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CO_2 selective hydrogenation to synthetic natural gas(SNG) over four nano-sized Ni/ZrO_2 samples:ZrO_2 crystalline phase & treatment impact

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Journal of Energy Chemistry 2016年第6期25卷 1070-1077页

作者： Min Chen Zhanglong Guo Jian Zheng Fangli Jing Wei Chu School of Chemical Engineering Sichuan University Institute of New Energy and Low-Carbon Technology Sichuan University Institute for Integrated Catalysis Pacific Northwest National Laboratory

Two type zirconia (monoclinic and tetragonal phase ZrO2) carriers were synthesized via hydrothermal route, and nano-sized zirconia supported nickel catalysts were prepared by incipient impregnation then followed thermal treatment at 300?°C to 500?°C, for the CO2selective hydrogenation to synthetic natural gas (SNG). The catalysts were characterized by XRD, CO2-TPD-MS, XPS, TPSR (CH4, CO2) techniques. For comparison, the catalyst NZ-W-400 (monoclinic) synthesized in water solvent exhibited a better catalytic activity than the catalyst NZ-M-400 (tetragonal) prepared in methanol solvent. The catalyst NZ-W-400 displayed more H2absorbed sites, more basic sites and a lower temperature of initial CO2activation. Then, the thermal treatment of monoclinic ZrO2supported nickel precursor was manufactured at three temperature of 350, 400, 500?°C. The TPSR experiments displayed that there were the lower temperature for CO2activation and initial conversion (185?°C) as well as the lower peak temperature of CH4generation (318?°C), for the catalyst calcined at 500?°C. This sample contained the more basic sites and the higher catalytic activity, evidenced byCO2-TPD-MS and performance measurement. As for the NZ-W-350 sample, which exhibited the less basic sites and the lower catalytic activity, its initial temperature for CO2activation and conversion was higher (214?°C) as well as the higher peak temperature of CH4formation (382?°C). ? 2016 Science Press

关键词： Carbon dioxide catalyst activity catalysts Chemical activation Heat treatment Hydrogenation Natural gas Nickel Organic solvents Zirconia Zirconium alloys

Comparative characterization of iridium loading on catalyst assessment under different conditions

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International Journal of Minerals,Metallurgy and Materials 2021年第7期28卷 1233-1239页

作者： Zahra Amirsardari Akram Dourani Mohamad Ali Amirifar Nooredin Ghadiri Massoom Space Transportation Research Institute Iranian Space Research CenterTehranIran

To discuss the potential role of iridium(Ir)nanoparticles loaded under atmospheric and high pressures,we prepared a series of cata-lysts with the same active phase but different contents of 10wt%,20wt%,and 30wt%on gamma-alumina for decomposition of hydrazine.Un-der atmospheric pressure,the performance of the catalyst was better when 30wt%of the Ir nanoparticles was used with chelating agent that had greater selectivity of approximately 27%.The increase in the reaction rate from 175 to 220 h^(−1)at higher Ir loading(30wt%)was due to a good dispersion of high-number active phases rather than an agglomeration surface.As a satisfactory result of this investigation at high pressure,Ir catalysts with different weight percentages showed the same stability against crushing and activity with a characteristic velocity of approxim-ately 1300 m/s.

关键词： iridium nanoparticles catalyst activity laboratory reactor atmospheric pressure high pressure

Catalytic performances of Ni/mesoporous SiO_2 catalysts for dry reforming of methane to hydrogen

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Journal of Energy Chemistry 2016年第4期25卷 709-719页

作者： Fei Huang Rui Wang Chao Yang Hafedh Driss Wei Chu Hui Zhang College of Chemistry and Chemical Engineering Southwest Petroleum University Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province Drilling & Production Engineering Technology Research Institute CNPC Chuanqing Drilling Engineering Co.Ltd. SABIC Chair in Catalysis King Abudulaziz University Department of Chemical Engineering Sichuan University

Several mesoporous silicas with different morphologies were controllably prepared by sol-gel method with adjustable ratio of dual template, and they were further impregnated with aqueous solution of nickel nitrate, followed by calcination in air. The synthesized silica supports and supported nickel samples were characterized using N2-adsorption/desorption, X-ray diffraction (XRD), H2temperature-programmed reduction (H2-TPR), Scanning electron microscope (SEM), Transmission electron microscope (TEM) and thermo-gravimetric analysis (TGA-DTG) techniques. The Ni nanoparticles supported on shell-like silica are highly dispersed and yielded much narrower nickel particle-size than those on other mesoporous silica. The methane reforming with dioxide carbon reaction results showed that Ni nanoparticles supported on shell-like silica carrier exhibited the better catalytic performance and catalytic stability than those of nickel catalyst supported on other silica carrier. The thermo-gravimetric analysis on used nickel catalysts uncovered that catalyst deactivation depends on the type and nature of the coke deposited. The heterogeneous nature of the deposited coke was observed on nickel nanoparticles supported on spherical and peanut-like silica. Much narrower and lower TGA derivative peak was founded on Ni catalyst supported on the shell-like silica. ? 2016 Science Press

关键词： Carbon catalyst activity catalyst deactivation catalysts Catalytic reforming Coke Gravimetric analysis Hydrogen Methane Nanoparticles Nickel Particle size Scanning electron microscopy Silica Sol gel process Sol gels Solutions Thermogravimetric analysis Transmission electron microscopy X ray diffraction

Highly efficient and stable electrooxidation of methanol and ethanol on 3D Pt catalyst by thermal decomposition of In2O3 nanoshells

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Journal of Energy Chemistry 2017年第1期26卷 193-199页

作者： Yuhang Xie Hulin Zhang Guang Yao Saeed Ahmed Khan Xiaojing Cui Min Gao Yuan Lin State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina Center for Information in Medicine University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina The First Sub-Institute Nuclear Power Institute of ChinaChengdu 610041SichuanChina

In this paper In2O3nanoshells have been synthesized via a facile hydrothermal approach. The nanoshells can be completely cracked into pony-size nanocubes by annealing, which are then used as a support of Pt catalyst for methanol and ethanol electrocatalytic oxidation. The prepared In2O3and supported Pt catalysts (Pt/In2O3) were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), field effect scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry and electrochemical impedance spectroscopy (EIS) were carried out, indicating the excellent catalytic performance for alcohol electrooxidation can be achieved on Pt/In2O3nanocatalysts due to the multiple active sites, high conductivity and a mass of microchannels and micropores for reactant diffusions arising from 3D frame structures compared with that on the Pt/C catalysts. ? 2016 Science Press

关键词： Alcohols catalyst activity catalysts Chronoamperometry Cyclic voltammetry Decomposition Electrocatalysis Electrochemical impedance spectroscopy Electron microscopy Electrooxidation Energy dispersive spectroscopy Ethanol High resolution transmission electron microscopy Methanol Nanoshells Nanostructured materials Nanostructures Platinum Scanning electron microscopy Transmission electron microscopy X ray diffraction X ray photoelectron spectroscopy X ray spectroscopy

Effects of the crystallization time on the mesoporous structure,texture, morphology and styrene oxidation performances of V-MCM-41

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Journal of Energy Chemistry 2016年第6期25卷 1058-1063页

作者： Junqiang Xu Qiang Zhang Fang Guo Jingping Hong Wei Chu College of Chemistry & Chemical Engineering Chongqing University of Technology College of Chemistry and Materials Science South Central University for Nationalities Department of Chemical Engineering Sichuan University

The new V-MCM-41 molecular sieves with good ordered hexagonal mesoporous structure and crystallinity were synthesized through in-situ hydrothermal preparation method. The effects of the crystallization time were discussed. The synthesized samples were characterized by X-ray diffraction, N2adsorption/desorption, Fourier transformed infrared and scanning electron microscopy. The different structures, textures, morphologies of V-MCM-41 obtained with different crystallization times were observed and analyzed on the basis of the characterized results. The results showed that the V-MCM-41 molecular sieve obtained at 110?°C for 48?h crystallization times was of good spherical morphology, ordered hexagonal structure, most uniform pore size distribution and high surface area compared with other samples. Meanwhile, the V-MCM-41 molecular sieve with the high skeleton Si condensation and the good crystallinity was obtained. The heteroatom could be incorporated into MCM-41 framework with increasing crystallization times, which was beneficial to improve the catalytic activity and selectivity of pure siliceous MCM-41. The V-MCM-41 showed the good catalytic selectivity in catalytic oxidation of styrene using hydrogen peroxide, and the selectivity of the benzaldehyde and phenylacetic acid reached 30.68% and 49.44%, respectively. ? 2016

关键词： catalyst activity Molecular sieves Morphology Pore size Scanning electron microscopy Sieves Styrene X ray diffraction

Nanocarbons and their hybrids as catalysts for non-aqueous lithium–oxygen batteries

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Journal of Energy Chemistry 2016年第6期25卷 957-966页

作者： Yunchuan Tu Dehui Deng Xinhe Bao State Key Laboratory of Catalysis iChEM Dalian Institute of Chemical Physics Chinese Academy of Sciences Collaborative Innovation Center of Chemistry for Energy Materials College of Chemistry and Chemical Engineering Xiamen University University of Chinese Academy of Sciences

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

关键词： Carbon nanofibers catalyst activity catalysts Electric batteries Electrocatalysis Electrocatalysts Electrodes Electrolytic reduction Lithium Lithium batteries Oxygen Secondary batteries Yarn

Improved Performance of W/HZSM-5 catalysts for Dehydroaromatization of Methane

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Journal of Natural Gas Chemistry 2004年第3期13卷 148-159页

作者： Nor Aishah Saidina Amin Kusmiyati Department of Chemical Engineering Faculty of Chemical and Natural Resources EngineeringUniversiti Teknologi Malaysia 81310 UTM Skudai Johor Malaysia.Department of Chemical Engineering Faculty of Chemical and Natural Resources EngineeringUniversiti Teknologi Malaysia 81310 UTM Skudai Johor Malaysia.

The dehydroaramatization of methane over W-supported ZSM-5 with varying degrees of Li+ ion-exchanged catalysts was studied with and without oxygen at 1073 K and atmospheric pressure. catalyst activity and stability were found to be influenced by the catalyst acidity related to Bronsted acid sites and by the presence of oxygen in the feed. The NH3-TPD and FTIR-pyridine results demonstrated that partially exchanged of H+ ions by Li+ into the W/HZSM-5 catalysts could be used to control the amount of strong acid sites on the catalyst surface. Without oxygen, the 3WHLi-Z (5:1) catalyst that has strong acid sites equal to nearly 74% of the original strong acid sites in the parent HZSM-5 exhibited the highest methane conversion and selectivity towards aromatics. However, the catalyst deactivated in a five hour period. In the presence of oxygen, the catalyst activity and stability could be improved further. The results of this study revealed that a suitable amount of strong Bronsted acid sites as well as oxygen addition in the feed increased the catalyst activity and stability. The 3WHLi-Z(5:1) catalyst exhibited improved performance in the dehydroaromatization of methane.

关键词： dehydroaromatization methane W-supported ZSM-5 partial ion exchange H+ ion Li ion catalyst activity catalyst stability catalyst acidity oxygen presence improved performance

Regeneration of Spent catalyst and Impregnation of catalyst by Supercritical Fluid

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International Journal of Analytical Mass Spectrometry and Chromatography 2016年第4期4卷 51-65页

作者： Farid M. Gumerov Bernard Le Neindre Timur R. Bilalov Ajrat A. Sagdeev Federal State Budgetary Educational Institution of Higher Professional Education “Kazan National Research Technological University” Kazan Russia Université Paris 13 Sorbonne Paris Cité Laboratoire des Sciences des Procédés et des Matériaux CNRS (UPR 3407) F-93430 Villetaneuse France Federal State Educational Institution of Higher Professional Education Nizhnekamsk Chemical Technology Institute Nizhnekamsk Russia

The possibility and feasibility of using supercritical fluid СО2 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 СО2 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-CO2 extraction process has been conducted. The possibility of using supercritical fluid CO2 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 CO2 impregnation process condition has been implemented. A comparison of the characteristics of palladium catalyst samples synthesized using the conventional approach and SC-CO2 impregnation process has been conducted and presented in the book.

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