert-butyl ether(MTBE) synthesis through carbonization and subsequent steam activation treatment. The activated carbon was characterized in detail. After loading various transition metals, including Cu^(2+), Ag+, Co^(2+), Ni^(2+), Zn^(2+), and Fe^(3+) via the ultrasonic-assisted impregnation method, a series of metal-loaded adsorbents(xM-AC) were obtained and their dimethyl sulfide(DMS) adsorption performance was investigated in a batch system. Among these adsorbents, 15Cu-AC presented a superior DMS adsorption capacity equating to 58.986 mg/g due to the formation of S-M(σ) bonds between Cu^(2+) and sulfur atoms of DMS as confirmed by the Raman spectra and kinetic study. 展开更多
关键词 activated carbon deactivated RESIN catalyst DIMETHYL SULFIDE transition metal
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Low-Temperature Denitrification Performance of Cu2O/Activated Carbon Catalysts for Selective Catalytic Reduction of NOx by CO 被引量:2
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作者 WANG Defu HUANG Bangfu +3 位作者 LONG Hongming SHI Zhe LIU Lanpeng LI Lu 《Journal of Donghua University(English Edition)》 EI CAS 2020年第5期382-388,共7页
To improve the denitrification performance of carbon-based materials for sintering flue gas,we prepared a composite catalyst comprising coconut shell activated carbon(AC)modified by thermal oxidation air.The microstru... To improve the denitrification performance of carbon-based materials for sintering flue gas,we prepared a composite catalyst comprising coconut shell activated carbon(AC)modified by thermal oxidation air.The microstructure,the specific surface area,the pore volume,the crystal structure,and functional groups presented in the prepared Cu2O/AC catalysts were thoroughly characterized.By using scanning electron microscopy(SEM),nitrogen adsorption/desorption isotherms,Fourier-transform infrared(FTIR)spectroscopy and X-ray diffractometry(XRD),the effects of Cu2O loading and calcination temperature on Cu2O/AC catalysts were investigated at low temperature(150℃).The research shows that Cu on the Cu2O/AC catalyst is in the form of Cu2O with good crystalline performance and is spherical and uniformly dispersed on the AC surface.The loading of Cu2O increases the active sites and the specific surface area of the reaction gas contact,which is conducive to the rapid progress of the carbon monoxide selective catalytic reduction(CO-SCR)reaction.When the loading of Cu2O was 8%and the calcination temperature was 500℃,the removal rate of NOx facilitated by the Cu2O/AC catalyst reached 97.9%.These findings provide a theoretical basis for understanding the denitrification of sintering flue gas. 展开更多
关键词 thermal oxidation coconut shell activated carbon(AC) Cu2O/AC catalyst carbon monoxide selective catalytic reduction(CO-SCR) denitrification performance
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Promotion effect of adsorbed water/OH on the catalytic performance of Ag/activated carbon catalysts for CO preferential oxidation in excess H_2
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作者 Yuanyuan Guo Limin Chen +2 位作者 Ding Ma Daiqi Ye Bichun Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第4期591-598,共8页
Activated carbon (AC) supported silver catalysts were prepared by incipient wetness impregnation method and their catalytic performance for CO preferential oxidation (PROX) in excess H2 was evaluated. Ag/AC cataly... Activated carbon (AC) supported silver catalysts were prepared by incipient wetness impregnation method and their catalytic performance for CO preferential oxidation (PROX) in excess H2 was evaluated. Ag/AC catalysts, after reduction in H2 at low temperatures (≤200 ℃) following heat treatment in He at 200 ℃ (He200H200), exhibited the best catalytic properties. Temperature-programmed desorption (TPD), X-ray diffraction (XRD) and temperature-programmed reduction (TPR) results indicated that silver oxides were produced during heat treatment in He at 200 ℃ which were reduced to metal silver nanoparticles in H2 at low temperatures (≤200 ℃), simultaneously generating the adsorbed water/OH. CO conversion was enhanced 40% after water treatment following heat treatment in He at 600 ℃. These results imply that the metal silver nanoparticles are the active species and the adsorbed water/OH has noticeable promotion effects on CO oxidation. However, the promotion effect is still limited compared to gold catalysts under the similar conditions, which may be the reason of low selectivity to CO oxidation in PROX over silver catalysts. The reported Ag/AC-S-He catalyst after He200H200 treatment displayed similar PROX of CO reaction properties to Ag/SiO2. This means that Ag/AC catalyst is also an efficient low-temperature CO oxidation catalyst. 展开更多
关键词 promotion effect adsorbed water/OH Ag/activated carbon (Ag/AC) catalysts CO preferential oxidation (PROX)
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Photocatalytic activity and kinetics for acid yellow degradation over surface composites of TiO_2-coated activated carbon under different photocatalytic conditions 被引量:3
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作者 曾孟雄 李佑稷 +2 位作者 马明远 陈伟 李雷勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1019-1027,共9页
TiO2-coated activated carbon surface (TAs) composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow (AY) was investigated under UV radiation to es... TiO2-coated activated carbon surface (TAs) composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow (AY) was investigated under UV radiation to estimate activity of catalysts and determine the kinetics. And the effects of parameters including the initial concentration of AY, light intensity and TiO2 content in catalysts were examined. The results indicate that TAs has a higher efficiency in decomposition of AY than P25, pure TiO2 particles as well as the mixture of TiO2 powder and active carbon. The photocatalytic degradation rate is found to follow the pseudo-first order kinetics with respect to the AY concentration. The new kinetic model fairly resembles the classic Langmuir-Hinshelwood equation, and the rate constant is proportional to the square root of the light intensity in a wide range. However, its absorption performance depends on the surface areas of catalysts. The model fits quite well with the experimental data and elucidates phenomena about the effects of the TiO2 content in TAs on the degradation rate. 展开更多
关键词 PHOTOCATALYSIS TiO2-coated activated carbon acid yellow composite catalyst
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Carbon‐based metal‐free catalysts for electrochemical CO2 reduction: Activity, selectivity, and stability 被引量:11
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作者 Israr Masood ul Hasan Luwei Peng +5 位作者 Jianfeng Mao Ruiman He Yongxia Wang Jing Fu Nengneng Xu Jinli Qiao 《Carbon Energy》 CAS 2021年第1期24-49,共26页
Zero or negative emissions of carbon dioxide(CO2)is the need of the times,as inexorable rising and alarming levels of CO2 in the atmosphere lead to global warming and severe climate change.The electrochemical CO2 redu... Zero or negative emissions of carbon dioxide(CO2)is the need of the times,as inexorable rising and alarming levels of CO2 in the atmosphere lead to global warming and severe climate change.The electrochemical CO2 reduction(eCO2R)to value‐added fuels and chemicals by using renewable electricity provides a cleaner and more sustainable route with economic benefits,in which the key is to develop clean and economical electrocatalysts.Carbon‐based catalyst materials possess desirable properties such as high offset potential for H2 evolution and chemical stability at the negative applied potential.Although it is still challenging to achieve highly efficient carbon‐based catalysts,considerable efforts have been devoted to overcoming the low selectivity,activity,and stability.Here,we summarize and discuss the recent progress in carbon‐based metal‐free catalysts including carbon nanotubes,carbon nanofibers,carbon nanoribbons,graphene,carbon nitride,and diamonds with an emphasis on their activity,product selectivity,and stability.In addition,the key challenges and future potential approaches for efficient eCO2R to low carbon‐based fuels are highlighted.For a good understanding of the whole history of the development of eCO2R,the CO2 reduction reactions,principles,and techniques including the role of electrolytes,electrochemical cell design and evaluation,product selectivity,and structural composition are also discussed.The metal/metal oxides decorated with carbon‐based electrocatalysts are also summarized.We aim to provide insights for further development of carbon‐based metal‐free electrocatalysts for CO2 reduction from the perspective of both fundamental understanding and technological applications in the future. 展开更多
关键词 activITY carbon‐based catalyst CO2 electrochemical reduction SELECTIVITY STABILITY
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Surface chemical characterization of deactivated low-level mercury catalysts for acetylene hydrochlorination 被引量:1
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作者 Chao Liu Chenhui Liu +3 位作者 Jinhui Peng Libo Zhang Shixing Wang Aiyuan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第2期364-372,共9页
Mercury-containing catalysts are widely used for acetylene hydrochlorination in China. Surface chemical characteristics of the fresh low-level mercury catalysts and spent low-level mercury catalysts were compared usin... Mercury-containing catalysts are widely used for acetylene hydrochlorination in China. Surface chemical characteristics of the fresh low-level mercury catalysts and spent low-level mercury catalysts were compared using multiple characterization methods. Pore blockage and active site coverage caused by chlorine-containing organics are responsible for catalyst deactivation. The reactions of chloroethylene and acetylene with chlorine free radical can generate chlorine-containing organic species. SiO_2 and functional groups on activated carbon contribute to the generation of carbon deposition. No significant reduction in the total content of mercury was observed after catalyst deactivation, while there was mercury loss locally. The irreversible loss of HgCl_2 caused by volatilization, reduction and poisoning of elements S and P also can lead to catalyst deactivation. Si, Al, Ca and Fe oxides are scattered on the activated carbon. Active components are still uniformly absorbed on activated carbon after catalyst deactivation. 展开更多
关键词 catalyst activated carbon Deactivation Mercuric chloride Acetylene hydrochlorination carbon deposition
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Enantioselective Alternating Copolymerization of Propylene with Carbon Monoxide Using Cationic Palladium-Chiral Diphosphine Catalyst
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作者 Jian Chao YUAN Yu Hua ZHANG Shi Jie LU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期519-522,共4页
Enantioselective alternating copolymerization of carbon monoxide with propylene was carried out using palladium catalyst modified by 1,4-3,6-dianhydro-2,5-dideoxy-2,5-bis (diphenylphosphino)-L-iditol (DDPPI). The chir... Enantioselective alternating copolymerization of carbon monoxide with propylene was carried out using palladium catalyst modified by 1,4-3,6-dianhydro-2,5-dideoxy-2,5-bis (diphenylphosphino)-L-iditol (DDPPI). The chiral diphosphine was proved to be effective at enantioselective copolymerization. Optical rotation, elemental analysis, H-1, C-13-NMR and IR spectra showed that the copolymer was optically active, isotactic, alternating poly(1,4-ketone) structure. 展开更多
关键词 palladium catalyst chiral ligand enantioselective alternating copolymerization isotactic copolymer optical activity
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Potassium-decorated active carbon supported Co-Mo-based catalyst for water-gas shift reaction
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作者 Yixin Lian RuiFen Xiao +1 位作者 Weiping Fang Yiquan Yang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第1期77-83,共7页
The effect of potassium-decoration was studied on the activity of water-gas shift (WGS) reaction over the Co-Mo-based catalysts supported on active carbon (AC), which was prepared by incipient wetness co-impregnat... The effect of potassium-decoration was studied on the activity of water-gas shift (WGS) reaction over the Co-Mo-based catalysts supported on active carbon (AC), which was prepared by incipient wetness co-impregnation method. The decoration of potassium on active carbon in advance enhances the activities of the CoMo-K/AC catalysts for WGS reaction. Highest activity (about 92% conversion) was obtained at 250 ? C for the catalyst with an optimum K 2 O/AC weight ratio in the range from 0.12 to 0.15. The catalysts were characterized by TPR and EPR, and the results show that activated carbon decorated with potassium makes Co-Mo species highly dispersed, and thus easily reduced and sulfurized. XRD results show that an appropriate content of potassium-decoration on active carbon supports may favors the formation of highly dispersed Co 9 S 8 -type structures which are situated on the edge or a site in contact with MoS 2 , K-Mo-O-S, Mo-S-K phase. Those active species are responsible for the high activity of CoMo-K/AC catalysts. 展开更多
关键词 active carbon potassium-decorated active phase Co-Mo-based catalyst water-gas shift
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STUDIES ON THE CATALYTIC REACTION OF NITROGEN OXIDE ON METAL MODIFIED ACTIVATED CARBON FIBERS
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作者 FURuowen DUXiuying +2 位作者 LINYuansheng XUHao HUYiongjun 《Chinese Journal of Reactive Polymers》 2003年第1期17-25,共9页
The catalytic reaction of NO with CO and decomposition of NO over metal modified ACFs were investigated and compared with other carriers supported catalysts. It is demonstrated that Pd/ACF and Pd/Cu/ACF have high cata... The catalytic reaction of NO with CO and decomposition of NO over metal modified ACFs were investigated and compared with other carriers supported catalysts. It is demonstrated that Pd/ACF and Pd/Cu/ACF have high catalytic activity for the reaction of NO/CO, while Pt/ACF, Pt/Cu/ACF and Co/Cu/ACF have very low catalytic activity in similar circumstance. Pd-modified ACF possesses high catalytic decomposition of NO at 300℃. Pd/CB and Pd/GAC present good catalytic decomposition ability for NO only at low flowrate. Pd/G, Pd/ZMS and Pd/A however, do not show any catalytic activity for NO decomposition even at 400℃. Catalytic temperature, NO flowrate and loading of metal components affect the decomposition rate of NO. The coexistence of Cu with Pd on Cu/Pd/ACF leads to crystalline of palladium to more unperfected so as to that increase the catalytic activity. 展开更多
关键词 activated carbon fiber palladium Catalytic reduction Catalytic decomposition Nitrogen monoxide
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High activity of a Pt decorated Ni/C nanocatalyst for hydrogen oxidation 被引量:3
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作者 高孝麟 王昱飞 +2 位作者 谢和平 刘涛 储伟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期396-403,共8页
The Pt decorated Ni/C nanocatalysts were prepared for hydrogen oxidation reaction(HOR) in fuel cell.By regulating the contents of Pt and Ni in the catalyst,both the composition and the structure affected the electro... The Pt decorated Ni/C nanocatalysts were prepared for hydrogen oxidation reaction(HOR) in fuel cell.By regulating the contents of Pt and Ni in the catalyst,both the composition and the structure affected the electrochemical catalytic characteristics of the Pt-Ni/C catalysts.When the Pt mass content was 3.1% percent and that of Ni was 13.9% percent,the Pt-Ni/C-3 catalyst exhibited a larger electrochemically active surface area and a higher exchange current density toward HOR than those of pure supported platinum sample.Our study demonstrates a feasible approach for designing the more efficient catalysts with lower content of noble metal for HOR in fuel cell. 展开更多
关键词 Platinum catalyst Galvanic displacement Nickel supported on carbon Hydrogen oxidation reaction Electrochemically active surface
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Nanocarbons and their hybrids as catalysts for non-aqueous lithium–oxygen batteries 被引量:5
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作者 Yunchuan Tu Dehui Deng Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期957-966,共10页
Rechargeable lithium-oxygen (Li–O2) batteries have been considered as the most promising candidates for energy storage and conversion devices because of their ultra high energy density. Until now, the critical scient... Rechargeable lithium-oxygen (Li–O2) batteries have been considered as the most promising candidates for energy storage and conversion devices because of their ultra high energy density. Until now, the critical scientific challenges facing Li–O2batteries are the absence of advanced electrode architectures and highly efficient electrocatalysts for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), which seriously hinder the commercialization of this technology. In the last few years, a number of strategies have been devoted to exploring new catalysts with novel structures to enhance the battery performance. Among various of oxygen electrode catalysts, carbon-based materials have triggered tremendous attention as suitable cathode catalysts for Li–O2batteries due to the reasonable structures and the balance of catalytic activity, durability and cost. In this review, we summarize the recent advances and basic understandings related to the carbon-based oxygen electrode catalytic materials, including nanostructured carbon materials (one-dimensional (1D) carbon nanotubes and carbon nanofibers, 2D graphene nanosheets, 3D hierarchical architectures and their doped structures), and metal/metal oxide-nanocarbon hybrid materials (nanocarbon supporting metal/metal oxide and nanocarbon encapsulating metal/metal oxide). Finally, several key points and research directions of the future design for highly efficient catalysts for practical Li–O2batteries are proposed based on the fundamental understandings and achievements of this battery field. © 2016 Science Press 展开更多
关键词 carbon nanofibers catalyst activity catalystS Electric batteries Electrocatalysis Electrocatalysts Electrodes Electrolytic reduction LITHIUM Lithium batteries OXYGEN Secondary batteries YARN
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Effects of the Different Supports on the Activity and Selectivity of Iron-Cobalt Bimetallic Catalyst for Fischer-Tropsch Synthesis 被引量:3
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作者 Xiangdong Ma Qiwen Sun +2 位作者 Fahai Cao Weiyong Ying Dingye Fang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第4期335-339,共5页
Silica, alumina, and activated carbon supported iron-cobalt catalysts were prepared by incipient wetness impregnation. These catalysts have been characterized by BET, X-ray diffraction (XRD), and temperature-program... Silica, alumina, and activated carbon supported iron-cobalt catalysts were prepared by incipient wetness impregnation. These catalysts have been characterized by BET, X-ray diffraction (XRD), and temperature-programmed reduction (TPR). Activity and selectivity of iron-cobalt supported on different carriers for CO hydrogenation were studied under the conditions of 1.5 MPa, 493 K, 630 h^-1, and H2/CO ratio of 1.6. The results indicate that the activity, C4 olefin/(C4 olefin+C4 paraffin) ratio, and C5 olefin/(C5 olefin+C5 paraffin) decrease in the order of Fe-Co/SiO2, Fe-Co/AC1, Fe-Co/Al2O3 and Fe- Co/AC2. The activity of Fe-Co/SiO2 reached a maximum. The results of TPR show that the Fe-Co/SiO2 catalyst is to some extent different. XRD patterns show that the Fe-Co/SiO2 catalyst differs significantly from the others; it has two diffraction peaks. The active spinel phase is correlated with the supports. 展开更多
关键词 Fischer-Tropsch synthesis bimetallic catalyst iron COBALT support silica ALUMINA active carbon SYNGAS
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Palladium and carbon synergistically catalyzed room-temperature hydrodeoxygenation(HDO) of vanillyl alcohol–A typical lignin model molecule 被引量:1
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作者 Qi Wang Neeraj Gupta +2 位作者 Guodong Wen Sharifah Bee Abd Hamid Dang Sheng Su 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第1期8-16,共9页
Vanillyl alcohol, which is made up of an aromatic ring, an alcoholic hydroxyl group, a phenolic hydroxyl group and a methoxy group, was selected as the model molecule of lignin. Various carbon materials supported Pd c... Vanillyl alcohol, which is made up of an aromatic ring, an alcoholic hydroxyl group, a phenolic hydroxyl group and a methoxy group, was selected as the model molecule of lignin. Various carbon materials supported Pd catalysts were chosen to catalyze the HDO of vanillyl alcohol. The catalysts were characterized via TEM, TPD, XRD, XPS and CO-chemisorption. It was found that different carbon materials could obviously influence the particle sizes, dispersion and distribution of Pd or PdO particles. Palladium and carbon can synergistically catalyze the room-temperature HDO of vanillyl alcohol even at room temperature, and the carboxyl group was found to be the effective active acid site during the reaction. Possible reaction mechanism was also proposed. The existence of the effective active acid sites on the carbon supports could obviously lower the reaction temperature without decreasing the selectivity, as a result, making the production of renewable fuels by HDO much more economically feasible, which is of much importance. © 2016 Science Press 展开更多
关键词 Bioconversion carbon catalysts DISPERSIONS Molecules palladium
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Insight into MgO promoter with low concentration for the carbon-deposition resistance of Ni-based catalysts in the CO_2 reforming of CH_4 被引量:4
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作者 Xiangdong Feng Jie Feng Wenying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第1期88-98,共11页
The CO2reforming of CH4is studied over MgO‐promoted Ni catalysts,which were supported on alumina prepared from hydrotalcite.This presents an improved stability compared with non‐promoted catalysts.The introduction o... The CO2reforming of CH4is studied over MgO‐promoted Ni catalysts,which were supported on alumina prepared from hydrotalcite.This presents an improved stability compared with non‐promoted catalysts.The introduction of the MgO promoter was achieved through the‘‘memory effect’’of the Ni‐Al hydrotalcite structure,and ICP‐MS confirmed that only0.42wt.%of Mg2+ions were added into the Ni‐Mg/Al catalyst.Although no differences in the Ni particle size and basicity strength were observed,the Ni‐Mg/Al catalyst showed a higher catalytic stability than the Ni/Al catalyst.A series of surface reaction experiments were used and showed that the addition of a MgO promoter with low concentration can promote CO2dissociation to form active surface oxygen arising from the formation of the Ni‐MgO interface sites.Therefore,the carbon‐resistance promotion by nature was suggested to contribute to an oxidative environment around Ni particles,which would increase the conversion of carbon residues from CH4cracking to yield CO on the Ni metal surface.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved. 展开更多
关键词 CO2 reforming of CH4 carbon‐deposition resistant activation of CO2 Ni‐based catalyst Low concentration MgO promoter
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