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Synthesis of light hydrocarbons over Fe/AC catalysts 被引量:1
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作者 Zhao Jianjun Zong Zhimin +2 位作者 Wang Taotao Liu Tong Wei Xianyong 《International Journal of Mining Science and Technology》 2012年第2期209-212,共4页
A series of Fe/AC catalysts for catalytic hydrogenation of CO to light hydrocarbons(LHCs) were prepared by decomposing Fe(CO)5 in an autoclave.The catalysts activities were tested in a high-pressure micro reactor.The ... A series of Fe/AC catalysts for catalytic hydrogenation of CO to light hydrocarbons(LHCs) were prepared by decomposing Fe(CO)5 in an autoclave.The catalysts activities were tested in a high-pressure micro reactor.The results show that both CO conversion and LHCs selectivity were significantly affected by the amount of Fe loaded onto the catalysts.The optimum Fe content was determined to be 10% by weight of the catalyst.Over the corresponding catalyst(i.e.,10% Fe/C catalyst),the conversion of CO and the selectivity of LHCs were 94.8% and 59.2%,respectively,at 360 °C.Based on various catalyst characterization techniques,such as XRD,BET and SEM,the catalysts surface areas and pore volume decreased and the smaller particles agglomerated at the edges and corners in the outer region of the support with the increasing Fe content.The agglomerated particles increased greatly when the iron content of the catalyst was higher than 10%.The decrease of catalyst activity can be due to the agglomerated particles. 展开更多
关键词 CO hydrogenationfe/ac catalystsLight hydrocarbonsParticles agglomerated
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The high catalytic activity and strong stability of 3%Fe/AC catalysts for catalytic wet peroxide oxidation of m-cresol: The role of surface functional groups and FeO_(x) particles 被引量:1
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作者 Peiwei Han Chunhua Xu +5 位作者 Yamin Wang Chenglin Sun Huangzhao Wei Haibo Jin Ying Zhao Lei Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第4期105-114,共10页
FeO;supported on activated carbon(AC) has been shown to be an ideal catalyst for catalytic wet peroxide oxidation(CWPO) due to its high CWPO reaction activity and stability. Although there have been some studies on th... FeO;supported on activated carbon(AC) has been shown to be an ideal catalyst for catalytic wet peroxide oxidation(CWPO) due to its high CWPO reaction activity and stability. Although there have been some studies on the mechanism of Fe/AC catalysis in CWPO, the specific contribution of each component(surface oxygen groups and FeOxon AC) inside an Fe/AC catalyst and their corresponding reaction mechanism remain unclear, and the reaction stability of CWPO catalysts has rarely been discussed. Then the optimal CWPO catalyst in our laboratory, 3%Fe/AC, was selected.(1) By removing certain components on the AC through heat treatment, its contribution to the reaction and the corresponding reaction mechanism were investigated. With the aid of temperature-programmed desorption–mass spectrometry(TPD–MS) and the CWPO reaction, the normalized catalytic contributions of components were shown to be: 37.3%(carboxylic groups), 5.3%(anhydride), 19.3%(ether/hydroxyl),-71.4%(carbonyl groups) and 100%(FeOx),respectively. DFT calculation and EPR analysis confirmed that carboxylic groups and Fe_(2)O_(3) are able to activate the H_(2)O_(2) to generate·OH.(2) The catalysts at were characterized at different reaction times(0 h, 450 h, 900 h, 1350 h, and 1800 h) by TPD–MS and M?ssbauer spectroscopy. Results suggested that the number of carboxylic goups gradually increased and the size of paramagnetic Fe_(2)O_(3) particle crystallites gradually increased as the reactions progressed. The occurrence of strong interactions between metal oxides and AC was also confirmed. Due to these effects, the strong stability of 3%Fe/AC was further improved. Therefore, the reasons for the high activity and strong stability of 3%Fe/AC in CWPO were clearly shown. We believe that this work provides an idea of the removal of cresols from wastewater into the introduction to show the potential applications of CWPO. 展开更多
关键词 Catalytic wet peroxide oxidation fe/ac catalyst Surface functional groups Reaction mechanism
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Polygonal mesopores microflower catalysts for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene to 2-nitro-4-methylsulfonylbenzoic acid in a continuous-flow microreactor
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作者 Jianzhi Wang Xugen Li +6 位作者 Cheng Zhang Yuan Pu Jiawu Liu Jie Liu Yanping Liu Xiao Lin Faquan Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期212-221,共10页
The development of efficient systems for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene(NMST)to 2-nitro-4-methylsulfonyl benzoic acid(NMSBA)with atmospheric air or molecular oxygen in alkaline medium prese... The development of efficient systems for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene(NMST)to 2-nitro-4-methylsulfonyl benzoic acid(NMSBA)with atmospheric air or molecular oxygen in alkaline medium presents a significant challenge for the chemical industry.Here,we report the synthesis of FeOOH/Fe_(3)O_(4)/metal-organic framework(MOF)polygonal mesopores microflower templated from a MIL-88B(Fe)at room temperature,which exposes polygonal mesopores with atomistic edge steps and lattice defects.The obtained FeOOH/Fe_(3)O_(4)/MOF catalyst was adsorbed onto glass beads and then introduced into the microchannel reactor.In the alkaline environment,oxygen was used as oxidant to catalyze the oxidation of NMST to NMSBA,showing impressive performance.This sustainable system utilizes oxygen as a clean oxidant in an inexpensive and environmentally friendly NaOH/methanol mixture.The position and type of substituent critically affect the products.Additionally,this sustainable protocol enabled gram-scale preparation of carboxylic acid and benzyl alcohol derivatives with high chemoselectivities.Finally,the reactions can be conducted in a pressure reactor,which can conserve oxygen and prevent solvent loss.Moreover,compared with the traditional batch reactor,the self-built microchannel reactor can accelerate the reaction rate,shorten the reaction time,and enhance the selectivity of catalytic oxidation reactions.This approach contributes to environmental protection and holds potential for industrial applications. 展开更多
关键词 2-nitro-4-methylsulfonylbenzoic 2-nitro-4-methylsulfonyltoluene feOOH/fe3O4/MOF catalyst MICROREacTOR Oxidation
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Enhanced activation of peroxymonosulfate by Fe/N co-doped ordered mesoporous carbon with dual active sites for efficient removal of m-cresol 被引量:1
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作者 Donghui Li Wenzhe Wu +6 位作者 Xue Ren Xixi Zhao Hongbing Song Meng Xiao Quanhong Zhu Hengjun Gai Tingting Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期130-144,共15页
The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,th... The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,the complexation of N elements in urea could anchor Fe,and the formation of C3N4during urea pyrolysis could also prevent migration and aggregation of Fe species,which jointly improve the dispersion and stability of Fe.The FeN4sites and highly dispersed Fe nanoparticles synergistically trigger the dual-site peroxymonosulfate (PMS) activation for highly efficient m-cresol degradation,while the ordered mesoporous structure of the catalyst could improve the mass transfer rate of the catalytic process,which together promote catalytic degradation of m-cresol by PMS activation.Reactive oxygen species (ROS) analytic experiments demonstrate that the system degrades m-cresol by free radical pathway mainly based on SO_(4)^(-)·and·OH,and partially based on·OH as the active components,and a possible PMS activation mechanism by 5Fe-50 for m-cresol degradation was proposed.This study can provide theoretical guidance for the preparation of efficient and stable catalysts for the degradation of organic pollutants by activated PMS. 展开更多
关键词 Degradation PEROXYMONOSULFATE fe(II)/fe(III)/feN4 Ordered mesopores carbon catalyst Radical
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Atomically dispersed Fe sites on hierarchically porous carbon nanoplates for oxygen reduction reaction
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作者 Ruixue Zheng Qinglei Meng +9 位作者 Hao Zhang Teng Li Di Yang Li Zhang Xiaolong Jia Changpeng Liu Jianbing Zhu Xiaozheng Duan Meiling Xiao Wei Xing 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期7-15,I0002,共10页
Developing cost-effective,robust and stable non-precious metal catalysts for oxygen reduction reaction(ORR) is of paramount importance for electrochemical energy conversion devices such as fuel cells and metal-air bat... Developing cost-effective,robust and stable non-precious metal catalysts for oxygen reduction reaction(ORR) is of paramount importance for electrochemical energy conversion devices such as fuel cells and metal-air batteries.Although Fe-N-C single atom catalysts(SACs) have been hailed as the most promising candidate due to the optimal binding strength of ORR intermediates on the Fe-N_(4) sites,they suffer from serious mass transport limitations as microporous templates/substrates,i.e.,zeolitic imidazolate frameworks(ZIFs),are usually employed to host the active sites.Motivated by this challenge,we herein develop a hydrogen-bonded organic framework(HOF)-assisted pyrolysis strategy to construct hierarchical micro/mesoporous carbon nanoplates for the deposition of atomically dispersed Fe-N_(4) sites.Such a design is accomplished by employing HOF nanoplates assembled from 2-aminoterephthalic acid(NH_(2)-BDC) and p-phenylenediamine(PDA) as both soft templates and C,N precursors.Benefitting from the structural merits inherited from HOF templates,the optimized catalyst(denoted as Fe-N-C SAC-950) displays outstanding ORR activity with a high half-wave potential of 0.895 V(vs.reversible hydrogen electrode(RHE)) and a small overpotential of 356 mV at 10 mA cm^(-2) for the oxygen evolution reaction(OER).More excitingly,its application potential is further verified by delivering superb rechargeability and cycling stability with a nearly unfading charge-discharge gap of 0.72 V after 160 h.Molecular dynamics(MD) simulations reveal that micro/mesoporous structure is conducive to the rapid mass transfer of O_(2),thus enhancing the ORR performance.In situ Raman results further indicate that the conversion of O_(2) to~*O_(2)-the rate-determining step(RDS) for Fe-N-C SAC-950.This work will provide a versatile strategy to construct single atom catalysts with desirable catalytic properties. 展开更多
关键词 fe single atom catalysts Oxygen reduction reaction Mesoporous structure active sites Zinc-air battery
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Low-temperature Denitration Mechanism of NH_(3)-SCR over Fe/AC Catalyst
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作者 杨征宇 黄帮福 +3 位作者 ZHANG Guifang DAI Meng WEN Zhenjing LI Wanjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期475-484,共10页
To study the modification mechanism of activated carbon(AC)by Fe and the low-temperature NH_(3)-selective catalytic reduction(SCR)denitration mechanism of Fe/AC catalysts,Fe/AC catalysts were prepared using coconut sh... To study the modification mechanism of activated carbon(AC)by Fe and the low-temperature NH_(3)-selective catalytic reduction(SCR)denitration mechanism of Fe/AC catalysts,Fe/AC catalysts were prepared using coconut shell AC activated by nitric acid as the support and iron oxide as the active component.The crystal structure,surface morphology,pore structure,functional groups and valence states of the active components of Fe/AC catalysts were characterised by X-ray diffraction,scanning electron microscopy,nitrogen adsorption and desorption,Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy,respectively.The effect of Fe loading and calcination temperature on the low-temperature denitration of NH_(3)-SCR over Fe/AC catalysts was studied using NH_(3)as the reducing gas at low temperature(150℃).The results show that the iron oxide on the Fe/AC catalyst is spherical and uniformly dispersed on the surface of AC,thereby improving the crystallisation performance and increasing the number of active sites and specific surface area on AC in contact with the reaction gas.Hence,a rapid NH_(3)-SCR reaction was realised.When the roasting temperature remains constant,the iron oxide crystals formed by increasing the amount of loading can enter the AC pore structure and accumulate to form more micropores.When the roasting temperature is raised from 400 to 500℃,the iron oxide is mainly transformed fromα-Fe_(2)O_(3)toγ-Fe_(2)O_(3),which improves the iron oxide dispersion and increases its denitration active site,allowing gas adsorption.When the Fe loading amount is 10%,and the roasting temperature is 500℃,the NO removal rate of the Fe/AC catalyst can reach 95%.According to the study,the low-temperature NH_(3)-SCR mechanism of Fe/AC catalyst is proposed,in which the redox reaction between Fe~(2+)and Fe~(3+)will facilitate the formation of reactive oxygen vacancies,which increases the amount of oxygen adsorption on the surface,especially the increase in surface acid sites,and promotes and adsorbs more reaction gases(NH_(3),O_(2),NO).The transformation from the standard SCR reaction to the fast SCR reaction is accelerated. 展开更多
关键词 nitric acid activation method coconut shell activated carbon fe/ac catalyst NH_(3)-SCR low-temperature denitrification mechanism
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Treatment of Phenol Wastewater with Cu-Fe/AC Catalyst by Continuous CWPO
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作者 Yue XU Hongzhu XU +3 位作者 Caixia LU Jinlong SUN Lianfeng WANG Lin TIAN 《Meteorological and Environmental Research》 CAS 2023年第2期72-77,共6页
The Cu-Fe/AC catalyst was prepared by microwave-assisted synthesis, and its morphological characteristics were characterized. The degradation effect of phenol wastewater by catalytic wet peroxide oxidation(CWPO) was s... The Cu-Fe/AC catalyst was prepared by microwave-assisted synthesis, and its morphological characteristics were characterized. The degradation effect of phenol wastewater by catalytic wet peroxide oxidation(CWPO) was studied, and the response surface methodology(RSM) was used to analyze the influencing factors of the removal rate of COD. The experimental results showed that under the conditions of reaction temperature 80 ℃, reaction time 90 min, initial pH 3.1 and H_(2)O_(2)addition 2.2 g/L, the removal rate of COD reached 82%. The results of response surface methodology indicated that under the conditions of reaction temperature 100 ℃, reaction time 64 min, initial pH 3.3 and H_(2)O_(2)addition 2.7 g/L, the removal rate of COD was up to 86%. After Cu-Fe/AC catalyst was reused for 4 times, the removal rate of COD was still above 80%, revealing that the catalyst showed good catalytic performance. 展开更多
关键词 Cu-fe/ac catalyst Catalytic wet peroxide oxidation Phenol wastewater Response surface methodology
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Preparation of Fe_2P/Al_2O_3 and FeP/Al_2O_3 catalysts for the hydrotreating reactions 被引量:3
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作者 Yamei Yuan Jiayou Zhang +2 位作者 Hui Chen Qiumei Hou Jianyi Shen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第2期116-121,共6页
A 60%Fe/Al_2O_3 catalyst was prepared by the co-precipitation method.It was reduced by H_2 to produce metallic Fe,which was then sulfided by CS_2 to Fe_(0.96) S and Fe_3S_4 or phosphided by triphenylphosphine(PPh3) in... A 60%Fe/Al_2O_3 catalyst was prepared by the co-precipitation method.It was reduced by H_2 to produce metallic Fe,which was then sulfided by CS_2 to Fe_(0.96) S and Fe_3S_4 or phosphided by triphenylphosphine(PPh3) in liquid phases to Fe2 P and Fe P.It was found that the iron sulfides(Fe0.96 S and Fe_3S_4) exhibited the low activity for the hydrodesulfurization(HDS) reactions.The HDS activity was also low on the Fe(metal)/Al_2O_3 and Fe_2 P/Al_2O_3 catalysts since they were converted into Fe0.96 S and Fe_3S_4 during the HDS reactions.In contrast,the FeP/Al_2O_3 was found to be stable and active for the HDS reactions.In particular,Fe P/Al_2O_3 possessed significantly smaller Fe P particles than Fe P/C,leading to the significant higher HDS activity of FeP/Al_2O_3 than Fe P/C. 展开更多
关键词 fe2P/Al2O3 catalyst feP/Al2O3 catalyst Liquid phase phosphidation PPh3 HYDROTREATING REacTIONS
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Influence of different Fe doping strategies on modulating active sites and oxygen reduction reaction performance of Fe, N-doped carbonaceous catalysts 被引量:1
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作者 Yang Liu Suqiong He +2 位作者 Bing Huang Ziyan Kong Lunhui Guan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期511-520,I0013,共11页
Fe/N/C catalysts,synthesized through the pyrolysis of Fe-doped metal–organic framework (MOF) precursors,have attracted extensive attention owing to their promising oxygen reduction reaction (ORR) catalytic activity i... Fe/N/C catalysts,synthesized through the pyrolysis of Fe-doped metal–organic framework (MOF) precursors,have attracted extensive attention owing to their promising oxygen reduction reaction (ORR) catalytic activity in fuel cells and/or metal-air batteries.However,post-treatments (acid washing,second pyrolysis,and so on) are unavoidable to improve ORR catalytic activity and stability.The method for introducing Fe^(3+) sources (anhydrous Fe Cl_(3)) into the MOF structure,in particular,is a critical step that can avoid time-consuming post-treatments and result in more exposed Fe-N_(x) active sites.Herein,three different Fe doping strategies were systematically investigated to explore their influence on the types of active sites formed and ORR performance.Fe-NC(Zn^(2+)),synthesized by one-step pyrolysis of Fe doped ZIF-8 (Zn^(2+)) precursor which was obtained by adding the anhydrous Fe Cl_(3)source into the Zn(NO_(3))_(2)·6H_(2)O/methanol solution before mixing,possessed the highest Fe-N_(x)active sites due to the high-efficiency substitution of Zn^(2+)ions with Fe^(3+) ions during ZIF-8 growth,the strong interaction between Fe^(3+) ions and N atoms of 2-Methylimidazole (2-MIm),and ZIF-8’s micropore confinement effect.As a result,Fe-NC(Zn^(2+)) presented high ORR activity in the entire p H range (p H=1,7,and 13).At p H=13,Fe-NC(Zn^(2+)) exhibited a half-wave potential (E1/2) of 0.95 V (vs.reversible hydrogen electrode),which was 70 m V higher than that of commercial Pt/C.More importantly,Fe-NC(Zn^(2+)) showed superior ORR stability in neutral media without performance loss after 5,000 cycles.A record-high open-circuit voltage(1.9 V) was obtained when Fe-NC(Zn^(2+)) was used as a cathodic catalyst in assembled Mg-air batteries in neutral media.The assembled liquid and all-solid Mg-air batteries with high performance indicated that Fe-NC(Zn^(2+)) has enormous potential for use in flexible and wearable Mg-air batteries. 展开更多
关键词 Mg-air battery Oxygen reduction reaction Single-atom fe/N/C catalysts fe doping strategies Zeolitic imidazole frameworks
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Preparation and characterization of ultrafine Fe-Cu-based catalysts for CO hydrogenation 被引量:4
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作者 Yunlai Su Yingli Wang Zhongmin Liu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第4期327-331,共5页
The ultrafine particles of a new style Fe-Cu-based catalysts for CO hydrogenation were prepared by impregnating the organic sol of Fe(OH)3 and Cu(OH)2 onto the activated Al2O3, in which the organic sol of Fe(OH)... The ultrafine particles of a new style Fe-Cu-based catalysts for CO hydrogenation were prepared by impregnating the organic sol of Fe(OH)3 and Cu(OH)2 onto the activated Al2O3, in which the organic sol of Fe(OH)3 and Cu(OH)2 were prepared in the microemulsion of dodecylbenzenesulfonic acid sodium(S)/n-butanol(A)/toluene(O)/water with V(A)/V(O) = 0.25 and W(A)/W(S) = 1.50. This catalyst was characterized by particle size analysis, XRD and TG. The results of particle size analysis showed that Fe(OH)3 particles with a mean size of 17.1 nm and Cu(OH)2 particles with an average size of 6.65 um were obtained. TG analysis and XRD patterns suggested that 673 K is the optimal calcination temperature. CO hydrogenation produced C+OH with a high selectivity above 58 wt% by using the ultrafine particles as catalyst, and the total alcohol yield of 0.250 g·ml^-1 ·h^-1 was obtained when the contents of Al2O3 and K were 88.61 wt% and 1.60 wt%, respectively. 展开更多
关键词 MICROEMULSION CONDUCTIVITY ultrafine fe-Cu-based catalyst CO hydrogenation
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Oxidative desulfurization of dibenzothiophene over Fe promoted Co–Mo/Al_2O_3 and Ni–Mo/Al_2O_3 catalysts using hydrogen peroxide and formic acid as oxidants 被引量:3
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作者 Yaseen Muhammad Ayesha Shoukat +2 位作者 Ata Ur Rahman Haroon Ur Rashid Waqas Ahmad 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第3期593-600,共8页
This work reports the enhancing effect of a highly cost effective and efficient metal, Fe, incorporation to Co or Ni based Mo/Al2O3 catalysts in the oxidative desulfurization (ODS) of dibenzothiophene (DBT) using ... This work reports the enhancing effect of a highly cost effective and efficient metal, Fe, incorporation to Co or Ni based Mo/Al2O3 catalysts in the oxidative desulfurization (ODS) of dibenzothiophene (DBT) using H2O2 and formic acid as oxidants. The influence of operating parameters i.e. reaction time, catalyst dose, reaction temperature and oxidant amount on oxidation process was investigated. Results revealed that 99% DBT conversion was achieved at 60℃ and 150 min reaction time over Fe-Ni-Mo/Al2O3. Fe tremendously enhanced the ODS activity of Co or Ni based Mo/Al2O3 catalysts following the activity order:Fe-Ni-Mo/Al2O3 〉 Fe-Co-Mo/Al2O3 〉 Ni-Mo/Al2O3 〉 Co-Mo/Al2O3, while H2O2 exhibited higher oxidation activity than formic acid over all catalyst systems. Insight about the surface morphology and textural properties of fresh and spent catalysts were achieved using scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis, Atomic Absorption Spectroscopy (AAS) and BET surface area analysis, which helped in the interpretation of experimental data. The present study can be deemed as an effective approach on industrial level for ODS of fuel oils crediting to its high efficiency, low process/catalyst cost, safety and mild operating condition. 展开更多
关键词 Oxidative desulfurization Fuel oil Dibenzothiophene fe promoted (Co/Ni)-Mo/Al2O3 catalyst XRD
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Catalytic activity of Au/Fe-PILC and Au/Fe-oxide catalysts for catalytic combustion of formaldehyde 被引量:1
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作者 李常艳 沈岳年 +2 位作者 胡瑞生 李沛培 张军 《中国有色金属学会会刊:英文版》 CSCD 2007年第A02期1107-1111,共5页
Iron polymeric hydroxygroups pillared clays(Fe-PILC) were prepared by Na+-montmorillonite with iron pillaring agent. 2.01Au/Fe-PILC catalyst was obtained by deposited-precipitation(DP) method. 2.52Au/Fe-oxide catalyst... Iron polymeric hydroxygroups pillared clays(Fe-PILC) were prepared by Na+-montmorillonite with iron pillaring agent. 2.01Au/Fe-PILC catalyst was obtained by deposited-precipitation(DP) method. 2.52Au/Fe-oxide catalyst was prepared by co-precipitation method. The catalytic activity of these catalysts was measured by catalytic combustion of formaldehyde. The catalyst of 2.01Au/Fe-PILC exhibits the high catalytic activity. The catalytic combustion reaction of formaldehyde proceeds at considerable rates at 20 ℃ and complete burn-off of formaldehyde is achieved at 120 ℃. The structure of catalysts,the valence state of gold and the size of gold particles were investigated by means of X-ray powder diffractometry,X-ray photoelectron spectroscopy and transmission electron microscopy. The results show that gold atoms with partially positive charge exist in the catalyst and play an important role in the catalytic activity. In addition,nano-sized,well-dispersed gold particles and good adsorption properties of support are necessary to obtain high activity Au catalysts for catalytic combustion of formaldehyde. 展开更多
关键词 甲醛 催化燃烧 催化剂 催化活性
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THE INFLUENCE OF SUBSTITUENT ELECTRONIC EFFECT ON ETHYLENE OLIGOMERIZATION ACTIVITIES OF BIS(IMINO)PYRIDYL Fe(Ⅱ) CATALYSTS:A COMBINED MOLECULAR MECHANICS AND CHARGE EQUILIBRATION METHOD
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作者 李化毅 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第5期711-717,共7页
Bis(imino)pyridyl Fe(Ⅱ) complexes are important catalysts in ethylene oligomerization for preparingα-olefins. The metal net charge-activity relationship of bis(imino)pyridyl Fe(Ⅱ) complexes was investigated by mole... Bis(imino)pyridyl Fe(Ⅱ) complexes are important catalysts in ethylene oligomerization for preparingα-olefins. The metal net charge-activity relationship of bis(imino)pyridyl Fe(Ⅱ) complexes was investigated by molecular mechanics (MM) and net charge equilibration(QEq) method with modified Dreiding force field.It was found that metal net charge was in reverse ratio to ethylene oligomerization activity.Electron-donor substituents with less steric hindrance to the central metal were favorable to Fe complex act... 展开更多
关键词 Ethylene OLIGOMERIZATION fe catalyst Molecular mechanics(MM) Net charge equilibration(QEq).
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Cu-Fe Catalysts Modified by Rare Earths for Preparation of High Alcohols from Fatty Acid Esters Reduction
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作者 LIU Shou chang, WANG Hai rong, CHEN Ling Xia (Institute of Industrial Catalysis, Zhengzhou University, Zhengzhou 450052, China) 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期301-301,共1页
In order to increase activity of Cu Fe catalyst and use the mixture of nitrogen and hydrogen directly for preparation of high alcohols by reducing fatty acid esters, rare earths were used to modify the catalyst. Expe... In order to increase activity of Cu Fe catalyst and use the mixture of nitrogen and hydrogen directly for preparation of high alcohols by reducing fatty acid esters, rare earths were used to modify the catalyst. Experiments show that yield of high alcohols increases by 3% as 1% Sm 2O 3 is added to the catalyst when the reduction is carried out under pure hydrogen. The yield greatly decreases when the reduction is carried out under the mixture of hydrogen and nitrogen. Catalysts activities modified by Y and Nd can be evidently improved and even enhanced. The yields increase by 33% and 29% when 1% Y 2O 3 and 1% Nd 2O 3 are added to the catalyst, respectively. 展开更多
关键词 rare earths high alcohols Cu fe catalysts
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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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Spectroscopic Characterization of Mo-Co-S and Mo-Fe-S Complexes-derived Catalysts for Desulfurization and Denitrification
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作者 LIN Guo-dong, LIU Yu-da, YANG Yi-quan and ZHANG Hong-bin(Department of Chemistry and Institute, of Physical Chemistry,Xiamen University, Xiamen, 361005) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第3期188-195,共8页
The characteristic studies, by means of LR, UV-Vis and XPS spectroscopies, of the preparation process of Mo-Co-S and Mo-Fe-S catalysts for HDS and HDN, derived from (NH4)2MoS4-CoCl2 and (NH4)2MoS4-FeCl2 complexes supp... The characteristic studies, by means of LR, UV-Vis and XPS spectroscopies, of the preparation process of Mo-Co-S and Mo-Fe-S catalysts for HDS and HDN, derived from (NH4)2MoS4-CoCl2 and (NH4)2MoS4-FeCl2 complexes supported on γ-Al2O3, respectively, indicate that the catalytically essential moiety on the surface of the catalysts is dominantly some sulfido-bimetallic species with such a structural unit (M' =Co or Fe), and both Co and Fe, served as promoters, can donate electrons to Mo probably via bridging-S. The nature of active-sites and the mechanism of promotion are discussed according to the results. 展开更多
关键词 Mo-Co-S and Mo-fe-S catalysts Desulfurization and denitrification Spectroscopic characterization
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Chemoselective Transfer Hydrogenation of Cinnamaldehyde over Activated Charcoal Supported Pt/Fe3O4 Catalyst 被引量:1
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作者 张勇 陈春 +5 位作者 龚万兵 宋杰瑶 苏燕平 张海民 汪国忠 赵惠军 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期467-473,I0002,共8页
A variety of spherical and structured activated charcoal supported Pt/Fe3O4 composites with an average particle size of ~100 nm have been synthesized by a self-assembly method using the difference of reduction potenti... A variety of spherical and structured activated charcoal supported Pt/Fe3O4 composites with an average particle size of ~100 nm have been synthesized by a self-assembly method using the difference of reduction potential between Pt (Ⅳ) and Fe (Ⅱ) precursors as driving force. The formed Fe3O4 nanoparticles (NPs) effectively prevent the aggregation of Pt nanocrystallites and promote the dispersion of Pt NPs on the surface of catalyst, which will be favorable for the exposure of Pt active sites for high-efficient adsorption and contact of substrate and hydrogen donor. The electron-enrichment state of Pt NPs donated by Fe304 nanocrystallites is corroborated by XPS measurement, which is responsible for promoting and activating the terminal C=O bond of adsorbed substrate via a vertical configuration. The experimental results show that the activated charcoal supported Pt/Fe3O4 catalyst exhibits 94.8% selectivity towards cinnamyl alcohol by the transfer hydrogenation of einnamaldehyde with Pt loading of 2.46% under the optimum conditions of 120 ℃ for 6 h, and 2-propanol as a hydrogen donor. Additionally, the present study demonstrates that a high-efficient and recyclable catalyst can be rapidly separated from the mixture due to its natural magnetism upon the application of magnetic field. 展开更多
关键词 activated charcoal supported Pt/fe3O4 catalysts Redox method Transfer hydrogenation Cinnamaldehyde Cinnamyl alcohol
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Fe-Ca-Ce催化生物质热解制备富氢合成气——以山楂药渣为例
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作者 袁申富 周欣然 +1 位作者 邓晋 孟令帅 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期338-344,共7页
以山楂药渣作为原料,在固定床反应器中研究了热解温度和Fe、Fe-Ca、Fe-Ca-Ce催化剂及负载量对药渣热解的影响规律,并研究了浸渍法和共沉淀法对热解气体产率的影响.研究结果表明,热解温度从500℃升高至700℃,H_(2)由10.40 mL/g升高至27.6... 以山楂药渣作为原料,在固定床反应器中研究了热解温度和Fe、Fe-Ca、Fe-Ca-Ce催化剂及负载量对药渣热解的影响规律,并研究了浸渍法和共沉淀法对热解气体产率的影响.研究结果表明,热解温度从500℃升高至700℃,H_(2)由10.40 mL/g升高至27.64 mL/g,当Fe负载量为w=7%时,H_(2)产率由27.64 mL/g增加至46.16 mL/g,在Fe中引入Ca有效提高了H_(2)的产率,Ca的负载量增加至w=2.0%时,H_(2)产率增加至69.53 mL/g.采用共沉淀法制备Fe和Fe-Ca催化剂有利于降低CO_(2)产率,而在Fe-Ca中引入Ce后H_(2)产率从69.53 mL/g减少至50.18 mL/g. 展开更多
关键词 fe-Ca-Ce催化剂 催化热解 温度 药渣 富氢合成气
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Fe-Mn/AC催化H_(2)O_(2)降解染料废水 被引量:1
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作者 朱冬梅 《佳木斯大学学报(自然科学版)》 CAS 2023年第3期123-126,共4页
通过浸渍法制备的Fe-Mn/AC催化剂以活性炭作为载体,用于降解染料废水。利用SEM手段研究了Fe-Mn/AC催化剂的结构特征。阐述了染料废水的处理方法及制备方法。以甲基橙溶液模拟染料废水,研究了染料废水pH值、染料废水初始浓度、催化剂投... 通过浸渍法制备的Fe-Mn/AC催化剂以活性炭作为载体,用于降解染料废水。利用SEM手段研究了Fe-Mn/AC催化剂的结构特征。阐述了染料废水的处理方法及制备方法。以甲基橙溶液模拟染料废水,研究了染料废水pH值、染料废水初始浓度、催化剂投加量、H_(2)O_(2)浓度对催化剂催化H_(2)O_(2)降解染料废水的影响。实验结果显示,pH值为3,催化剂投加量为0.2g,染料废水初始浓度为50mg/L,H_(2)O_(2)浓度为7.5mmol/L为最佳反应条件。在最优条件下,通过3h的吸附降解处理,染料废水的去除率达到98%。 展开更多
关键词 fe-Mn/ac催化剂 去除率 染料废水 吸附降解
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Aqueous Zinc Batteries with Ultra‑Fast Redox Kinetics and High Iodine Utilization Enabled by Iron Single Atom Catalysts 被引量:6
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作者 Xueya Yang Huiqing Fan +3 位作者 Fulong Hu Shengmei Chen Kang Yan Longtao Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第8期368-380,共13页
Rechargeable aqueous zinc iodine(ZnǀǀI_(2))batteries have been promising energy storage technologies due to low-cost position and constitutional safety of zinc anode,iodine cathode and aqueous electrolytes.Whereas,on ... Rechargeable aqueous zinc iodine(ZnǀǀI_(2))batteries have been promising energy storage technologies due to low-cost position and constitutional safety of zinc anode,iodine cathode and aqueous electrolytes.Whereas,on one hand,the low-fraction utilization of electrochemically inert host causes severe shuttle of soluble polyiodides,deficient iodine utilization and sluggish reaction kinetics.On the other hand,the usage of high mass polar electrocatalysts occupies mass and volume of electrode materials and sacrifices device-level energy density.Here,we propose a“confinement-catalysis”host composed of Fe single atom catalyst embedding inside ordered mesoporous carbon host,which can effectively confine and catalytically convert I_(2)/I^(−)couple and polyiodide intermediates.Consequently,the cathode enables the high capacity of 188.2 mAh g^(−1)at 0.3 A g^(−1),excellent rate capability with a capacity of 139.6 mAh g^(−1)delivered at high current density of 15 A g^(−1)and ultra-long cyclic stability over 50,000 cycles with 80.5%initial capacity retained under high iodine loading of 76.72 wt%.Furthermore,the electrocatalytic host can also accelerate the I^(+)↔I_(2)conversion.The greatly improved electrochemical performance originates from the modulation of physicochemical confinement and the decrease of energy barrier for reversible I−/I_(2)and I_(2)/I^(+)couples,and polyiodide intermediates conversions. 展开更多
关键词 Aqueous zinc batteries Iodine reduction reaction fe single atom catalysts
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