检索结果-南通市图书馆

Synergistic effect of bimetallic RuPt/TiO_(2) catalyst in methane combustion

Rare Metals 2023年第1期42卷 165-175页

作者： Shi-Ying Cao Fan Ye Ni-Ni Zhang Yang-Long Guo Yun Guo Li Wang Sheng Dai Wang-Cheng Zhan Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Centre Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Designing metal compounds based on their structure and chemical composition is essential in achieving desirable performance in methane oxidation,because of the synergistic effect between different metal ***,a bimetallic Ru-Pt catalyst on TiO_(2) support(RuPt-O/TiO_(2)) was prepared by in situ reduction followed by calcination in *** with monometallic catalysts(Ru-O/TiO_(2) and Pt-O/TiO_(2)),the synergistic effect of mixed metals endowed bimetallic catalysts with excellent stability and outstanding performance in methane oxidation,with a reaction rate of 13.9×10^(-5)mol^(-1)_(CH_(4))·g^(-1)_(Ru+Pt)·s^(-1)at 303℃.The varied characterization results revealed that among the bimetallic catalysts,RuO_(2)was epitaxially grown on the TiO_(2) substrate owing to lattice matching between them,and part of the PtO_(x) adhered to the RuO_(2) surface,in addition to a single PtO_(x) nanoparticle with 4 nm in ***,Pt mainly existed in the form of Pt2+and Pt4+and a small amount of zero valence in the bimetallic catalyst,prompting the adsorption and activation of methane as the first and rate-controlling step for CH_(4) *** importantly,the RuO_(2) species provided additional oxygen species to facilitate the redox cycle of the PtO_(x) *** study opens a new route for structurally designing promising catalysts for CH4oxidation.

关键词： Synergistic effect Bimetallic catalyst methane combustion Redox cycle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Surface for methane combustion:O(^3P)+CH4→OH+CH3

引用

Chinese Physics B 2020年第7期29卷 286-294页

作者： Ya Peng Zhong-An Jiang Ju-Shi Chen School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

Kinetic investigations including quasi-classical trajectory and canonical unified statistical theory method calculations are carried out on a potential energy surface for the hydrogen-abstraction reaction from methane by atom O(^3P).The surface is constructed using a modified Shepard interpolation *** ab initio calculations are performed at the CCSD(T)*** account of the contribution of inner core electrons to electronic correlation interaction in ab initio electronic structure calculations,modified optimized aug-cc-pCVQZ basis sets are applied to the all-electrons *** this potential energy surface,the triplet oxygen atom attacks methane in a near-collinear H-CH3 direction to form a saddle point with barrier height of 13.55 kcal/mol,which plays a key role in the kinetics of the title *** the temperature range of 298-2500 K,our calculated thermal rate constants for the O(^3P)+CH4→OH+CH3 reaction show good agreement with relevant experimental *** work provides detailed mechanism of this gas-phase reaction and a theoretical guidance for methane combustion.

关键词： methane combustion potential energy surface transition state kinetic ab initio electronic structure calculation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Component regulation in novel La-Co-O-C composite catalyst for boosted redox reactions and enhanced thermal stability in methane combustion

引用

Journal of Environmental Sciences 2023年第4期126卷 459-469页

作者： Peiqi Chu Saifei Wang Yi Zhang Shiguang Zhao Yahan Wang Jiguang Deng Erhong Duan School of Environmental Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050018China School of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China College of Environmental and Energy Engineering Beijing University of TechnologyBeijing 100124China

A novel La-Co-O-C (LC-C) composites were prepared via a facile co-hydrothermal route with oxides and glycerol and further optimized for methane catalytic activity and thermal stability via component *** was demonstrated that Co3O_(4)phase was the main component in *** combined results of X-ray photoelectron spectroscopy (XPS),temperature-programmed desorption of oxygen (O_(2)-TPD),temperature-programmed reduction of hydrogen (H_(2)-TPR),temperature-programmed desorption of ammonia/carbon dioxide (NH_(3)/CO_(2)-TPD) revealed that component regulation led to more oxygen vacancies and exposure of surface Co_(2)+,lower surface basicity and optimized acidity,which were beneficial for adsorption of active oxygen species and activation of methane molecules,resulting in the excellent catalytic oxidation ***,the (3.5)LC-C (3.5 is Co-to-La molar ratio) showed the optimum activity and the T50and T90(the temperature at which the CH_(4)conversion rate was 50%and 90%,respectively) were 318 and 367℃,*** theoretical calculations and in situ diffuse reflection infrared Fourier transform spectroscopy characterization,it was also found that the catalytic mechanism changes from the “Rideal-Eley” mechanism to the “Two-term” mechanism depending on the temperature windows in which the reaction takes ***,the use of the “Flynn-Wall-Ozawa” model in thermoanalytical kinetics revealed that component regulation simultaneously optimized the decomposition activation energy,further expanding the application scope of carboncontaining composites.

关键词： methane combustion Composite oxides Co3O_(4) Component regulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation,characterization and catalytic behavior of Pt-Cu nanoparticles in methane combustion

引用

Journal of Natural Gas Chemistry 2011年第5期20卷 537-542页

作者： Florica Papa Catalin Negrila Gianina Dobrescu Akane Miyazaki Ioan Balint Institute of Physical Chemistry of the Romanian Academy Spl.Independentei 202 National Institute of Material Physics Department of Chemical and Biological Sciences Faculty of Science Japan Women's University

Fine and well dispersed Pt-Cu bimetallic nanoparticles stabilized by polyvinyl pyrrolidone （PVP） were synthesized by alkaline polyol method. The molar ratio of Pt to Cu was 1 ： 1. Further, the Pt-Cu bimetallic nanoparticles were supported on alumina and their catalytic behavior in methane combustion was investigated. The as-prepared as well as the supported Pt-Cu nanoparticles were characterized by transmission elec- tron microscopy （TEM）, X-ray photoelectron spectroscopy （XPS）, fractal analysis and X-ray diffraction （XRD）. The dependence of methane combustion on the morphology and surface composition of Pt-Cu nanoparticles was analyzed based on the experimental results.

关键词： Pt-Cu bimetallic catalyst methane combustion polyol method Pt-Cu nanoparticle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Lean methane combustion over zeolite-supported Pd catalysts:Structure-performance relationship and deactivation mechanism

引用

Journal of Environmental Sciences 2024年第11期145卷 128-138页

作者： Xingyu Liu Jingkun Chen Bowen Han Renna Li Le Shi Zhongbiao Wu Xiaole Weng Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China Zhejiang Provincial Engineering Research Centre of Industrial Boiler&Furnace Flue Gas Pollution Control Hangzhou 310058China

Zeolites are a promising support for Pd catalysts in leanmethane(CH_(4))***,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in CH_(4)*** show that variations in zeolite structure and surface acidity led to distinct changes in Pd ***/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity,with activation energy(Ea)at 73 kJ/mol,while Pd/H-ZSM-5 displayed the highest turnover frequency(TOF)at 19.6×10^(−3)sec^(−1),presumably owing to its large particles with more step sites providing active sites in one particle for CH_(4)***/H-Y with dispersed PdO within pore channels and/or Pd2+ions on ion-exchange sites yielded the lowest apparent activity and ***,Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition,but introducing 3 vol.%H_(2)O caused the CH_(4)conversion rate on Pd/H-MOR drop from 100%to 63%and that on Pd/H-ZSM-5 decreased remarkably from 82%to 36%.The former was shown to originate fromzeolite structural dealumination,and the latter principally owed to Pd aggregation and the loss of active PdO.

关键词： methane combustion Pd catalysts Zeolite Structure-performance relationship Deactivation mechanism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Properties of La_(0.9)Sr_(0.1)MnO_3 and tourmaline compound catalytic materials for methane combustion

引用

Journal of Rare Earths 2014年第9期32卷 837-841页

作者：薛刚赵颖梁金生苑砚坤王赛飞陈丹 Institute of Power Source and Ecomaterials Science School of Materials Science and Engineering Hebei University of Technology

A novel catalytic material Lao.9Sr0.1MnO3 and tourmaline compound catalytic material was synthesized in the base of traditional catalytic material La0.9Sr0.1MnO3 which exhibited excellent catalytic activity for methane combustion. Different contents of toumaaline were added to give a series ofLa0.9Sr0.1MnO3 and tourmaline catalytic material through a sol-gel method. Samples above were characterized and analyzed by means of X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Brunauer-Emmett-Teller method （BET）, temperaalre programmed reduction （TPR）, catalytic activity test and contact angle test. The as-prepared sample with 2% （m/m） tourmaline showed good homogeneity surface morphology and displayed the optimal catalytic activity. The light-off temperature reduced by 10 ℃ and the T90 decreased by 15 ℃. In addition, the mechanism of the reinforcement of catalytic activity was explored.

关键词： methane combustion perovskite tourmaline sol-gel method catalytic rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Synthesis of La-hexaaluminate catalyst for methane combustion by a reverse SDS microemulsion

引用

Rare Metals 2011年第4期30卷 337-342页

作者： YU Ying WANG Liangshi CUI Meisheng SHI Yongxi LUO Ruixian CHEN Aifan National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals and Grirem Advanced Materials Co. Ltd. Beijing100088 China Science College Beo＇ing University of Chemical Technology Beijing 100029 China

La-hexaaluminate catalyst for methane catalytic combustion was synthesized by a reverse microemulsion. Pseudo-temary phase diagrams of a quaternary microemulsion system of sodium dodecyl sulfate （SDS）, n-pentanol, n-octane, and water （or Al（NO3）3 solution） were presented. The effects of alcohol chain length, cosurfactant-to-surfaqtant rat!0, and salt concentration on the formation and stability of the microemul- sion system were studied. The phenomenon that the conductivity changed with water supported the phase behavior of the microemulsion system. La（MnffFex）Al12_xO19_a catalysts, applied in methane combustion and with high-temperature stability, were synthesized within the stable areas of the phase diagram of the microemulsion system, when SDS was chosen as surfactant, n-pentanol as cosurfactant, and n-octane as oil phase. The physical properties and structure of the catalysts were characterized by BET method, transmission electron microscope （TEM）, and X-ray diffraction （XRD）. A micro-fixed-bed reactor was used to measure the catalytic activity of hexaaluminates in methane combustion. The results show that the reverse microemulsions can be used to produce discrete La-hexaaluminate nanoparticles that display excellent methane combustion activity owing to their high surface area and high thermal stability.

关键词： catalysts methane combustion phase diagrams microemulsions hexaaluirtinates lanthanum compounds

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation of LaFe_(0.95)Pd_(0.05)O_3 perovskites and their catalytic performances in methane combustion

引用

Journal of Natural Gas Chemistry 2012年第2期21卷 113-118页

作者： Xiaojing Zhang Yong Li Huaju Li Wenjie Shen State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

The physic-chemical properties of LaFe0.95Pd0.05O3 perovskites were strongly dependent on the temperature of calcination. Most of the organic substances and inorganic impurities were readily removed at 723 K but single-phase and well crystallized perovskite structure was formed at 873 K. With further raising the calcination temperature, the crystallite size of LaFe0.95Pd0.05O3 increased considerably. The LaFe0.95Pd0.05O3 sample that calcined at 1073 K showed only comparable activity as the reference LaFeO3 catalyst, in particular below 923 K, but pre-treatment with the reaction gas at 1223 K resulted in significantly enhanced activity due to the generation of active PdO species on the surface. The hysteresis feature upon heating-cooling cycle further confirmed the strong interaction between Pd and LaFeO3 in the perovskite structure.

关键词： perovskite LaFe0.95Pd0.05O3 calcination temperature pre-treatment methane combustion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Catalytic performance for methane combustion of supported Mn-Ce mixed oxides

引用

Journal of Rare Earths 2008年第6期26卷 836-840页

作者：士丽敏储伟瞿芬芬胡金燕李民敏 School of Chemical Engineering Sichuan University Department of Environment Sichuan University

A series of supported Mn-Ce mixed oxide catalysts were prepared by the impregnation method and used for the oxidation of methane. The catalysts were characterized by N2 adsorption （BET）, X-ray diffraction （XRD）, laser Raman spectrum （LRS）, and temperature programmed reduction （TPR） techniques. The XRD and LRS results confirmed the high dispersion of active components or formation of solid solution between manganese and cerium oxides in the bulk and on the surface of mixed oxide catalysts. The reducibility was remarkably promoted by the stronger synergistic interaction between the two oxides from H2-TPR measurements. As expected, all the experimental mixed oxide catalysts showed excellent activity for methane combustion at low temperature. Especially, for the catalyst with Mn-Ce ratio 3：7, methane conversion reached 92% at a temperature as low as 470 ℃.

关键词： Mn-Ce mixed oxides solid solution methane combustion rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Surfactant-aided hydrothermal preparation of La(2-x)Sr_xCuO_4 single crystallites and their catalytic performance on methane combustion

引用

Journal of Natural Gas Chemistry 2012年第1期21卷 69-75页

作者： Lei Zhang Yue Zhang Jiguang Deng Hongxing Dai Laboratory of Catalysis Chemistry and Nanoscience Department of Chemistry and Chemical EngineeringCollege of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

Perovskite-like oxide La2-xSrxCuO4 （x = 0, 1） single crystallites with microrod-like morphologies and tetragonal crystal structures were prepared hydrothermally at 240 ℃ with poly（ethylene glycol）（PEG） or hexadecyltrimethyl ammonium bromide （CTAB） as a surfactant and after calcination at 850 ℃. The physicochemical properties of the materials were characterized by means of XRD, BET, SEM, TEM/SAED （selected-area electron diffraction）, XPS and H2-TPR techniques. It is found that doping Sr2＋ to La2CuO4 lattice enhanced the catalytic activity for methane combustion and the LaSrCuO4 catalyst derived from PEG is the best among the tested ones. It is concluded that factors, such as adsorbed oxygen species concentration, reducibility and surface area, determined the catalytic performance of such single-crystalline materials.

关键词： perovskite-like oxide La2-xSrzCuO4 single crystallite surfactant-aided hydrothermal preparation methane combustion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：